U.S. patent application number 10/756712 was filed with the patent office on 2004-09-23 for catheter and introducer needle assembly with needle shield.
Invention is credited to Brimhall, Greg L., Cindrich, Christopher N., Harding, Weston F., Howell, Glade H..
Application Number | 20040186434 10/756712 |
Document ID | / |
Family ID | 32398362 |
Filed Date | 2004-09-23 |
United States Patent
Application |
20040186434 |
Kind Code |
A1 |
Harding, Weston F. ; et
al. |
September 23, 2004 |
Catheter and introducer needle assembly with needle shield
Abstract
A catheter and introducer needle assembly with a needle shield
is provided. The needle shield includes a means for preventing
unwanted distal movement of the needle once the needle has been
withdrawn into the needle shield. The needle shield also includes a
means for connecting the needle shield to the catheter hub until
the sharp distal tip of the introducer needle has been withdrawn
into the needle shield. Thus, when the distal end of the introducer
needle extends from the distal portion of the needle shield, the
needle shield is connected to the catheter hub and when the sharp
distal end of the introducer needle is withdrawn into the needle
shield, the needle shield is disconnected from the catheter hub. At
that point, the sharp needle tip is secured within the needle
shield.
Inventors: |
Harding, Weston F.; (Lehi,
UT) ; Cindrich, Christopher N.; (Draper, UT) ;
Howell, Glade H.; (Sandy, UT) ; Brimhall, Greg
L.; (W. Jordan, UT) |
Correspondence
Address: |
DAVID W. HIGHET, VP AND CHIEF IP COUNSEL
BECTON, DICKINSON AND COMPANY
1 BECTON DRIVE, MC 110
FRANKLIN LAKES
NJ
07417-1880
US
|
Family ID: |
32398362 |
Appl. No.: |
10/756712 |
Filed: |
January 13, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10756712 |
Jan 13, 2004 |
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09717148 |
Nov 21, 2000 |
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6749588 |
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09717148 |
Nov 21, 2000 |
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09590600 |
Jun 9, 2000 |
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09590600 |
Jun 9, 2000 |
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09312335 |
May 14, 1999 |
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6379333 |
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09312335 |
May 14, 1999 |
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09057718 |
Apr 9, 1998 |
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6004294 |
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09717148 |
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09499331 |
Feb 4, 2000 |
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09499331 |
Feb 4, 2000 |
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09312335 |
May 14, 1999 |
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6379333 |
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09312335 |
May 14, 1999 |
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09057718 |
Apr 9, 1998 |
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6004294 |
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09717148 |
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09406026 |
Sep 24, 1999 |
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Current U.S.
Class: |
604/164.08 |
Current CPC
Class: |
A61M 2005/325 20130101;
A61M 25/0625 20130101; A61M 5/3273 20130101; A61M 2005/3247
20130101; A61M 5/3275 20130101 |
Class at
Publication: |
604/164.08 |
International
Class: |
A61M 005/178 |
Claims
We claim:
1. A catheter and introducer needle assembly, comprising: a
catheter having a proximal end and a distal end; a catheter hub in
fluid communication with the catheter and having a proximal end and
a distal end connected to the proximal end of the catheter; an
extension tube attached to the catheter hub and in fluid
communication with the catheter hub; an introducer needle removably
disposed in the catheter and having a proximal end and a distal
end, the introducer needle including a main portion and an enlarged
diameter portion; a needle shield selectively engaged to the
catheter hub and slidingly mounted to the introducer needle for
movement from a first position to a second position at the distal
end of the introducer needle, the needle shield including: a
housing having a proximal portion and a distal portion and a
cavity, wherein the needle is disposed, at least in part, within
the cavity; a wall formed in the housing; at least one tab disposed
within the cavity and disposed adjacent to the wall and proximal to
the wall; and means for preventing unwanted distal movement of the
needle shield off the distal end of the introducer needle; wherein,
when the needle shield is moved from the first position to the
second position, the tab flexes proximally to permit passage of the
enlarged diameter portion of the introducer needle; and wherein,
when the needle shield is in the second position, the tab is
prevented from flexing distally by the wall.
2. The catheter and introducer needle assembly of claim 1 further
comprising a resilient clip mounted in the needle shield which is
adapted to flex into and out of engagement with the catheter hub
wherein, when the needle shield is in the first position, the
introducer needle contacts the clip so it is flexed into a biased
position into engagement with the catheter hub and, when the needle
shield is in the second position, the introducer needle disengages
the clip so it can flex to its unbiased position out of engagement
with the catheter hub.
3. The catheter and introducer needle assembly of claim 1 further
comprising a retention plate disposed in the housing of the needle
shield, wherein at least two tabs are leaf springs connected to the
retention plate.
4. The catheter and introducer needle assembly of claim 1 wherein
the wall and the tab are substantially perpendicular to an axis of
the catheter and introducer needle assembly and wherein the tab is
in contact with the wall.
5. The catheter and introducer needle assembly of claim 4 wherein
the tab defines a hole that has a radius which is smaller than the
radius of the enlarged diameter portion.
6. The catheter and introducer needle assembly of claim 5 wherein
the tab defines a hole that is larger than the main portion of the
introducer needle and the wall includes an opening which is larger
than the enlarged diameter portion of the introducer needle.
7. The catheter and introducer needle assembly of claim 1 wherein
the means for preventing unwanted distal movement of the needle
shield off the distal end of the introducer needle includes a
tether.
8. The catheter and introducer needle assembly of claim 1 wherein
the means for preventing unwanted distal movement of the needle
shield off the distal end of the introducer needle includes an
opening in the housing that is smaller than the enlarged diameter
portion of the introducer needle.
9. The catheter and introducer needle assembly of claim 1 wherein
the means for preventing unwanted distal movement of the needle
shield off the distal end of the introducer needle includes a
washer in the housing disposed about the introducer needle and
including a hole that is smaller than the enlarged diameter portion
of the introducer needle.
10. A catheter and introducer needle assembly, comprising: a
catheter having a proximal end and a distal end; a catheter hub in
fluid communication with the catheter and having a proximal end and
a distal end connected to the proximal end of the catheter; an
introducer needle removably disposed in the catheter and having a
proximal end and a distal end, the introducer needle including a
main portion and a discontinuous portion disposed near the distal
end; a needle shield selectively engaged to the catheter hub and
slidingly mounted to the introducer needle for movement from a
first position to a second position at the distal end of the
introducer needle, the needle shield including: a housing having a
proximal portion, a distal portion, an axis extending from the
proximal portion to the distal portion, and a cavity, wherein the
needle is slidingly disposed, at least in part, within the cavity;
a medial wall formed in the housing and being disposed
perpendicular to the axis of the housing; flexible tabs disposed
adjacent to and in contact with the medial wall; wherein, when the
needle shield is in the first position, the introducer needle is
disposed between the tabs, and the tabs are adapted to permit
passage of the main portion of the introducer needle; wherein, when
the needle shield is moved from the first position to the second
position, the tabs permit passage of the discontinuous portion of
the introducer needle; and wherein, when the needle shield is in
the second position, the tabs engage the discontinuous portion of
the needle introducer needle to prevent relative movement between
the needle shied and the introducer needle in at least one
direction.
11. The catheter and introducer needle assembly of claim 10 further
comprising a resilient clip that is adapted to flex between a
biased position and an unbiased position in a plane substantially
perpendicular to the axis of the housing wherein, in the biased
position, the clip engages the catheter hub and, in the unbiased
condition, the clip disengages the catheter hub and wherein, when
the needle shield is in the first position, the clip is held to one
side of the introducer needle so it is flexed into the biased
position and, when the needle shield is in the second position, the
clip flexes to the unbiased position out of engagement with the
catheter hub.
12. A needle shielding assembly comprising: a needle having a
proximal end, a distal end, an axis, a main portion, a
discontinuous portion and a sharp tip at the distal end; and a
needle shield slidingly mounted to the introducer needle for
movement from a first position to a second position covering the
sharp tip of the introducer needle, the needle shield including: a
housing having a proximal portion and a distal portion and a
cavity, wherein the needle is disposed, at least in part, within
the cavity; a wall formed in the housing; at least one flexible tab
disposed adjacent to the wall and proximal to the wall; and means
for preventing unwanted distal movement of the needle shield off
the sharp tip of the needle when the shield is in the second
position; wherein, when the needle shield is moved from the first
position to the second position, the tab permits passage of the
discontinuous portion of the needle; and wherein, when the needle
shield is in the second position, the tab restrains the
discontinuous portion and is prevented from flexing distally by the
wall.
13. The needle shielding assembly of claim 12 further comprising a
catheter having a catheter hub, wherein the catheter is slidingly
engaged with the needle, and further comprising a clip connected to
the housing and selectively engaged to the catheter hub.
14. The needle shielding assembly of claim 13 wherein, when the
needle shield is in the first position, the clip is held to one
side of the needle in a biased position and, when the needle shield
is in the second position, the clip flexes out of engagement with
the catheter hub.
15. The needle shielding assembly of claim 13 wherein the clip has
a generally V-shaped configuration including a pair of legs.
16. The needle shielding assembly of claim 12 wherein the
discontinuous portion has a tapered proximal portion and a distally
facing shoulder.
17. The needle shielding assembly of claim 12 wherein the
discontinuous portion is a crimp or a notch.
18. The needle shielding assembly of claim 12 wherein the flexible
tab defines a through hole sized to permit passage of the main
portion of the needle but to engage the discontinuous portion as it
passes through the tabs.
19. The needle shield assembly of claim 12 wherein the tab is
disposed substantially perpendicular to the axis of the needle.
20. A needle for use with a needle shield assembly comprising: a
hollow needle cannula having a proximal end and a distal end and an
axis extending from the proximal end to the distal end; a sharp tip
formed at the distal end; a hub engaged to the proximal end of the
needle; a discontinuity permanently located on the needle near the
distal end of the needle, wherein the discontinuity comprises, at
least in part, an enlarged diameter portion; wherein the enlarged
diameter portion includes a tapered proximal portion and a distally
facing shoulder; and wherein the distally facing shoulder is
substantially perpendicular to the axis of the hollow needle
cannula.
21. The needle of claim 20 further comprising a notch disposed in
the hollow needle cannula, wherein the notch is positioned along
the hollow needle cannula at a point proximal to the
discontinuity.
22. A needle shield for use with the needle of claim 20 comprising
a housing slidingly mounted on the needle cannula and a means for
engaging the discontinuity to secure it in relation to the
housing.
23. A catheter and introducer needle assembly, comprising: a
catheter having a proximal end and a distal end; a catheter hub in
fluid communication with the catheter and having a proximal end and
a distal end connected to the proximal end of the catheter; an
introducer needle slidingly disposed in the catheter and having a
proximal end and a distal end, the introducer needle including a
main portion and at least one shoulder extending circumferentially
about the needle; a needle shield selectively engaged to the
catheter hub and slidingly moveable with respect to the introducer
needle from a first position to a second position at the distal end
of the introducer needle, the needle shield comprising: a housing
having an open proximal portion, a distal portion, an axis
extending from the proximal portion to the distal portion, and a
cavity, wherein the needle is slidingly disposed, at least in part,
within the cavity; at least one resilient tab extending radially
inward in the housing; wherein, when the needle shield is in the
first position, it is engaged to the catheter hub and the
introducer needle is disposed in contact with the tab, and the tab
is adapted to permit passage of the main portion of the introducer
needle; wherein, when the needle shield is moved from the first
position to the second position, the tab permits passage of the
main portion of the introducer needle; and wherein, when the needle
shield is in the second position, the tab engages the shoulder of
the needle introducer needle to prevent relative movement between
the needle shied and the introducer needle in at least one
direction.
24. The catheter and introducer needle assembly of claim 23 wherein
the shoulder extends completely circumferentially about the
needle.
25. The catheter and introducer needle assembly of claim 23 wherein
the shoulder has an inner diameter less than the outer diameter of
the main portion of the needle.
26. The catheter and introducer needle assembly of claim 23 wherein
the shoulder has an outer diameter greater than the outer diameter
of the main portion of the needle.
Description
[0001] This application is a continuation of application Ser. No.
09/717,148 filed on Nov. 21, 2000, which is a continuation-in-part
of application Ser. No. 09/590,600 filed Jun. 9, 2000, which is a
continuation-in-part of application Ser. No. 09/312,335 filed May
14, 1999, which is a continuation-in-part of application Ser. No.
09/057,718 filed Apr. 9, 1998, now U.S. Pat. No. 6,004,294.
Application Ser. No. 09/717,148 is also a continuation-in-part of
application Ser. No. 09/499,331 filed Feb. 4, 2000, which is a
continuation-in-part of application Ser. No. 09/312,335 filed May
14, 1999, which is a continuation-in-part of application Ser. No.
09/057,718 filed Apr. 9, 1998, now U.S. Pat. No. 6,004,294.
Application Ser. No. 09/717,148 is also a continuation-in-part of
application Ser. No. 09/406,026 filed Sep. 24, 1999.
BACKGROUND OF THE INVENTION
[0002] The subject invention relates to a catheter and introducer
needle assembly that includes a needle shield that will safely
shield the sharp distal tip of the introducer needle after the
needle has been used to insert the catheter into a patient. In
addition, this invention includes a mechanism to connect the needle
shield to the catheter until the sharp distal tip of the introducer
needle is covered by the needle shield.
[0003] Catheters, particularly intravascular (IV) catheters, are
used for infusing fluid, such as normal saline solution, various
medicaments and total parenteral nutrition, into a patient,
withdrawing blood from a patient or monitoring various parameters
of the patient's vascular system. Peripheral IV catheters tend to
be relatively short, and typically are on the order of about two
inches or less in length. The most common type of IV catheter is an
over-the-needle peripheral IV catheter. As its name implies, an
over-the-needle catheter is mounted over an introducer needle
having a sharp distal tip. At least the distal portion of the
catheter tightly engages the outer surface of the needle to prevent
peelback of the catheter and thus facilitates insertion of the
catheter into the blood vessel. The catheter and the introducer
needle are assembled so that the distal tip of the introducer
needle extends beyond the distal tip of the catheter with the bevel
of the needle facing up away from the patient's skin.
[0004] The catheter and introducer needle assembly is inserted at a
shallow angle through the patient's skin into a blood vessel. There
are many techniques for inserting such a catheter and introducer
needle assembly into a patient. In one insertion technique, the
introducer needle and catheter are inserted completely into the
blood vessel together. In another technique, the introducer needle
is partially withdrawn into the catheter after the initial
insertion into the blood vessel. The catheter is then threaded over
the needle and inserted completely into the blood vessel.
[0005] In order to verify proper placement of the catheter in the
blood vessel, the clinician confirms that there is flashback of
blood in a flashback chamber. The flashback chamber is typically
formed as part of the needle hub. Once proper placement of the
catheter into the blood vessel is confirmed, the clinician applies
pressure to the blood vessel by pressing down on the patient's skin
over the blood vessel distal of the introducer needle and the
catheter. This finger pressure occludes or at least minimizes
further blood flow through the introducer needle and the catheter.
The clinician then withdraws the introducer needle, leaving the
catheter in place, and attaches an appropriate device to the
catheter. Such a device can include a fluid delivery device, a PRN,
a deadender cap or a blood pressure monitoring probe. Once the
introducer needle is withdrawn from the catheter, the introducer
needle is a "blood contaminated sharp" and must be properly
handled.
[0006] In recent years, there has been great concern over the
contamination of clinicians with a patient's blood and a
recognition that "blood contaminated sharps" must be disposed to
avoid an accidental needle stick. This concern has arisen because
of the advent of currently incurable and fatal diseases, such as
Acquired Immunosuppressive Deficiency Syndrome ("AIDS"), which can
be transmitted by the exchange of body fluids from an infected
person to another person. Thus, contact with the body fluid of an
AIDS infected person must be avoided. As noted above, if an
introducer needle has been used to place a catheter in a blood
vessel of an AIDS infected person, the introducer needle, via its
sharp distal tip, is a vehicle for the transmission of the disease.
Although clinicians are aware of the need to properly handle "blood
contaminated sharps", unfortunately in certain medical
environments, such as emergency situations or as a result of
inattention or neglect, needlesticks with a contaminated introducer
needle still occur.
[0007] As a result of the problem of accidental needlesticks by
"blood contaminated sharps", various needle shields have been
developed. Generally, such needle shields work for their intended
purpose but could be improved. For example, some needle shields are
bulky, difficult to use, require special features or techniques to
be operative, or may leave the sharp distal tip exposed after use
until the clinician manually activates the needle shielding
mechanism.
[0008] In addition, some of these needle shields can be easily
disconnected from the catheter hub before the needle shield covers
the sharp distal tip of the introducer needle. A mechanism to avoid
this premature disconnection is a plurality of fingers
longitudinally extending from the needle shield with tabs extending
radially inwardly from the fingers that engage the flange at the
proximal end of the catheter hub. The fingers and tabs hold the
needle shield to the catheter. The configuration of the fingers and
tabs is designed such that the force needed to overcome the
engagement between the fingers and tabs and the catheter hub is
greater than the typical force needed to move the introducer needle
proximally into the needle shield. However, once the introducer
needle has been fully withdrawn into the needle shield, the
clinician can exert a greater proximally directed force to remove
the needle shield from the catheter hub. Thus the needle shield
remains engaged with the catheter until the introducer needle has
been completely removed from the catheter and is safely shielded in
the needle shield. Unfortunately, this configuration does not
consistently ensure that the needle shield remains connected to the
catheter hub until the introducer needle is locked in the needle
shield. This may be undesirable because the contaminated needle
could then be exposed increasing the chances for an accidental
needlestick.
SUMMARY OF THE INVENTION
[0009] It is therefore an object of this invention to provide a
needle shield that is compact.
[0010] It is another object of this invention to provide a needle
shield that is simple and easy to use.
[0011] It is still another object of this invention to provide a
needle shield that requires no special features or techniques to be
operative.
[0012] It is yet another object of this invention to provide a
needle shield that automatically shields the sharp distal tip of
the introducer needle upon withdrawal of the introducer needle from
the catheter.
[0013] It is a further object of this invention to provide a
catheter and introducer needle assembly with a needle shield where
the needle shield remains connected to the catheter until the
needle shield covers the sharp distal tip of the introducer
needle.
[0014] The catheter and introducer needle assembly with needle
shield of this invention includes a catheter, an introducer needle
and a needle shield.
[0015] The catheter has a distal end and a proximal end connected
to the distal end of a catheter hub. The catheter is coaxially
disposed over the introducer needle and the distal portion of the
catheter tightly engages the outer surface of the introducer needle
to prevent peelback of the catheter and thus facilitates insertion
of the catheter into the patient's blood vessel. Prior to use, the
catheter is located about the introducer needle so that the sharp
distal tip of the introducer needle is distal of the distal end of
the catheter.
[0016] The introducer needle has a sharp distal tip and a proximal
end connected to the distal end of a needle hub. A flashback
chamber may be defined in the needle hub. Typically a vented plug
is located in the open proximal end of the flashback chamber to
allow air to escape from the flashback chamber when blood enters
the flashback chamber from the introducer needle. The introducer
needle may also define, along a distal portion thereof, a
discontinuous portion, which can take a number of different forms.
For example, a slot, or an enlarged diameter portion formed on the
introducer needle may be used. If an enlarged diameter portion is
used it may have a tapered proximal portion or a tapered distal
portion or both. The taper can be oriented at almost any angle to
the longitudinal axis of the introducer needle. In certain
embodiments, the distal portion may be oriented generally
perpendicular to the longitudinal axis of the introducer needle.
However, the main requirement is that the discontinuous portion has
any configuration that cooperates with a lock associated with the
needle shield to prevent unwanted distal movement of the introducer
needle with respect to the needle shield. In other words, the sharp
distal tip will not be re-exposed from the distal end of the needle
shield once the sharp distal tip has been withdrawn into the needle
shield after use. The discontinuous portion may also cooperate with
a means for preventing unwanted proximal movement of the introducer
needle with respect to the needle shield once the sharp distal tip
of the introducer needle has been proximally withdrawn into the
needle shield. This prevents re-exposure of the sharp distal tip of
the introducer needle from the proximal end of the needle
shield.
[0017] The needle shield is defined by a housing having an internal
cavity through which the introducer needle extends. A lock
associated with the needle shield prevents unwanted distal movement
of the introducer needle once the introducer needle has been
proximally withdrawn into the needle shield. Also associated with
the needle shield is a means for preventing unwanted proximal
movement of the introducer needle once the sharp distal tip of the
introducer needle has been proximally withdrawn into the needle
shield.
[0018] Various locks can be used to prevent unwanted distal
movement of the sharp distal tip of the introducer needle out of
the needle shield once the sharp distal tip has been proximally
withdrawn into the introducer needle shield. For example, a
transverse barrier that rides along the needle shaft as the
introducer needle is withdrawn into the needle shield and that
moves in front of the sharp distal tip once the needle tip is
proximal of the transverse barrier may be used. In such an
embodiment, no discontinuous portion is needed on the introducer
needle. Alternatively, a lock may be used in conjunction with a
discontinuous portion formed on the introducer needle. In such an
embodiment, the lock allows the discontinuous portion of the
introducer needle to move past the lock in a proximal direction but
prevents movement of the discontinuous portion past the lock in a
distal direction. Such a lock can take many forms and can include a
spring gate, a leaf spring with one or a plurality of locking legs,
where the locking legs have a variety of configurations, a tube
having one or more inwardly and proximally directed tabs, a speed
nut with one or more radially inwardly and proximally directed tabs
extending from the main body or a retention plate with one or more
radially inwardly directed tabs formed around the main body.
[0019] The spring gate has a generally U shaped configuration with
a pair of spaced apart tines. The introducer needle is disposed
between the tines and is moveable longitudinally past the tines. A
biasing mechanism forces the spring gate up into contact with the
introducer needle. With this embodiment, the discontinuous portion
on the needle is preferably an enlarged diameter portion. A tapered
portion immediately proximal of the enlarged diameter portion on
the introducer needle may be used to facilitate proximal movement
of the enlarged diameter portion past the spring gate. The enlarged
diameter portion could be formed with a distally facing shoulder to
provide a further positive engagement with the spring gate and
minimize the possibility that a clinician could force the sharp
distal tip of the introducer needle distally out of the needle
shield during normal use and under normal conditions.
[0020] When the introducer needle is withdrawn proximally into the
needle shield, the introducer needle rides past the tines of the
spring gate. As the enlarged diameter portion passes by the tines,
the enlarged diameter portion engages the tines. This forces the
spring gate to rotate toward the proximal end of the introducer
needle. The spring gate is also forced downwardly against the bias
of the biasing mechanism. This movement by the spring gate allows
the enlarged diameter portion of the introducer needle to move
proximally past the spring gate. Once the enlarged diameter portion
is proximal of the spring gate the biasing mechanism forces the
spring gate upwardly and the tines of the spring gate rotate toward
the distal end of the introducer needle. This movement of the
spring gate ensures that the main portion of the introducer needle
is located in the space between the tines of the spring gate so the
tines extend up past the introducer needle. In this position, the
spring gate abuts a proximal facing surface of a shoulder or wall
in the housing to prevent further distal rotation of the spring
gate. Thus, if a clinician tries to advance the introducer needle
distally, the enlarged diameter portion would engage the tines of
the spring gate. In addition, the spring gate would engage the wall
or shoulder in the housing and prevent the introducer needle from
being moved distally.
[0021] Another lock that may be used to prevent unwanted distal
movement of the introducer needle once the sharp distal tip of the
introducer needle has been proximally withdrawn into the introducer
needle shield is a leaf spring. With the leaf spring, any
configuration for the discontinuous portion can be used. However,
preferably the discontinuous portion is an enlarged diameter
portion on the introducer needle with a distally facing shoulder
when the leaf spring is used.
[0022] The leaf spring has a proximal wall, a support leg and at
least one locking leg. Preferably, the support leg and the locking
leg are configured such that the locking leg extends generally back
toward the proximal end of the support leg. In this configuration
the support leg and the locking leg have a generally V-shape, with
the apex of the V facing distally. Although this configuration is
preferred, any other configuration that biases the locking leg
toward the introducer needle could be used. For example, the
locking leg could be generally perpendicular to the support leg or
oriented at some other angle less than 90 degrees. Alternatively,
the locking leg could be formed so it has a generally U-shaped or
V-shaped configuration with a pair of spaced apart tines. With such
a configuration the locking legs prevent unwanted distal movement
of the introducer needle in a manner analogous to the spring gate
discussed above. In addition, the portion of the locking leg that
rides along the introducer needle shaft could be contoured to
approximate a portion of the circumference of the introducer needle
to minimize drag as the introducer needle rides past the locking
leg.
[0023] The configuration of the leaf spring ensures that the
locking leg is biased toward and abuts the main portion of the
introducer needle. However this bias still allows the locking leg
to ride over the enlarged diameter portion as the introducer needle
is moved proximally into the needle shield. Once the distally
facing shoulder of the enlarged diameter portion is moved
proximally of the locking leg, the locking leg moves back into
contact with the main portion of the introducer needle. Thereafter,
if the introducer needle is moved distally, the locking leg will
engage the distally facing shoulder and prevent further distal
movement of the introducer needle.
[0024] The leaf spring and housing could be configured to maximize
the mechanical engagement force between the locking leg and the
introducer needle. For example, the cavity where the lock is
located could have a tapered cross-section and the leaf spring
could be disposed therein so it could move distally into the
tapered cross-section.
[0025] In this embodiment of the leaf spring, the introducer needle
would be proximally withdrawn into the needle shield just like in
the previous embodiments until the discontinuous portion is
proximal of the locking leg. Thereafter, if the introducer needle
is moved distally, the locking leg engages the discontinuous
portion and causes the lock to move distally into the tapered
cross-section of the cavity. This causes the leaf spring to engage
the introducer needle with increasing force until the tapered
cross-section prevents further distal movement of the leaf spring.
At this point, the locking leg forcefully engages the discontinuous
portion preventing distal movement of the introducer needle.
[0026] In order to minimize drag on the introducer needle, the
locking leg could be initially spaced apart from the introducer
needle. In an alternate embodiment, the locking leg could be held
out of engagement with the introducer needle by a finger and tab
arrangement on the leaf spring and the housing. The leaf spring is
movable proximally with respect to the housing by the engagement of
the discontinuous portion of the introducer needle with the
proximal wall of the leaf spring so the finger and tab can be moved
out of engagement with one another. This allows the locking leg to
move into engagement with the introducer needle by the inward bias
of the locking leg. Thereafter, unwanted distal movement is
prevented as discussed above.
[0027] In another embodiment of the leaf spring, the cavity has a
distal portion and a proximal portion where the diameter of the
distal portion is larger than the diameter of the proximal portion.
The leaf spring is disposed in the cavity for proximal movement
from the distal portion to the proximal portion. When the leaf
spring is disposed in the distal portion, the locking leg does not
engage the introducer needle. As the introducer needle is withdrawn
proximally into the needle shield, the discontinuous portion of the
introducer needle engages the proximal wall of the leaf spring.
This engagement causes the leaf spring to move proximally with the
introducer needle into the proximal portion of the cavity until the
proximal wall of the leaf spring abuts the proximal wall of the
housing. At this point, any further proximal movement of the leaf
spring and the introducer needle is prevented.
[0028] When the leaf spring is in the proximal portion, the walls
defining the cavity force the locking legs inwardly into engagement
with the introducer needle. The leaf spring includes flexible,
outwardly extending fingers. The inner walls of the proximal
portion in the cavity define slots having a proximally facing wall
for receiving the fingers. When the leaf spring is in the proximal
portion so the proximal wall of the leaf spring abuts the proximal
wall of the housing, the fingers are located in the slots so they
are proximal of the proximally facing wall. Thus distal movement of
the leaf spring is prevented by the engagement of the fingers and
the proximally facing wall. As a result when the discontinuous
portion of the introducer needle engages the locking leg, distal
movement of the introducer needle is prevented.
[0029] Alternatively, the locking leg can be oriented so it is
generally perpendicular to the support leg and can be formed with a
small diameter opening formed therein. This opening is too small to
allow the enlarged diameter portion on the introducer needle to
pass therethrough but is large enough to allow the main portion of
the introducer needle to pass through.
[0030] The leaf spring is held in a biased position by the shaft of
the introducer needle. Thus, the locking leg rides along the
introducer needle shaft as the introducer needle is retracted into
the needle shield. Once the distal end of the introducer needle has
been retracted into the needle shield and is proximal of the
locking leg, the leaf spring returns to its unbiased position. As
such, the locking leg can move so the small diameter opening in the
locking leg will be aligned with the sharp distal tip of the
introducer needle. Thus, if the introducer needle is moved distally
with respect to the leaf spring, the distal end of the introducer
needle travels through and past the small diameter opening formed
in the locking leg. However, the introducer needle is prevented
from being moved distally outside of the needle shield when the
enlarged diameter portion on the introducer needle engages the
small diameter opening formed in the locking leg.
[0031] Preferably, the housing includes at least one additional
medial wall adjacent to the locking leg. This medial wall includes
an opening therein to allow the main portion of the introducer
needle to extend through the medial wall. This provides additional
support for the introducer needle and ensures that the introducer
needle is aligned with the small diameter opening in the locking
leg when the leaf spring returns to its unbiased position.
[0032] A variation of the foregoing leaf spring includes an opening
in the locking leg with a diameter slightly larger than the
diameter of the enlarged diameter portion of the introducer needle.
The leaf spring also includes a proximal wall defining an opening
therein slightly larger than the diameter of the shaft of the
introducer needle but smaller than the diameter of the enlarged
diameter portion. The leaf spring is also slidably disposed in the
housing of the needle shield but has an end portion of the locking
leg that is substantially held in place with respect to the
housing. This allows the locking leg to rotate in the housing.
[0033] Prior to use when the sharp distal tip of the introducer
needle extends beyond the distal end of the needle shield, the
locking leg is perpendicular to the longitudinal axis of the
introducer needle. In this position, the introducer needle extends
through the opening in the proximal wall and the opening in the
locking leg. Since the diameter of the opening in the locking leg
is slightly larger than the diameter of the enlarged diameter
portion, it can be retracted through the opening in the locking leg
so the enlarged diameter portion is proximal of the locking
leg.
[0034] Once the enlarged diameter portion of the introducer needle
engages the opening in the proximal wall, the leaf spring moves
proximally with the introducer needle until the proximal wall of
the leaf spring abuts the proximal wall of the housing. Because one
end of the locking leg is substantially held in place with respect
to the housing, this proximal movement of the leaf spring causes
the proximal leg to rotate clockwise as seen in the FIGS. This
changes the orientation of the opening in the locking leg so that a
plane defining that opening is no longer perpendicular to the
longitudinal axis of the introducer needle. Instead, the opening is
angled so that the effective diameter of the opening, i.e. the
perpendicular dimension of the opening, is less than the diameter
of the enlarged diameter portion. In addition, in this position, a
detent associated with the leaf spring prevents subsequent distal
movement of the leaf spring. Thus any subsequent distal movement of
the introducer needle is prevented since the enlarged diameter
portion cannot be moved through the opening in the locking leg.
[0035] An alternative lock that prevents distal movement of the
sharp distal tip of the introducer needle out of the distal end of
the needle shield once the sharp distal tip has been proximally
withdrawn into the needle shield is a tube formed in the housing.
Again, although most forms of the discontinuous portion could be
used with this embodiment, the discontinuous portion is preferably
an enlarged diameter portion with a distally facing shoulder. The
tube is located inside the housing to allow the introducer needle
to pass therethrough and includes at least one movable lanced
protrusion or tab that extends proximally and inwardly into the
tube. Preferably the lanced protrusion, or tab is biased inwardly.
Because the lanced protrusion or tab is movable, the enlarged
diameter portion of the introducer needle with the distally facing
shoulder can move proximally past the lanced protrusion or tab.
Once the introducer needle has been withdrawn proximally into the
needle shield such that the lanced protrusion or tab is distal of
the distally facing shoulder, unwanted distal movement of the
introducer needle will be prevented when the distally facing
shoulder engages the lanced protrusion or tab.
[0036] Although the enlarged diameter portion having a distally
facing shoulder is the preferred embodiment for the discontinuous
portion, a notch formed in the introducer needle could be used as
the discontinuous portion. When the introducer needle is withdrawn
proximally into the needle shield, one of the lanced protrusions or
tabs extends into the notch. Thereafter, distal movement of the
introducer needle is prevented when the lanced protrusion or tab
engages the proximal edge of the notch.
[0037] Yet another lock that prevents distal movement of the sharp
distal tip of the introducer needle out of the distal end of the
needle shield once the sharp distal tip has been proximally
withdrawn into the needle shield is a speed nut that is formed in
or added to the housing. The speed nut is located in the housing
and defines a through hole and at least one proximally oriented and
radially inwardly extending tab adjacent the through hole. The
through hole should be slightly larger than the diameter of the
introducer needle to allow the main portion of the introducer
needle to pass therethrough. Because the tab is proximally
oriented, the discontinuous portion can move proximally past the
tab.
[0038] Once the introducer needle has been withdrawn proximally
into the needle shield such that the tab is distal of the
discontinuous portion, any distal movement of the introducer needle
will be prevented when the discontinuous portion engages the tab.
If an enlarged diameter portion were used for the discontinuous
portion, it would be desirable to include a distally facing
shoulder on the enlarged diameter portion to ensure firm engagement
with the tab. Alternatively, the discontinuous portion may be a
notch formed in the needle. When the introducer needle is
proximally withdrawn into the needle shield the tab drops into the
notch to thereby prevent any further distal movement of the needle
when the tab engages the proximal edge of the notch. To avoid
difficulties in aligning the tab and the notch, the speed nut could
be formed with a plurality of tabs, each of which is configured to
engage the notch. Alternatively, the introducer needle could be
formed with a plurality of longitudinally displaced notches located
around the circumference of the introducer needle.
[0039] In still another embodiment of the lock that prevents distal
movement of the sharp distal tip of the introducer needle out of
the distal end of the needle shield once the sharp distal tip has
been proximally withdrawn into the needle shield, a retention plate
is located on a proximal face of a medial wall formed in the
housing. The wall defines an opening therein that has a diameter
large enough to allow the introducer needle and the discontinuous
portion to pass through. The retention plate defines at least one,
but preferably a plurality of radially inwardly directed tabs. A
cut out portion that has a radius substantially equal to or
slightly larger than the radius of the main portion of the
introducer needle but less than the radius of the enlarged diameter
portion is defined between the tabs. In this embodiment, the
discontinuous portion is preferably an enlarged diameter portion
with a distally facing shoulder. As the introducer needle is
withdrawn into the needle shield, the main portion of the
introducer needle rides past the retention plate with little or no
interference. As the introducer needle moves proximally with
respect to the needle shield, the enlarged diameter portion of the
introducer needle engages the retention plate and the tabs flex
proximally so the enlarged diameter portion can travel proximally
past the retention plate. Once the enlarged diameter portion of the
needle is proximal of the retention plate, the tabs return to their
unflexed position and abut the proximal face of the medial wall.
Any subsequent distal movement of the introducer needle is
prevented when the enlarged diameter portion engages the tabs of
the retention plate since the housing wall prevents the tabs from
flexing distally out of the way of the enlarged diameter
portion.
[0040] The means for preventing further proximal movement of the
introducer needle once the sharp distal tip of the introducer
needle has been proximally withdrawn into the needle shield may
take a number of forms. For example, where the discontinuous
portion is an enlarged diameter portion, the housing may include a
proximal opening that has a diameter sufficient to allow the main
portion of the introducer needle to extend therethrough but that is
too small to allow the enlarged diameter portion of the introducer
needle from passing therethrough. Alternatively, regardless of the
configuration of the discontinuous portion of the introducer needle
or where no discontinuous portion is used on the introducer needle,
a tether connected to the needle hub and the needle shield could be
used.
[0041] The needle shield also preferably includes a spring clip
that connects the needle shield to the catheter hub and that
maintains this connection until the sharp distal tip of the
introducer needle has been withdrawn into the needle shield and
locked in place. This spring clip can take many forms.
[0042] In one embodiment, the needle shield includes a spring clip
that has a clip arm that engages the catheter hub. The spring clip
is biased to a position where the clip arm does not engage the
catheter hub. The spring clip is held in a biased position where
the clip arm engages the catheter hub by the introducer needle
shaft. Thus, as long as the introducer needle extends distally past
the spring clip, the clip arm remains engaged with the catheter hub
and the catheter hub stays connected with the needle shield. Once
the sharp distal tip of the introducer needle is withdrawn
proximally past the spring clip, the clip arm moves out of
engagement with the catheter hub. This allows the catheter hub to
be separated from the needle shield. This configuration ensures
that the needle shield remains engaged with the catheter until the
introducer needle has been completely removed from the catheter and
is safely shielded in the needle shield.
[0043] The spring clip can be used in combination with any of the
locks discussed above for preventing unwanted distal movement of
the introducer needle with respect to the needle shield. In
addition, the spring clip can be formed integrally with or
separately from any of those locks.
[0044] The specific configuration of the spring clip can take many
different forms and can be oriented in the housing in many
different ways. For example, the spring clip can have a generally V
or U shaped configuration. In this embodiment, the spring clip is
located in the housing so it is perpendicular to the longitudinal
axis of the introducer needle such that the V or U configuration is
readily apparent from an end cross-sectional view of the needle
shield. Thus one leg of the V is held in its biased position,
adjacent to the other leg, by direct contact with the shaft of the
introducer needle. In this arrangement, the spring clip includes a
clip arm that extends generally parallel to the longitudinal axis
of the introducer needle and engages a detent on the catheter hub
that is oriented generally perpendicular to the longitudinal axis
of the clip arm. When the introducer needle is withdrawn proximal
of the spring clip, it returns to its unbiased position such that
the clip arm moves transversely, i.e. generally perpendicularly to
the longitudinal axis of the introducer needle, out of engagement
with the catheter hub.
[0045] In an alternate embodiment, the spring clip is generally
straight and is flexed into its biased position by the shaft of the
introducer needle. In this embodiment, the clip arm has a hook
configuration with one leg of the hook extending perpendicular to
the longitudinal axis of the introducer needle with the hook facing
distally. When the introducer needle is moved proximal of the
spring clip, it returns to its unbiased position such that the clip
arm moves transversely out of engagement with the catheter hub.
[0046] The spring clip can also be generally V or U shaped but
oriented in the housing so it is aligned with the longitudinal axis
of the introducer needle such that in a top cross-sectional view of
the needle shield, the V or U configuration is apparent. In this
configuration, the clip arm extends generally parallel to the
longitudinal axis of the introducer needle and directly engages the
catheter hub. However, a separate biasing arm extending generally
perpendicular to the longitudinal axis of the introducer needle and
connected to each of the legs of the V or U is required so the
introducer needle can bias the spring clip into engagement with the
catheter hub. Each biasing arm defines an opening therein and
through which the introducer needle extends to achieve this biasing
requirement. Once the introducer needle is moved proximal of the
biasing arm, the legs of the spring clip can move to their unbiased
position out of engagement with the catheter hub. Alternatively,
the spring clip may be formed with only one leg such that the
spring clip has a generally L-shaped shaped configuration.
[0047] Where the leaf spring uses a locking leg that is generally
perpendicular to the introducer needle, the spring clip can be
associated with the locking leg. The spring clip can be pivotally
connected to the needle shield housing such that it is caused to
pivot between a clipped position and an unclipped position by the
movement of the locking leg. Alternatively, the spring clip can be
formed as a hook extending distally from the locking leg such that
movement of the locking leg from the unshielded to the shielded
position causes the hook to move from a clipped position to an
unclipped position.
[0048] With the foregoing embodiments using a biasing arm, a means
for minimizing drag on the introducer needle may be used. Such a
means is a flap or finger extending from the opening in the biasing
arm generally parallel to the longitudinal axis of the introducer
needle. Alternatively, where two biasing arms are used, a pin and
tether combination can be used. The pin extending through the
biasing arms holds the openings in proper alignment so the
introducer needle does not catch on the sides of the openings. A
tether connected to the pin and the needle hub pulls the pin out of
the biasing arms and allows the spring clip to return to its
unbiased position.
[0049] Where two biasing arms are used, interlocking fingers may be
located on the ends of the biasing arms such that, once the
introducer needle is withdrawn proximal of the biasing arms, the
interlocking fingers lock together to ensure that a non-defeatable
transverse barrier is formed by the biasing arms.
[0050] In still another embodiment of the spring clip, the spring
clip can be formed with a generally X shaped configuration. In this
embodiment, the spring clip is oriented in the housing so the X
shape is aligned with the longitudinal axis of the introducer
needle such that in a top cross-sectional view of the needle
shield, the X shape of the spring clip is apparent. In this
embodiment, the introducer needle holds the distal portion of the
legs of the X apart so they engage the inside of the catheter hub.
Thus, once the introducer needle is withdrawn proximal of the
intersection of the legs, the distal portion of the legs can move
inwardly out of engagement with the catheter hub.
[0051] With all of the foregoing embodiments, the clip arm can be
configured so it engages either the inside or the outside of the
catheter hub. In addition, the clip arm can be configured
frictionally or mechanically to engage the catheter hub. If a
mechanical engagement is desired, the clip arm can have a detent
thereon that engages a complementary detent formed on the catheter
hub. Complementary detents can include, for example, a slot and a
finger, or a post of any geometric shape. Regardless of the
specific configuration used, the main requirement is to have the
clip arm engage the catheter hub so it is difficult for the
clinician to remove the catheter hub from the needle shield until
the sharp distal tip of the introducer needle is shielded in the
needle shield.
BRIEF DESCRIPTION OF THE DRAWINGS
[0052] The preferred embodiments are illustrated in the drawings in
which like reference numerals refer to like elements and in
which:
[0053] FIG. 1 is a perspective view of a standard catheter and
introducer needle assembly with the needle shield of this invention
with the catheter in partial cross-section;
[0054] FIG. 2 is a perspective view of an integrated catheter and
introducer needle assembly with the needle shield of this
invention;
[0055] FIG. 3A is an enlarged elevation view of the distal portion
of the introducer needle with one embodiment of the discontinuous
portion thereon used in the catheter and introducer needle assembly
with the needle shield of this invention;
[0056] FIG. 3B is an enlarged elevation view of the distal portion
of the introducer needle with a second embodiment of the
discontinuous portion thereon used in the catheter and introducer
needle assembly with the needle shield of this invention;
[0057] FIG. 3C is an enlarged elevation view of the distal portion
of the introducer needle with a third embodiment of the
discontinuous portion thereon used in the catheter and introducer
needle assembly with the needle shield of this invention;
[0058] FIG. 3D is an enlarged elevation view of the distal portion
the introducer needle with a fourth embodiment of the discontinuous
portion thereon used in the catheter and introducer needle assembly
with the needle shield of this invention;
[0059] FIG. 3E is an enlarged elevation view of the distal portion
of the introducer needle with a fifth embodiment of the
discontinuous portion thereon used in the catheter and introducer
needle assembly with the needle shield of this invention;
[0060] FIG. 3F is an enlarged elevation view of the distal portion
of the introducer needle with a sixth embodiment of the
discontinuous portion thereon used in the catheter and introducer
needle assembly with the needle shield of this invention;
[0061] FIG. 3G is an enlarged elevation view of the distal portion
of the introducer needle with a seventh embodiment of the
discontinuous portion thereon used in the catheter and introducer
needle assembly with the needle shield of this invention;
[0062] FIG. 4 is a cross-sectional view of the needle shield with a
first embodiment of the lock that prevents unwanted distal movement
of the introducer needle and the distal portion of the introducer
needle with the sharp distal tip of the introducer needle extending
from the distal end of the needle shield;
[0063] FIG. 5 is a cross-sectional view of the needle shield with
the first embodiment of the lock that prevents unwanted distal
movement of the introducer needle and the distal portion of the
introducer needle with the sharp distal tip of the introducer
needle withdrawn into the needle shield;
[0064] FIG. 6 is a cross-sectional view of the needle shield with
the first embodiment of the lock that prevents unwanted distal
movement of the introducer needle and the distal portion of the
introducer needle with the sharp distal tip of the introducer
needle locked in the needle shield;
[0065] FIG. 7 is a perspective view of the spring gate that is used
in the first embodiment of the lock shown in FIGS. 4 through 6 that
prevents unwanted distal movement of the introducer needle;
[0066] FIG. 8 is a perspective cross-sectional view of the needle
shield with a second embodiment of the lock that prevents unwanted
distal movement of the introducer needle and the distal portion of
the introducer needle with the sharp distal tip of the introducer
needle extending from the distal end of the needle shield;
[0067] FIG. 9 is a cross-sectional view of the needle shield with
the second embodiment of the lock that prevents unwanted distal
movement of the introducer needle and the distal portion of the
introducer needle with the sharp distal tip of the introducer
needle locked in the needle shield;
[0068] FIG. 10 is a perspective view of the leaf spring that is the
second embodiment of the lock shown in FIGS. 8 and 9 that prevents
unwanted distal movement of the introducer needle;
[0069] FIG. 11 is a perspective cross-sectional view of the needle
shield with a third embodiment of the lock that prevents unwanted
distal movement of the introducer needle and the distal portion of
the introducer needle with the sharp distal tip of the introducer
needle extending from the distal end of the needle shield;
[0070] FIG. 12 is a cross-sectional view of the needle shield with
the third embodiment of the lock that prevents unwanted distal
movement of the introducer needle and the distal portion of the
introducer needle with the sharp distal tip of the introducer
needle locked in the needle shield;
[0071] FIG. 13 is a perspective view of the leaf spring that is the
third embodiment of the lock shown in FIGS. 11 and 12 that prevents
unwanted distal movement of the introducer needle;
[0072] FIG. 14 is a schematic cross-sectional view of the needle
shield with a fourth embodiment of the lock that prevents unwanted
distal movement of the introducer needle and the distal portion of
the introducer needle with the sharp distal tip of the introducer
needle extending from the distal end of the needle shield;
[0073] FIG. 15 is a schematic cross-sectional view of the needle
shield with the fourth embodiment of the lock that prevents
unwanted distal movement of the introducer needle and the distal
portion of the introducer needle with the sharp distal tip of the
introducer needle locked in the needle shield;
[0074] FIG. 16 is a schematic cross-sectional view of the needle
shield with the fifth embodiment of the lock that prevents unwanted
distal movement of the introducer needle and the distal portion of
the introducer needle with the sharp distal tip of the introducer
needle extending from the distal end of the needle shield;
[0075] FIG. 17 is a schematic cross-sectional view of the needle
shield with a sixth embodiment of the lock that prevents unwanted
distal movement of the introducer needle and the distal portion of
the introducer needle with the sharp distal tip of the introducer
needle extending from the distal end of in the needle shield;
[0076] FIG. 18 is a schematic cross-sectional view of the needle
shield with the sixth embodiment of the lock that prevents unwanted
distal movement of the introducer needle and the distal portion of
the introducer needle with the sharp distal tip of the introducer
needle locked in the needle shield;
[0077] FIG. 19 is a perspective cross-sectional view of the needle
shield with a seventh embodiment of the lock that prevents unwanted
distal movement of the introducer needle and the distal portion of
the introducer needle with the sharp distal tip of the introducer
needle extending from the distal end of in the needle shield;
[0078] FIG. 20 is a perspective cross-sectional view of the needle
shield with the seventh embodiment of the lock that prevents
unwanted distal movement of the introducer needle and the distal
portion of the introducer needle with the sharp distal tip of the
introducer needle locked in the needle shield;
[0079] FIG. 21 is a perspective view of the leaf spring that is the
seventh embodiment of the lock shown in FIGS. 19 and 20 that
prevents unwanted distal movement of the introducer needle;
[0080] FIG. 22 is a schematic cross-sectional view of the needle
shield with an eighth embodiment of the lock that prevents unwanted
distal movement of the introducer needle and the distal portion of
the introducer needle with the sharp distal tip of the introducer
needle extending from the distal end of in the needle shield;
[0081] FIG. 23 is a schematic cross-sectional view of the needle
shield with the eighth embodiment of the lock that prevents
unwanted distal movement of the introducer needle and the distal
portion of the introducer needle with the sharp distal tip of the
introducer needle locked in the needle shield;
[0082] FIG. 24 is a distal end view of the leaf spring that is the
eighth embodiment of the lock that prevents unwanted distal
movement of the introducer needle having the orientation shown in
FIG. 22;
[0083] FIG. 25 is a distal end view of the leaf spring that is the
eighth embodiment of the lock that prevents unwanted distal
movement of the introducer needle having the orientation shown in
FIG. 23;
[0084] FIG. 26 is a cross-sectional view of the needle shield with
a ninth embodiment of the lock that prevents unwanted distal
movement of the introducer needle and the distal portion of the
introducer needle with the sharp distal tip of the introducer
needle extending from the distal end of the needle shield;
[0085] FIG. 27 is a cross-sectional view of the needle shield with
the ninth embodiment of the lock that prevents unwanted distal
movement of the introducer needle and the distal portion of the
introducer needle with the sharp distal tip of the introducer
needle locked in the needle shield;
[0086] FIG. 28 is a perspective cross-sectional view of the tube
that is the ninth embodiment of the lock shown in FIGS. 26 and 27
to prevent unwanted distal movement of the introducer needle;
[0087] FIG. 29 is a cross-sectional view of the needle shield with
a tenth embodiment of the lock that prevents unwanted distal
movement of the introducer needle and the distal portion of the
introducer needle with the sharp distal tip of the introducer
needle extending from the distal end of in the needle shield;
[0088] FIG. 30 is a cross-sectional view of the needle shield with
the tenth embodiment of the lock that prevents unwanted distal
movement of the introducer needle and the distal portion of the
introducer needle with the sharp distal tip of the introducer
needle locked in the needle shield;
[0089] FIG. 31 is a cross-sectional view of the needle shield with
the tenth embodiment of the lock that prevents unwanted distal
movement of the introducer needle and the distal portion of the
introducer needle shown in FIG. 3F with the sharp distal tip of the
introducer needle locked in the needle shield;
[0090] FIG. 32 is a perspective view of the speed nut that is the
tenth embodiment of the lock shown in FIGS. 29 through 31 to
prevent unwanted distal movement of the introducer needle;
[0091] FIG. 33 is an exploded perspective view of a catheter,
introducer needle and the needle shield with an eleventh embodiment
of the lock that prevents unwanted distal movement of the
introducer needle and a first embodiment of the spring clip that
connects the needle shield to the catheter hub until the sharp
distal tip of the introducer needle is locked in the needle
shield;
[0092] FIG. 34 is a partial cross-sectional view of the needle
shield with the eleventh embodiment of the lock that prevents
unwanted distal movement of the introducer needle, the first
embodiment of the spring clip that connects the needle shield to
the catheter hub until the sharp distal tip of the introducer
needle is locked in the needle shield, a portion of the introducer
needle and the proximal portion of the catheter hub with the sharp
distal tip of the introducer needle extending from the distal end
of in the needle shield and the needle shield connected to the
catheter hub;
[0093] FIG. 35 is a partial cross-sectional view of the needle
shield with the eleventh embodiment of the lock that prevents
unwanted distal movement of the introducer needle, the first
embodiment of the spring clip that connects the needle shield to
the catheter hub until the sharp distal tip of the introducer
needle is locked in the needle shield, the distal portion of the
introducer needle and the proximal portion of the catheter hub with
the sharp distal tip of the introducer needle locked in the needle
shield and the needle shield disconnected from the catheter
hub;
[0094] FIG. 36A is a perspective view of the first embodiment of
the spring clip shown in FIGS. 33 through 35 that connects the
needle shield to the catheter hub until the sharp distal tip of the
introducer needle is locked in the needle shield;
[0095] FIG. 36B is a perspective view of a variation of the first
embodiment of the spring clip shown in FIG. 36A that connects the
needle shield to the catheter hub until the sharp distal tip of the
introducer needle is locked in the needle shield;
[0096] FIG. 36C is a perspective view of still another variation of
the first embodiment of the spring clip shown in FIG. 36 that
connects the needle shield to the catheter hub until the sharp
distal tip of the introducer needle is locked in the needle
shield;
[0097] FIG. 37A is a perspective view of the retention plate that
is the eleventh embodiment of the lock shown in FIGS. 33 through 35
that prevents unwanted distal movement of the introducer
needle;
[0098] FIG. 37B is a schematic view, in partial cross-section, of a
variation of the retention plate shown in FIG. 37A abutting the
proximal face of the medial wall of the housing for the needle
shield;
[0099] FIG. 37C is a schematic view, in partial cross-section, of
still another variation of the retention plate shown in FIG. 37A
abutting the proximal face of the medial wall of the housing for
the needle shield;
[0100] FIG. 38 is a cross-sectional view of the needle shield shown
in FIG. 34 taken along line 38-38 showing how the clip arm of the
spring clip would move along a ramp formed in the housing;
[0101] FIG. 39 is a cross-sectional view of the needle shield shown
in FIG. 35 taken along line 39-39 showing how the clip arm of the
spring clip would move along a ramp formed in the housing;
[0102] FIG. 40 is a schematic perspective view of a first
embodiment of the spring clip with a transverse barrier that
connects the needle shield to the catheter hub until the sharp
distal tip of the introducer needle is locked in the needle shield
and a portion of the introducer needle and a portion of the
catheter hub where the sharp distal tip of the introducer needle
would be extending from the distal end of the needle shield and the
needle shield would be connected to the catheter hub;
[0103] FIG. 41 is a schematic perspective view of the spring clip
shown in FIG. 40 where the sharp distal tip of the introducer
needle would be locked in the needle shield and the needle shield
would be disconnected from the catheter hub;
[0104] FIG. 42 is an exploded perspective view of a catheter,
introducer needle, tether and the needle shield with a second
embodiment of a spring clip with a transverse barrier that connects
the needle shield to the catheter hub until the sharp distal tip of
the introducer needle is locked in the needle shield;
[0105] FIG. 43 is a cross-sectional view of the needle shield with
the second embodiment of the spring clip with a transverse barrier
that connects the needle shield to the catheter hub until the sharp
distal tip of the introducer needle is locked in the needle shield,
a portion of the introducer needle, the tether, the needle shield,
and the proximal portion of the catheter hub with the sharp distal
tip of the introducer needle extending from the distal end of the
needle shield and the needle shield connected to the catheter
hub;
[0106] FIG. 44 is a cross-sectional view of the needle shield with
the second embodiment of the spring clip with a transverse barrier
that connects the needle shield to the catheter hub until the sharp
distal tip of the introducer needle is locked in the needle shield,
the distal portion of the needle hub, the distal portion of the
introducer needle, the tether, and the proximal portion of the
catheter hub with the sharp distal tip of the introducer needle
locked in the needle shield and the needle shield disconnected from
the catheter hub;
[0107] FIG. 45 is a perspective view of the second embodiment of
the spring clip with a transverse barrier shown in FIGS. 42 through
44;
[0108] FIG. 46 is an exploded perspective view of an integrated
catheter, an introducer needle and the needle shield with a first
embodiment of an integrated clip lock that connects the needle
shield to the catheter hub until the sharp distal tip of the
introducer needle is locked in the needle shield and that prevents
unwanted distal movement of the introducer needle;
[0109] FIG. 47 is a perspective partial cross-sectional view of the
needle shield with the first embodiment of the integrated clip lock
that connects the needle shield to the catheter hub until the sharp
distal tip of the introducer needle is locked in the needle shield
and that prevents unwanted distal movement of the introducer
needle, a portion of the introducer needle and the proximal portion
of the catheter hub with the sharp distal tip of the introducer
needle extending from the distal end of the needle shield and the
needle shield connected to the catheter hub;
[0110] FIG. 48 is a perspective partial cross-sectional view of the
needle shield with the first embodiment of the integrated clip lock
that connects the needle shield to the catheter hub until the sharp
distal tip of the introducer needle is locked in the needle shield
and that prevents unwanted distal movement of the introducer
needle, the distal portion of the introducer needle and the
proximal portion of the catheter hub with the sharp distal tip of
the introducer needle locked in the needle shield and the needle
shield disconnected from the catheter hub;
[0111] FIG. 49 is a perspective view of the first embodiment of the
integrated clip lock that is shown in FIGS. 46 through 48 that
connects the needle shield to the catheter hub until the sharp
distal tip of the introducer needle is locked in the needle shield
and that prevents unwanted distal movement of the introducer
needle;
[0112] FIG. 50 is a perspective view of a third embodiment of a
spring clip with a transverse barrier that connects the needle
shield to the catheter hub until the sharp distal tip of the
introducer needle is locked in the needle shield;
[0113] FIG. 51 is a perspective partial cross-sectional view of a
fourth embodiment of a spring clip with a transverse barrier that
connects the needle shield to the catheter hub until the sharp
distal tip of the introducer needle is locked in the needle shield,
a portion of the introducer needle, a portion of the tether and the
proximal portion of the catheter hub with the sharp distal tip of
the introducer needle extending from the distal end of in the
needle shield and the needle shield connected to the catheter hub
and a first embodiment of an interlock that prevents defeat of the
transverse barrier;
[0114] FIG. 52 is a perspective partial cross-sectional view of the
needle shield with the fourth embodiment of the spring clip with a
transverse barrier that connects the needle shield to the catheter
hub until the sharp distal tip of the introducer needle is locked
in the needle shield, the distal portion of the introducer needle,
the distal portion of the tether and the proximal portion of the
catheter hub with the sharp distal tip of the introducer needle
locked in the needle shield and the needle shield disconnected from
the catheter hub and a first embodiment of an interlock that
prevents defeat of the transverse barrier;
[0115] FIG. 53 is a perspective view of the fourth embodiment of
the spring clip with a transverse barrier that is used in the
needle shield shown in FIGS. 51 and 52 to connect the needle shield
to the catheter hub until the sharp distal tip of the introducer
needle is locked in the needle shield and a first embodiment of an
interlock that prevents defeat of the transverse barrier;
[0116] FIG. 54 is a perspective partial cross-sectional view of the
needle shield with a first embodiment of the integrated clip lock
that connects the needle shield to the catheter hub until the sharp
distal tip of the introducer needle is locked in the needle shield
and that prevents unwanted distal movement of the introducer
needle, a portion of the introducer needle and the proximal portion
of the catheter hub with the sharp distal tip of the introducer
needle extending from the distal end of the needle shield and the
needle shield connected to the catheter hub and a first embodiment
of a tethered trigger to disconnect the spring clip from the
catheter hub;
[0117] FIG. 55 is a perspective partial cross-sectional view of the
needle shield with the second embodiment of the integrated clip
lock that connects the needle shield to the catheter hub until the
sharp distal tip of the introducer needle is locked in the needle
shield and that prevents unwanted distal movement of the introducer
needle, a portion of the introducer needle and the proximal portion
of the catheter hub with the sharp distal tip of the introducer
needle extending from the distal end of the needle shield and the
needle shield connected to the catheter hub;
[0118] FIG. 56 is a perspective partial cross-sectional view of the
needle shield with the second embodiment of the integrated clip
lock that connects the needle shield to the catheter hub until the
sharp distal tip of the introducer needle is locked in the needle
shield and that prevents unwanted distal movement of the introducer
needle, the distal portion of the introducer needle and the
proximal portion of the catheter hub with the sharp distal tip of
the introducer needle locked in the needle shield and the needle
shield disconnected from the catheter hub;
[0119] FIG. 57 is a perspective view of the second embodiment of
the integrated clip lock shown in FIGS. 55 and 56 to connect the
needle shield to the catheter hub until the sharp distal tip of the
introducer needle is locked in the needle shield and to prevent
unwanted distal movement of the introducer needle;
[0120] FIG. 58 is a perspective partial cross-sectional view of the
needle shield with a fifth embodiment of a spring clip with a
transverse barrier that connects the needle shield to the catheter
hub until the sharp distal tip of the introducer needle is locked
in the needle shield, a portion of the introducer needle, a portion
of the tether and the proximal portion of the catheter hub with the
sharp distal tip of the introducer needle extending from the distal
end of the needle shield and the needle shield connected to the
catheter hub;
[0121] FIG. 59 is a perspective partial cross-sectional view of the
needle shield with a sixth embodiment of the spring clip with a
transverse barrier that connects the needle shield to the catheter
hub until the sharp distal tip of the introducer needle is locked
in the needle shield, a portion of the introducer needle, a portion
of the tether and the proximal portion of the catheter hub with the
sharp distal tip of the introducer needle extending from the distal
end of in the needle shield with the needle shield connected to the
catheter hub;
[0122] FIG. 60 is a perspective partial cross-sectional view of the
needle shield with the sixth embodiment of the spring clip with a
transverse barrier that connects the needle shield to the catheter
hub until the sharp distal tip of the introducer needle is locked
in the needle shield, the distal portion of the introducer needle,
the distal portion of the tether and the proximal portion of the
catheter hub with the sharp distal tip of the introducer needle
locked in the needle shield and the needle shield disconnected from
the catheter hub;
[0123] FIG. 61 is a perspective view of the sixth embodiment of the
spring clip with a transverse barrier shown in FIGS. 59 and 60 that
connects the needle shield to the catheter hub until the sharp
distal tip of the introducer needle is locked in the needle
shield;
[0124] FIG. 62 is a schematic view of a portion of the clip arm
showing an alternative embodiment for the engagement mechanism
between the needle shield and the catheter hub;
[0125] FIG. 63 is a schematic view of a portion of the clip arm
showing another alternative embodiment for the engagement mechanism
between the needle shield and the catheter hub;
[0126] FIG. 64 is a perspective view of a portion of the biasing
arm showing an alternative embodiment for the engagement mechanism
between the needle and the biasing arm;
[0127] FIG. 65 is a perspective view of a portion of the biasing
arm showing another alternative embodiment for the engagement
mechanism between the needle and the biasing arm;
[0128] FIG. 66 is an exploded perspective view of an integrated
catheter, introducer needle and needle shield with the eleventh
embodiment of the lock that prevents unwanted distal movement of
the introducer needle and the second embodiment of the spring clip
that connects the needle shield to the catheter hub until the sharp
distal tip of the introducer needle is shielded in the needle
shield;
[0129] FIG. 67 is a perspective partial cross-sectional view of the
needle shield with the eleventh embodiment of the lock that
prevents unwanted distal movement of the introducer needle and the
second embodiment of the spring clip that connects the needle
shield to the catheter hub until the sharp distal tip of the
introducer needle is shielded in the needle shield, a portion of
the introducer needle and the proximal portion of the catheter hub
with the sharp distal tip of the introducer needle extending from
the distal end of the needle shield and the needle shield connected
to the catheter hub;
[0130] FIG. 68 is a perspective partial cross-sectional view of the
needle shield with the eleventh embodiment of the lock that
prevents unwanted distal movement of the introducer needle and the
second embodiment of the spring clip that connects the needle
shield to the catheter hub until the sharp distal tip of the
introducer needle is shielded in the needle shield, the distal
portion of the introducer needle and the proximal portion of the
catheter hub with the sharp distal tip of the introducer needle
locked in the needle shield and the needle shield disconnected from
the catheter hub;
[0131] FIG. 69 is a perspective view of the second embodiment of
the spring clip shown in FIGS. 66 through 68 that connects the
needle shield to the catheter hub until the sharp distal tip of the
introducer needle is shielded in the needle shield;
[0132] FIG. 70 is an exploded perspective view of an integrated
catheter, introducer needle and the needle shield with a seventh
embodiment of the spring clip with a transverse barrier that
connects the needle shield to the catheter hub until the sharp
distal tip of the introducer needle is shielded by the needle
shield and a tether;
[0133] FIG. 71 is a perspective partial cross-sectional view of the
needle shield with the seventh embodiment of the spring clip with a
transverse barrier that connects the needle shield to the catheter
hub until the sharp distal tip of the introducer needle is shielded
by the needle shield, a portion of the introducer needle, the
tether and the proximal portion of the catheter hub with the sharp
distal tip of the introducer needle extending from the distal end
of the needle shield and the needle shield connected to the
catheter hub;
[0134] FIG. 72 is a perspective partial cross-sectional view of the
needle shield with the seventh embodiment of the spring clip with a
transverse barrier that connects the needle shield to the catheter
hub until the sharp distal tip of the introducer needle is shielded
by the needle shield, the distal portion of the introducer needle,
the distal portion of the tether and the proximal portion of the
catheter hub with the sharp distal tip of the introducer needle
locked in the needle shield and the needle shield disconnected from
the catheter hub;
[0135] FIG. 73 is a perspective view of the seventh embodiment of
the spring clip with a transverse barrier shown in FIGS. 70 through
72, that connects the needle shield to the catheter hub;
[0136] FIG. 74 is a partial cross-sectional view of the needle
shield with an eighth embodiment of the spring clip with a
transverse barrier that connects the needle shield to the catheter
hub until the sharp distal tip of the introducer needle is shielded
by the needle shield and the distal portion of the introducer
needle and the proximal portion of the catheter hub with the sharp
distal tip of the introducer needle extending from the distal end
of the needle shield with the needle shield connected to the
catheter hub;
[0137] FIG. 75 is a partial cross-sectional view of the needle
shield with the eighth embodiment spring clip with a transverse
barrier that connects the needle shield to the catheter hub until
the sharp distal tip of the introducer needle is shielded by the
needle shield, and the distal portion of the introducer needle and
the proximal portion of the catheter hub with the sharp distal tip
of the introducer needle locked in the needle shield with the
needle shield disconnected from the catheter hub;
[0138] FIG. 76 is a perspective partial cross-sectional view of the
needle shield with a modified version of the seventh embodiment of
the lock that prevents unwanted distal movement of the introducer
needle and the distal portion of the introducer needle with the
sharp distal tip of the introducer needle extending from the distal
end of in the needle shield wherein the needle shield has a clip
that connects the needle shield to the catheter hub until the sharp
distal tip of the introducer needle is shielded by the needle
shield; and
[0139] FIG. 77 is a perspective partial cross-sectional view of the
needle shield with the modified version of the seventh embodiment
of the lock that prevents unwanted distal movement of the
introducer needle and the distal portion of the introducer needle
with the sharp distal tip of the introducer needle locked in the
needle shield wherein the needle shield has a clip that connects
the needle shield to the catheter hub until the sharp distal tip of
the introducer needle is shielded by the needle shield.
DETAILED DESCRIPTION OF THE INVENTION
[0140] As used herein, the term "proximal" refers to a location on
the catheter and introducer needle assembly with the needle shield
of this invention that, during normal use, is closest to the
clinician using the device and farthest from the patient in
connection with whom the device is used. Conversely, the term
"distal" refers to a location on the catheter and introducer needle
assembly of this invention that, during normal use, is farthest
from the clinician using the device and closest to the patient in
connection with whom the device is used.
[0141] As used herein, the term "top", "up" or "upwardly" refers to
a location on the catheter and introducer needle assembly with the
needle shield of this invention that, during normal use, is
radially away from the longitudinal axis of the device and away
from the patient's skin. Conversely, as used herein, the term
"bottom", "down" or "downwardly" refers to a location on the
catheter and introducer needle assembly with the needle shield of
this invention that, during normal use, is radially away from the
longitudinal axis of the device and toward the patient's skin.
[0142] As used herein, the term "in" or "inwardly" refers to a
location with respect to the catheter and introducer needle
assembly with the needle shield of this invention that, during
normal use, is toward the inside of the device. Conversely, as used
herein, the term "out" or "outwardly" refers to a location with
respect to the catheter and introducer needle assembly with the
needle shield of this invention that, during normal use, is toward
the outside of the device.
[0143] This invention is described herein using like reference
numbers for like elements in the different embodiments. Although
this invention is described herein in connection with a typical
peripheral IV catheter as well as a peripheral IV catheter with an
integrated extension tube (an "integrated catheter"), it is to be
understood that this invention is applicable to other catheters.
For example, this invention is applicable to extended dwell
catheters requiring the needle to be connected to the needle hub by
a stylet as well as other medical devices where it is desirable for
a needle to be shielded after use. In addition, while this
invention is satisfied by embodiments in many different forms,
there are shown in the drawings and herein described in detail,
preferred embodiments of the invention with the scope of the
invention measured by the appended claims.
[0144] The catheter and introducer needle assembly of this
invention is identified generally by the numeral 10 and defines a
longitudinal axis extending therethrough. It includes a catheter
assembly 20 and an introducer needle assembly 30 that includes a
needle shield 40. See FIG. 1. Catheter assembly 20 may include an
integrated extension tube 25. See FIG. 2. Such an integrated
catheter is described generally in U.S. Pat. No. 5,697,914. As
noted above, it is to be understood that the needle shield 40 of
this invention can be used in connection with such an integrated
catheter.
[0145] Catheter assembly 20 includes a catheter 21 that has a
proximal end, a distal end and a catheter hub 24 affixed to
catheter proximal end. Suitable materials for catheter 21 include,
but are not limited to, thermoplastic resins such as fluorinated
ethylene propylene (FEP), polytetrafluoroethylene (PTFE),
polyurethane and the like. Preferably, catheter 21 is formed from a
thermoplastic hydrophilic polyurethane that softens with exposure
to physiological conditions present in the patient's body. Suitable
materials for catheter hub 24 include, but are not limited to,
thermoplastic polymeric resins such as polycarbonate, polystyrene,
polypropylene and the like. Catheter hub 24 may include a radially
outwardly extending tab, which is useful for advancing catheter 21
into the patient's blood vessel.
[0146] Introducer needle assembly 30 includes introducer needle 31
having a sharp distal tip 32 defined by a bevel and a proximal end
connected to a needle hub 34. Introducer needle 31 is preferably
formed from stainless steel and has a longitudinal axis that is
generally parallel to the longitudinal axis of catheter and
introducer needle assembly 10. Needle hub 34 can include an
integrated flashback chamber having an open proximal end. Needle
hub 34 may be formed from the same types of materials that are used
to form catheter hub 24. Of course, other materials could be used
to form needle hub 34. Preferably, the open proximal end is closed
to fluid flow by a vented plug 36 that allows air but not fluid to
flow therethrough.
[0147] Introducer needle assembly 30 also includes needle shield
40, which includes housing 41 defining an internal cavity 42
therein. Housing 41 also defines a proximal opening 43 and a distal
opening 45 in communication with internal cavity 42. This allows
introducer needle 31 to extend longitudinally through housing 41.
The diameters of cavity 42, proximal opening 43 and distal opening
45 are at least slightly larger than the diameter of the main
portion of introducer needle 31. This allows introducer needle 31
easily to pass through needle shield 40. Preferably, cavity 42 and
distal opening 45 are at least slightly larger than any
discontinuous portion formed on introducer needle 31 as described
hereinafter. This allows the distal portion of introducer needle 31
to be withdrawn into housing 41 but prevents introducer needle 31
from being withdrawn proximally from needle shield 40 as described
hereinafter.
[0148] Where the spring clip, as described hereinafter, of this
invention is not used, housing 41 may include a radially extending
flange 46 and a plurality of longitudinally extending fingers 47.
Fingers 47 may include radially inwardly directed projections 48.
Fingers 47 and projections 48 engage catheter hub 24 to hold
introducer needle assembly 30 together with catheter assembly 20.
Typically, catheter hub 24 includes a radially projecting thread or
ear 44 at its proximal end to facilitate the connection of another
device thereto. This provides a portion of catheter hub 24 for
fingers 47 and projections 48 to engage so that catheter hub 24 and
introducer needle assembly 30 remain connected until introducer
needle 31 is removed from catheter assembly 20 and is shielded by
needle shield 40.
[0149] Introducer needle 31 includes a discontinuous portion formed
thereon along a distal portion thereof. The discontinuous portion
may take many forms. For example, it can be an enlarged diameter
portion 38, see FIGS. 3A, 3B, 3C and 3G, or a notch 39, see FIGS.
3D and 3G, or a combination of an enlarged diameter portion 38 and
a notch 39, see FIGS. 3E, 3F and 3G. Where the discontinuous
portion 38 is an enlarged diameter portion, the proximal portion
38a may be tapered and the distal portion 38b may be a distally
facing shoulder oriented generally perpendicular to the
longitudinal axis of introducer needle 31. See e.g. FIG. 3A.
Alternatively, distal portion 38b could be tapered. See e.g. FIG.
3C. This taper can be at just about any angle between almost
parallel to and perpendicular to the longitudinal axis of
introducer needle. Preferably, enlarged diameter portion 38, such
as shown in FIGS. 3A, 3C, 3F and 3G, is formed on introducer needle
31 by centerless grinding a larger diameter introducer needle.
Although enlarged diameter portion 38 is shown in the FIGS. as
being circumferentially disposed about the shaft of introducer
needle 31, it is to be understood, that enlarged diameter portion
38 could be formed asymmetrically about the shaft of introducer
needle 31. For example, enlarged diameter portion could be formed
as a crimped portion on introducer needle 31. See FIGS. 3B and 3E.
For the avoidance of doubt, as used herein the term diameter refers
to the length of a straight line passing through the center of an
object.
[0150] Where the discontinuous portion that is used for introducer
needle 31 is enlarged diameter portion 38, it should have a
diameter greater than the diameter of proximal opening 43
regardless of the specific configuration used for enlarged diameter
portion 38. This provides one mechanism to ensure that introducer
needle 31 cannot be pulled in a proximal direction completely out
of needle shield 40. This is because enlarged diameter portion 38
blocks further proximal movement of introducer needle 31 through
proximal opening 43. Alternatively, a washer 49 having an opening
therein with a diameter slightly larger than the diameter of the
main portion of introducer needle 31 but smaller than the diameter
of enlarged diameter portion 38 can be placed into cavity 42
abutting the proximal wall of cavity 42. In this position, the
opening of washer 49 is aligned with proximal opening 43. Thus
washer 49 would prevent enlarged diameter portion 38 from passing
through proximal opening 43.
[0151] Alternatively, if notch 39 were used as the discontinuous
portion or if no discontinuous portion were used on introducer
needle, a tether 50 could be used to connect needle shield 40 with
needle hub 34. See for example FIG. 42. Tether 50 must be
configured such that its effective length will not allow sharp
distal tip 32 to be pulled proximally completely out of needle
shield 40.
[0152] The diameter of enlarged diameter portion 38 preferably
should be at least about 0.002 inches greater than the outside
diameter of the main portion of introducer needle 31. It has been
surprisingly found that this dimension is sufficient, in the
context of this invention, to prevent sharp distal tip 32 of
introducer needle 31 from being moved distally out of needle shield
40 after sharp distal tip 32 has been withdrawn proximally into
needle shield 40. Where enlarged diameter portion 38 is
symmetrically disposed about the shaft of introducer needle 31,
preferably the diameter of enlarged diameter portion 38 should be
about 0.004 inches greater than the diameter of the main portion of
introducer needle 31. To ensure this difference in diameter is
achieved, that portion of introducer needle 31 immediately distal
to distal portion 38b can be formed with a slightly increasing
taper from distal portion 38b toward the distal end of introducer
needle 31. See FIG. 3A. Grinding that portion of introducer needle
31 can form this taper immediately distal of distal portion
38b.
[0153] The lock that prevents unwanted distal movement of sharp
distal tip 32 of introducer needle 31 out of the distal end of
needle shield 40 once sharp distal tip 32 has been proximally
withdrawn into needle shield 40 can take many forms. As used herein
the phrase "unwanted distal movement of introducer needle 31" means
distal movement of introducer needle 31, during normal use of
catheter and introducer needle assembly and under normal
circumstances, such that sharp distal tip 32 is not re-exposed from
distal opening 45 of needle shield 40 after the lock engages
introducer needle 31.
[0154] As shown in FIGS. 4 through 7, the lock can be in the form
of a spring gate 100, which can include a separate biasing
mechanism 150, to lock introducer needle 31 in place in needle
shield 40. In this embodiment for the lock, the discontinuous
portion is preferably an enlarged diameter portion 38.
[0155] Spring gate 100 and biasing mechanism 150 are located in
cavity 42 of housing 41 of needle shield 40 and about introducer
needle 31. Spring gate 100 has a pair of spaced apart tines 110
connected by a base 120. Tines 110 should define at least one
portion having a distance therebetween that is slightly larger than
the diameter of the main portion of introducer needle 31 and is
less than the diameter of enlarged diameter portion 38. This allows
the main portion of introducer needle 31 to be positioned between
tines 110 and move proximally past tines 110. Base 120 may extend
generally perpendicular to tines 110 to provide more surface area
to contact biasing mechanism 150, described below. Although the
face of spring gate 100 is shown in the FIGS. as having a generally
U-shape, it is to be understood that other shapes could be used for
the face of spring gate 100 as long as the shape allows at least
one tine 110 to engage enlarged diameter portion 38. For example,
the face of spring gate 100 could have a V-shape or an L-shape.
[0156] Biasing mechanism 150 forces spring gate 100 up into contact
with introducer needle 31 and ensures that tines 110 and base 120
remain adjacent to introducer needle 31. Biasing mechanism 150 may
take any appropriate form. For example, it may be a helical spring
as shown in FIGS. 4 through 6, or it may be a compressible
rubber-like material that acts as a spring or it may be configured
as a leaf spring. Moreover, biasing mechanism 150 and tines 110
could be integrated as one member.
[0157] As introducer needle 31 is withdrawn proximally into needle
shield 40, the main portion of introducer needle 31 passes between
tines 110. When enlarged diameter portion 38 abuts tines 110,
spring gate 110 is rotated proximally and forced downwardly against
the bias of biasing mechanism 150 by the proximal movement of
enlarged diameter portion 38. This allows enlarged diameter portion
38 to pass proximally past tines 110. Compare FIGS. 4 and 5. Once
enlarged diameter portion 38 is proximal of tines 110, biasing
mechanism 150 forces spring gate 100 to rotate clockwise, as seen
in the FIGS, back into engagement with introducer needle 31. When
enlarged diameter portion 38 is proximal of tines 110, sharp distal
tip 32 is proximal of distal opening 45. See FIG. 6. Similarly, all
of the embodiments disclosed herein are configured such that sharp
distal tip 32 is locked in needle shield 40 proximal of distal
opening 45.
[0158] Subsequent distal movement of introducer needle 31 is
prevented by the engagement of enlarged diameter portion 38 and
tines 110. Since tines 110 engage the distal wall of cavity 42,
tines 110 cannot be moved distally past this distal wall. Thus, if
a clinician tries to advance introducer needle 31 distally after
enlarged diameter portion 38 has been moved proximal of tines 110,
enlarged diameter portion 38 would butt up against tines 110 which
in turn would butt up against the distal wall of cavity 42. Biasing
mechanism 150 ensures that tines 110 remain engaged to introducer
needle 31. And as discussed above, further proximal movement of
introducer needle 31 from needle shield 40 is prevented because
enlarged diameter portion 38 blocks further proximal movement of
introducer needle 31 through proximal opening 43 or washer 49.
Alternatively, a tether 50 connecting needle shield 40 and needle
hub 34 could be used to prevent unwanted proximal movement of
introducer needle 31 out of needle shield 40.
[0159] A second embodiment for the lock that prevents unwanted
distal movement of introducer needle 31 is a leaf spring 200. See
FIGS. 8 through 10. Leaf spring 200 has a proximal wall 210
defining an opening 215 therein aligned with proximal opening 43 of
cavity 42. Proximal wall 210 is generally perpendicular to the
longitudinal axis of introducer needle 31. Where enlarged diameter
portion 38 is used on introducer needle 31, preferably opening 215
has a diameter at least slightly larger than the diameter of the
main portion of introducer needle 31 but smaller than the diameter
of enlarged diameter portion 38. Of course, it is not necessary for
leaf spring 200 to include proximal wall 210 and opening 215 as
long as proximal opening 43, washer 49 or tether 50 is used to
prevent proximal movement of sharp distal tip 32 out of needle
shield 40.
[0160] Leaf spring 200 also has a support leg 220 and a locking leg
230 oriented at an angle to support leg 220 such that locking leg
230 is directed generally toward proximal wall 210 so that locking
leg 230 is preferably not perpendicular to support leg 220.
Preferably, locking leg 230 approaches being parallel to support
leg 220. As seen in FIGS. 8-10 support leg 220 and locking leg 230
are preferably oriented to each other such that leaf spring 200 has
a generally V-shape lying on its side, with the apex of the V
facing distally. This V-shaped configuration ensures that locking
leg 230 is biased toward introducer needle 31 and is oriented at an
angle to support leg 220.
[0161] Locking leg 230 includes a pair of spaced apart tines 240.
Along at least one portion of tines 240, a distance is defined
therebetween that is slightly larger than the diameter of the main
portion of introducer needle 31 and is less than the diameter of
enlarged diameter portion 38. This allows the main portion of
introducer needle 31 to extend between tines 240 and move
proximally past tines 240. Tines 240 are preferably oriented on
locking leg 230 so as to assume a generally V-shaped
configuration.
[0162] As introducer needle 31 is withdrawn proximally into needle
shield 40, the main portion of introducer needle 31 passes between
tines 240. When enlarged diameter portion 38 abuts tines 240, they
are rotated counterclockwise, as seen in the FIGS. This allows
enlarged diameter portion 38 to move proximally past tines 240.
Once enlarged diameter portion 38 is proximal of tines 240, the
bias of leaf spring 200 causes locking leg 230 and tines 240 to
rotate clockwise, as seen in the FIGS. back into engagement with
introducer needle 31. If introducer needle 31 is subsequently moved
distally, locking leg 230 and tines 240 will continue to rotate
clockwise, as seen in the FIGS. This forces introducer needle 31
upwardly into tight engagement with the walls defining cavity 42 of
needle shield 40 and prevents re-exposure of sharp distal tip 32.
Any subsequent distal movement of introducer needle 31 is prevented
and, if enough distally directed force is applied to introducer
needle 31, could cause introducer needle 31 to buckle and
permanently lock introducer needle 31 in needle shield 40. See FIG.
9.
[0163] Further proximal movement of introducer needle 31 is
prevented by the engagement of enlarged diameter portion 38 with
proximal wall 210. Again, if desired, a tether 50 connecting needle
shield 40 to needle hub 34 could be used to prevent this unwanted
proximal movement of introducer needle 31 with respect to needle
shield 40.
[0164] A third embodiment for the lock that prevents unwanted
distal movement of introducer needle 31 is a leaf spring 300. See
FIGS. 11 through 13. Leaf spring 300 has a proximal wall 310
defining an opening 315 therein aligned with proximal opening 43 of
cavity 42. Proximal wall 310 is generally perpendicular to the
longitudinal axis of needle shield 40. Where enlarged diameter
portion 38 is used on introducer needle 31, preferably the diameter
of opening 315 is slightly larger than the diameter of the main
portion of introducer needle 31 but smaller than the diameter of
enlarged diameter portion 38. Of course, it is not necessary for
leaf spring 300 to include proximal wall 310 and opening 315 as
long as proximal opening 43, washer 49 or tether 50 is used to
prevent proximal movement of sharp distal tip 32 out of needle
shield 40.
[0165] Leaf spring 300 also has a support leg 320 and a locking leg
330 oriented at an angle to support leg 320 such that locking leg
330 is directed generally toward proximal wall 310 and is not
perpendicular to support leg 320. Preferably, locking leg 330
approaches being parallel to support leg 320. As seen in FIG. 11,
support leg 320 and locking leg 330 are preferably oriented to each
other such that leaf spring 300 has a generally V-shape lying on
its side, with the apex of the V facing distally. This V-shaped
configuration ensures that locking leg 330 is biased toward
introducer needle 31. Alternatively locking leg 330 could be
oriented at a different angle to support leg 320. For example,
locking leg 330 could be oriented at an angle to support leg 320
that approaches 90 degrees. See FIG. 17 and compare support leg 620
and locking leg 630. Indeed, locking leg 330 could in fact be
perpendicular to support leg 320 or could be oriented anywhere
between being parallel to or perpendicular to support leg 320. The
main criterion for the configuration of leaf spring 300 is to have
locking leg 330 biased toward introducer needle 31 so it engages
enlarged diameter portion 38.
[0166] That portion of locking leg 330 that abuts introducer needle
31 can be contoured to form a generally semi-circular cross-section
to approximate a portion of the circumference of the main portion
of introducer needle 31. This minimizes drag on introducer needle
31 as it is being moved proximally past locking leg 330.
[0167] In the embodiment of FIGS. 11 through 13, enlarged diameter
portion 38 shown in FIG. 3A is preferably used. This embodiment
includes a tapered proximal portion 38a and a distal portion 38b
that is generally perpendicular to the longitudinal axis of
introducer needle 31. However, it is to be understood that the
other embodiments for the discontinuous portion on introducer
needle 31 could be used. In addition, the end of locking leg 330
that engages the discontinuous portion could be configured
appropriately to mechanically engage the discontinuous portion. For
example, if notch 39 were used as the discontinuous portion, the
portion of locking leg 330 that engages notch 39 would include a
tab to engage the notch. See for example, the tab in FIG. 31.
[0168] Locking leg 330 rides along the main portion of introducer
needle 31 as introducer needle 31 is withdrawn proximally into
needle shield 40. Locking leg 330 also rides over enlarged diameter
portion 38 as it is pulled proximally past locking leg 330. Having
a tapered proximal portion 38a facilitates movement of enlarged
diameter portion 38 past locking leg 330 so enlarged diameter
portion 38 is proximal of locking leg 330. If introducer needle 31
is moved distally after enlarged diameter portion 38 and distal
portion 38b are moved proximally of the proximal end of locking leg
330, the proximal end of locking leg 330 will engage distal portion
38b and prevent further distal movement of introducer needle 31. In
addition, such distally directed force applied to introducer needle
31 will cause locking leg 330 to rotate clockwise, as seen in the
FIGS. This forces introducer needle 31 upwardly into tight
engagement with the walls defining cavity 42 of needle shield 40
and prevents re-exposure of sharp distal tip 32.
[0169] Further proximal movement of introducer needle 31 is
prevented by the engagement of enlarged diameter portion 38 with
proximal wall 310. Again, if desired, a tether 50 connecting needle
shield 40 to needle hub 34 could be used to prevent this unwanted
proximal movement of introducer needle 31 with respect to needle
shield 40.
[0170] A fourth embodiment for the lock that prevents unwanted
distal movement of introducer needle 31 is shown in FIGS. 14 and
15. The fourth embodiment is a leaf spring 400 that includes a
proximal wall 410 supporting a pair of support legs 420 each of
which is connected to a locking leg 430. Proximal wall 410 defines
an opening 415 therein through which introducer needle 31 can
extend. Proximal wall 410, support legs 420 and locking legs 430
are configured so that locking legs are biased toward the main
portion of introducer needle 31. In this embodiment, introducer
needle 31 preferably includes enlarged diameter portion 38 shown in
FIG. 3A. Although as previously discussed, other embodiments for
the discontinuous portion could also be used.
[0171] Locking legs 430 can be oriented at a wide range of angles
to support legs 420. Preferably locking legs 430 are oriented at an
angle less than 90 degrees to support legs. Regardless of the angle
of orientation, locking legs 430 must engage distal portion 38b in
order to prevent unwanted distal movement of introducer needle
31.
[0172] Locking legs 430 ride along the main portion of introducer
needle 31 as introducer needle 31 is withdrawn proximally into
needle shield 40. Locking legs 430 ride over enlarged diameter
portion 38 as it is pulled proximally past locking legs 430.
Tapered proximal portion 38a facilitates movement of enlarged
diameter portion 38 past locking legs 430 so enlarged diameter
portion is proximal of locking legs 430. If introducer needle 31 is
moved distally after enlarged diameter portion 38 and distal
portion 38b are moved proximally of the proximal end of locking
legs 430, the ends of locking legs 430 will engage distal portion
38b and prevent further distal movement of introducer needle
31.
[0173] Further proximal movement of introducer needle 31 is
prevented by the engagement of enlarged diameter portion 38 with
proximal wall 410. Again, if desired, a tether 50 connecting needle
shield 40 to needle hub 34 could be used to prevent this unwanted
proximal movement of introducer needle 31 with respect to needle
shield 40.
[0174] As shown in FIGS. 14 and 15, leaf spring 400 and housing 41
may be configured to enhance the mechanical engagement between
locking legs 430 and enlarged diameter portion 38. This is achieved
by allowing leaf spring 400 to move distally in cavity 42 after
enlarged diameter portion 38 has been withdrawn into needle shield
40 proximal of locking legs 430. In this embodiment, cavity 42 has
a tapered cross section. This taper is such that the inner diameter
of cavity 42 decreases from its proximal portion toward its distal
portion. This taper should be sufficient to engage support legs 420
and force support legs 420 toward introducer needle 31. Preferably
this taper, as defined by the angle between the wall of cavity 42
and the longitudinal axis of introducer needle 31, should be less
than 90 degrees minus the static slip angle created between the
surface of support legs 420 and the wall of cavity 42. With this
configuration, any subsequent distal movement of introducer needle
31 will cause leaf spring 400 to move distally with introducer
needle 31 until support legs 420 engage the tapered walls of
housing 41. As support legs 420 engage the tapered walls, locking
legs 430 are forced into tighter contact with the shaft of
introducer needle 31 and may even bind into the surface of
introducer needle 31. This tight contact between locking legs 430
and distal portion 38b ensures that the force needed to overcome
the mechanical engagement between the ends of locking legs 430 and
distal portion 38b will be too high for a clinician, using catheter
and introducer needle assembly 10 in a normal manner and in normal
circumstances, to overcome.
[0175] The fifth embodiment of the lock that prevents unwanted
distal movement of introducer needle 31 is a variation of the
fourth embodiment of the lock that prevents unwanted distal
movement of introducer needle 31 and that minimizes drag on
introducer needle 31 as it is being withdrawn in needle shield 40.
See FIG. 16. The fifth embodiment is a leaf spring 500 that
includes a proximal wall 510 supporting a pair of support legs 520
each of which is connected to a locking leg 530. Proximal wall 510
defines an opening 515 therein through which introducer needle 31
can extend. Proximal wall 510, support legs 520 and locking legs
530 are configured so that locking legs are biased toward the shaft
of introducer needle 31. In this embodiment, introducer needle 31
preferably includes enlarged diameter portion 38 shown in FIG. 3A.
Although as previously discussed, other embodiments for the
discontinuous portion could also be used.
[0176] At least one, but preferably each support leg 520 includes a
support finger 550 thereon. Each support finger 550 cooperates with
a support tab 560 formed on housing 41 to hold each support leg 520
away from the shaft of introducer needle 31. Leaf spring 500 is
disposed in cavity 42 such that proximal wall 510 is spaced
distally from the proximal wall of cavity 42 to allow proximal
movement of leaf spring 500 when introducer needle 31 is withdrawn
into needle shield 40. When enlarged diameter portion 38 engages
proximal wall 510 as a result of the proximal movement of
introducer needle 31, leaf spring 500 will be moved proximally with
continued proximal movement of introducer needle 31. This allows
each support finger 550 to be moved out of engagement with support
tabs 560, which in turn allows support legs 520 to return to their
inward position. In the inward position, locking legs 530 engage
the main portion of introducer needle 31. Unwanted distal and
proximal movement of introducer needle 31 is prevented in a similar
manner as is accomplished in the fourth embodiment of the lock.
[0177] The sixth embodiment of the lock that prevents unwanted
distal movement of introducer needle 31 is shown in FIGS. 17 and
18. In this embodiment, the leaf spring 600 includes a proximal
wall 610 supporting a pair of support legs 620 each of which is
connected to a locking leg 630. Proximal wall 610 defines an
opening 615 therein through which introducer needle 31 can extend.
In this embodiment, it is not necessary that locking legs 630 be
biased toward the shaft of introducer needle 31. In fact, in order
to minimize drag on the shaft of introducer needle 31 as it is
moved proximally into needle shield 40, the ends of locking legs
630 are preferably spaced away from the shaft of introducer needle
31. This allows introducer needle 31 to be easily withdrawn into
needle shield 40.
[0178] In this embodiment, introducer needle 31 preferably includes
enlarged diameter portion 38 shown in FIG. 3A. Although as
previously discussed, other embodiments for the discontinuous
portion could also be used.
[0179] Cavity 42 has a proximal portion and a distal portion where
the diameter of the proximal portion is smaller than the diameter
of the distal portion. When sharp distal tip 32 is distal of the
distal end of needle shield 40 prior to use in inserting a catheter
into a patient, leaf spring 600 is located substantially in the
distal portion of cavity 42. As introducer needle 31 continues to
be moved proximally into needle shield 40, enlarged diameter
portion 38 moves proximally of locking legs 630 and subsequently
engages proximal wall 610 and subsequently pulls leaf spring 600
into the proximal portion of cavity 42. The smaller diameter for
the proximal portion forces support legs 620 and thus locking legs
630 toward the main portion of introducer needle 31 so that locking
legs 630 can engage introducer needle 31 distal of but adjacent to
enlarged diameter portion 38.
[0180] The leaf spring 600 includes at least one, and preferably
two, flexible radially outwardly biased fingers 650 extending from
support legs 620. Housing 41 defines a slot 660 for each finger 650
wherein each slot 660 has a proximally facing shoulder. As leaf
spring 600 is pulled proximally into the proximal portion of cavity
42 by the engagement between enlarged diameter portion 38 and
proximal wall 610, fingers 650 flex inwardly because of their
contact with the inner walls of housing 41. However, once fingers
650 become aligned with slots 660, fingers 650 can return to their
outward position and move into slots 660. The engagement of fingers
650 and the proximally facing shoulder of slot 660 prevents any
subsequent distal movement of leaf spring 600 with respect to
housing 41. When leaf spring 600 is in this position in housing 41,
the ends of locking legs 630 abut introducer needle 31 distal of
but adjacent to enlarged diameter portion 38. Thus, any unwanted
distal movement of introducer needle 31 is prevented by the
engagement of the ends of locking legs 630 and distal portion
38b.
[0181] A seventh embodiment for the lock that prevents unwanted
distal movement of introducer needle 31 is shown in FIGS. 19
through 21. In this embodiment, leaf spring 700 includes a proximal
wall 710 supporting a support leg 720, which in turn is connected
to a locking leg 730. Proximal wall 710 defines an opening 715
therein through which introducer needle 31 can extend. Preferably
locking leg 730 is substantially perpendicular to support leg 720
and defines an opening 735 therein. Preferably the diameter of
opening 735 is slightly larger than the diameter of the main
portion of introducer needle 31 but is smaller than the diameter of
enlarged diameter portion 38. Proximal wall 710, support leg 720
and locking leg 730 are configured such that locking leg 730 is
biased toward introducer needle 31. Of course, the orientation of
leaf spring 700 could be at any angle around the longitudinal axis
of introducer needle 31 so that support leg is biased toward
introducer needle 31.
[0182] In this embodiment, introducer needle 31 must include
enlarged diameter portion 38. Preferably, enlarged diameter portion
38 shown in FIG. 3C is used.
[0183] In the unlocked and biased position for leaf spring 700,
sharp distal tip 32 of introducer needle 31 is distal of the distal
end of needle shield 40 and locking leg 730 contacts and is biased
toward introducer needle 31. See FIG. 19. As introducer needle 31
is withdrawn proximally into needle shield 40 locking leg 730 rides
over the surface of introducer needle 31. Locking leg 730 can
include a proximally or distally directed tab 738 that contacts
introducer needle 31 to minimize drag on introducer needle 31. Once
sharp distal tip 32 of introducer needle 31 is moved proximal of
locking leg 730, leaf spring 700 returns to its unbiased, i.e.
activated, position such that opening 735 is substantially aligned
with the longitudinal axis of introducer needle 31 and distal
opening 45. If introducer needle 31 is thereafter moved distally
with respect to needle shield 40, sharp distal tip 32 of introducer
needle 31 extends through opening 735 until enlarged diameter
portion 38 engages opening 735. Unwanted distal movement of
introducer needle 31 is thus prevented so that sharp distal tip 32
cannot be re-exposed outside needle shield 40.
[0184] Further proximal movement of introducer needle 31 is
prevented by the engagement of enlarged diameter portion 38 with
proximal wall 710. Again, it is not necessary for leaf spring 700
to include proximal wall 710 and opening 715. As long as proximal
opening 43, washer 49 or tether 50 could be used instead to prevent
this unwanted proximal movement of introducer needle 31 with
respect to needle shield 40.
[0185] Locking leg 730 can have a funnel configuration 736 adjacent
to opening 735. This funnel configuration 736 acts as a guide for
introducer needle 31 to ensure that it passes through opening 735
if introducer needle 31 is moved distally after it has been
withdrawn into needle shield 40. Funnel configuration 736 can be
configured so that it is complementary to the shape of the tapered
distal portion 38b of enlarged diameter portion 38 shown in FIG.
3C.
[0186] An eighth embodiment of the lock that prevents unwanted
distal movement of introducer needle 31 is shown in FIGS. 22
through 25. In this embodiment, introducer needle 31 must include
enlarged diameter portion 38. Preferably, enlarged diameter portion
38 shown in FIG. 3C is used.
[0187] The lock of this embodiment is a leaf spring 800 that
includes a proximal wall 810, a support leg 820 connected to one
end of proximal wall 810 and a locking leg 830 connected to support
leg 820. In addition, leaf spring 800 includes an outwardly biased
locking arm 850 connected to the other end of proximal wall 810. An
opening 815 is defined in proximal wall 810 and an opening 835 is
defined in locking leg 830. Both openings 815 and 835 allow
introducer needle 31 to extend therethrough. Opening 835 has a
diameter slightly larger than the diameter of enlarged diameter
portion 38, whereas opening 815 has a diameter smaller than the
largest diameter of enlarged diameter portion 38.
[0188] Cavity 42 of housing 41 defines a proximal portion, a medial
portion and a distal portion wherein the diameter of the medial
portion is less than the diameters of the proximal portion and the
distal portion. As a result of this configuration, cavity 42
defines a proximally facing shoulder 860 and a distally facing
shoulder 870. Leaf spring 800 is initially located in the medial
portion of cavity 42 such that locking leg 830 abuts distally
facing shoulder 870. In addition, leaf spring 800 is located in the
medial portion of cavity 42 such that it is movable proximally with
respect to housing 41.
[0189] Prior to withdrawal of sharp distal tip 32 into needle
shield 40, leaf spring 800 is in the position shown in FIG. 22 such
that locking leg 830 is generally perpendicular to the shaft of
introducer needle 31. As introducer needle 31 is moved proximally
into needle shield 40, enlarged diameter portion 38 passes through
opening 835 of locking leg 830 until the proximal end of enlarged
diameter portion 38 engages proximal wall 810. Since the diameter
of opening 815 is less than the largest diameter of enlarged
diameter portion 38, continued relative proximal movement of
introducer needle 31 with respect to leaf spring 800 is prevented.
However, continued proximal movement of introducer needle 31 causes
leaf spring 800 to move proximally until proximal wall 810 abuts
against the proximal wall of cavity 42. At this point, further
proximal movement of introducer needle 31 and leaf spring 800 is
prevented.
[0190] Since locking leg 830 abuts distally facing shoulder 870 in
housing 41, the proximal movement of leaf spring 800 with respect
to housing 41 causes locking leg 830 to rotate. As such the
orientation of locking leg 830 with respect to introducer needle 31
changes so locking leg 830 is no longer perpendicular to introducer
needle 31. Compare FIGS. 22 and 23. In addition, the proximal
movement of leaf spring 800 causes locking arm 850 to become
aligned with the larger diameter proximal portion of cavity 42.
This allows locking arm 850 to move to its outward position, away
from introducer needle 31 into the proximal portion of cavity 42 so
that locking arm 850 abuts proximally facing shoulder 860. In this
position, any subsequent distal movement of leaf spring 800 with
respect to housing 41 is prevented.
[0191] When locking leg 830 is no longer perpendicular to
introducer needle 31, opening 835 is skewed with respect to
enlarged diameter portion 38. Thus, in this orientation, the
effective diameter of opening 835 is less than the diameter of
enlarged diameter portion 38 and is approximately equal to the
diameter of the main portion of introducer needle 31. As used
herein, the term "effective diameter" means the diameter of the
image of opening 835 when it is projected onto a plane
perpendicular to the longitudinal axis of introducer needle 31.
Because, the effective diameter of opening 835 is less than the
diameter of enlarged diameter portion 38 in the orientation shown
in FIGS. 23 and 25, enlarged diameter portion 38 is prevented from
moving distally past locking leg 830 and sharp distal tip 32 is
effectively locked in needle shield 40. Indeed, as introducer
needle 31 is moved distally, the binding force between locking leg
830 and introducer needle 31 increases making it extremely
difficult for enlarged diameter portion 38 to be moved distally
past locking leg 830 and thus defeat this lock.
[0192] A ninth embodiment of the lock that prevents unwanted distal
movement of introducer needle 31 is shown in FIGS. 26 through 28
and is a tube 900. In this embodiment, the discontinuous portion on
introducer needle 31 is preferably an enlarged diameter portion.
Even more preferably, enlarged diameter portion 38 shown in FIG. 3A
is used although other embodiments for enlarged diameter portion 38
could be used.
[0193] Tube 900 is located in cavity 42 and includes at least one
movable lanced tab 950 that extends inwardly into tube 900 in a
proximal direction. Preferably two such tabs 950 are formed on
opposite sides of tube 900. The distal portion of tube 900 has an
inner diameter greater than the diameter of enlarged diameter
portion 38 to allow introducer needle 31 freely to move therein.
Because tabs 950 are movable, enlarged diameter portion 38 can move
past the proximal ends of tabs 950 as introducer needle 31 is
withdrawn proximally into needle shield 40. Again the proximal
movement of introducer needle 31 past tabs 950 is facilitated by
tapered proximal portion 38a. Once introducer needle 31 has been
withdrawn proximally into needle shield 40 such that tabs 950 are
distal of distal portion 38b, any unwanted distal movement of
introducer needle 31 will be prevented by the engagement of the
proximal ends of tabs 950 with enlarged diameter portion 38.
Further proximal movement of introducer needle 31 is prevented by
the engagement of enlarged diameter portion 38 with proximal
opening 43. Alternatively, the proximal portion of tube 900 could
be formed with an inner diameter smaller than the diameter of
enlarged diameter portion 38 to prevent unwanted proximal movement
of introducer needle out of tube 900. In addition, washer 49 or
tether 50 could be used to prevent unwanted proximal movement.
[0194] A tenth embodiment of the lock that prevents unwanted
movement of introducer needle 31 is shown in FIGS. 29 through 32.
This lock is a speed nut 1000, which defines a through hole 1010
that has a diameter slightly larger than the diameter of the main
portion of introducer needle 31. This allows introducer needle 31
to extend through speed nut 1000. Speed nut 1000 includes at least
one but preferably a plurality of movable tabs 1020 extending from
the main body portion 1030 of speed nut 1000. Tabs 1020 are biased
toward introducer needle 31 so they are proximally oriented and
extend inwardly toward the proximal end of introducer needle 31.
The distal ends of tabs 1020 are connected to main body portion
1030 of speed nut 1000 by, for example, a living hinge. See FIG.
32.
[0195] Because tabs 1020 are proximally oriented and movable,
enlarged diameter portion 38 can move easily past the proximal ends
of tabs 1020 as introducer needle 31 is withdrawn proximally into
needle shield 40. Once introducer needle 31 has been withdrawn
proximally into needle shield 40 such that tabs 1020 are distal of
enlarged diameter portion 38, unwanted distal movement of
introducer needle 31 will be prevented by the engagement of the
proximal ends of tabs 1020 with distal portion 38b of enlarged
diameter portion 38. The generally proximal orientation of tabs
1020 also causes tabs 1020 to bite into the surface of introducer
needle 31 to hold introducer needle 31 in place. Further proximal
movement of introducer needle 31 is prevented by the engagement of
enlarged diameter portion 38 with proximal opening 43 or washer 49.
Again, proximal opening 43, washer 49 or tether 50 could be used to
prevent this unwanted proximal movement.
[0196] As shown in FIG. 31, the discontinuous portion of introducer
needle 31 can be in the form of a notch 39 such as shown in FIGS.
3E, 3F and 3G. When introducer needle 31, and thus notch 39, is
withdrawn through speed nut 1000, at least one tab 1020 will drop
into notch 39. Any subsequent distal movement of introducer needle
31 will be prevented by the engagement of tab 1020 with the
distally facing portion, i.e. the proximal edge, of notch 39. The
use of a plurality of tabs 1020 formed around main body portion
1030 ensures that at least one tab 1020 will engage notch 39.
Alternatively, a plurality of longitudinally displace notches 39
located about the circumference of introducer needle 31 could be
used to catch tabs 1020.
[0197] When a notch 39 is used as the discontinuous portion on
introducer needle 31, such as shown in FIG. 3D, instead of an
enlarged diameter portion 38, a tether 50 connecting needle shield
40 to needle hub 34 may be used to prevent unwanted proximal
movement of introducer needle 31 with respect to needle shield 40.
Also, as described herein, tether 50 is a mechanism to prevent
introducer needle 31 from being withdrawn proximally out of the
proximal portion of needle shield 40 instead of the engagement of
enlarged diameter portion 38 with proximal opening 43 or washer
49.
[0198] An eleventh embodiment of the lock that prevents unwanted
distal movement of introducer needle 31 is shown in FIGS. 33
through 35, 37A, 37B and 37C. In this embodiment, the lock is a
retention plate 1100, which includes tabs 1120 that do not extend
proximally from the main portion of retention plate 1100. See
specifically FIG. 37A. However, tabs 1120 are still connected to
the main portion of retention plate 1100 via any appropriate
mechanism, such as a living hinge, so that tabs 1120 are movable
with respect to the main portion of retention plate 1100. Tabs 1120
define a through hole 1130 between the ends of each tab 1120 that
has a diameter slightly greater than the diameter of the main
portion of introducer needle 31 but is smaller than the diameter of
enlarged diameter portion 38. Retention plate 1100 is located
adjacent to the proximal face of a medial wall 1140 formed in
cavity 42 of housing 41. Medial wall 1140 defines an opening 1145
therethrough that has a diameter greater than the diameter of
enlarged diameter portion 38.
[0199] As introducer needle 31 is moved proximally into needle
shield 40, enlarged diameter portion 38 can pass through opening
1145. In addition, enlarged diameter portion 38 can move past tabs
1120 since tabs 1120 will move proximally out of the way of
enlarged diameter portion 38. However, once enlarged diameter
portion 38 is moved proximal of retention plate 1100, any
subsequent distal movement of introducer needle 31 with respect to
needle shield 40 is prevented. This is because enlarged diameter
portion 38 cannot extend back through hole 1130 but instead engages
the surface of tabs 1120 adjacent to hole 1130. In addition, tabs
1120 cannot move distally out of the way of enlarged diameter
portion 38 because medial wall 1140 prevents any such distal
movement of tabs 1120. Any further proximal movement of introducer
needle 31 is prevented by proximal opening 43, washer 49 or tether
50.
[0200] FIGS. 37B and 37C show variations of the retention plate
shown in FIG. 37A. In both of these variations, tabs 1120 include
distally extending fingers adjacent to hole 1130 such as to define
the diameter of hole 1130. Fingers 1101 are shown in FIG. 37B and
fingers 1101' are shown in FIG. 37C. In FIG. 37C, the outer
portions of fingers 1101' are tapered so they slope toward
introducer needle 31 in the distal direction and the inner walls
defining opening 1145 have a complementary slope. Fingers 1101 and
1101' fill any excess space in opening 1145 in medial wall 1140 and
ensure that unwanted distal movement of introducer needle 31. In
the case of the variation shown in FIG. 37C, fingers 1101' provide
a greater holding force to introducer needle 31 to prevent unwanted
distal movement of introducer needle 31. This is because as
introducer needle 31 is moved distally after enlarged diameter
portion 38 has been moved proximal of retention plate 1100, fingers
1101' will wedge into opening 1145 making it significantly more
difficult to move introducer needle 31 distally.
[0201] FIGS. 33 through 36C, 38 and 39 show a first embodiment of a
resilient spring clip 1201 that is used to connect needle shield 40
to catheter hub 24 until sharp distal tip 32 of introducer needle
31 has been withdrawn into needle shield 40. A spring arm 151 that
is formed in a V-shaped configuration defines the spring clip.
Spring arm 151 is disposed in housing 41 such that the apex of the
V is pointed up toward the top of housing 41 and the legs defining
the V straddle the longitudinal axis of introducer needle 31 when
spring arm 151 is in its unbiased position. In this orientation,
spring arm 151 is adapted for motion transverse to the longitudinal
axis of introducer needle 31. This motion is along a defined path
provided by a ramped surface 159 in housing 41. See FIGS. 38 and
39.
[0202] Of course spring arm 151 could be disposed in housing 41
such that the apex is oriented in other positions on a circle
concentric to the longitudinal axis of introducer needle 31. All
that is required is that spring arm 151 be adapted for motion
transverse to the longitudinal axis of introducer needle 31. The
apex of the V shape facilitates the flexing of spring arm 151 to
and from a biased condition. In addition, the apex of the V shape
could be in the form of a living hinge.
[0203] When sharp distal tip 32 of introducer needle 31 is distal
of needle shield 40, introducer needle 31 abuts spring arm 151 so
as to hold spring arm 151 in the biased, unactivated, clipped
position. Spring arm 151 includes a clip arm 152 which extends
generally parallel to the longitudinal axis of introducer needle
31. Clip arm 152 preferably has a finger 153 formed thereon, which
is adapted to engage thread 44 or a corresponding detent 26 formed
on catheter hub 24 when spring arm 151 is in the clipped position.
Detent 26 can be the flange or luer locking ears 44 shown on the
proximal end of catheter hub 24. Alternatively, detent 26 can take
the form of a notch or slot, or an upstanding peg. Although the use
of finger 153 and detent 26 is preferred because it provides
positive mechanical engagement therebetween, these elements are not
necessary. Without any detents the engagement force between clip
arm 152 and catheter hub 24 is limited to frictional force which
may be easier to overcome than with mechanical engagement. However,
in certain situations, this frictional force may be sufficient.
[0204] When sharp distal tip 32 of introducer needle 31 is moved
proximally into needle shield 40 so that introducer needle 31 no
longer abuts spring arm 151, spring arm 151 can flex to its
unbiased, activated non-clipped position out of engagement with
catheter hub 24. This allows catheter hub 24 to be disconnected
from needle shield 40. Spring arm 151 may include a longitudinally
extending flag 158 that minimizes drag on introducer needle 31, and
enlarged diameter portion 38 if any, as introducer needle 31 is
being moved proximally into needle shield 40. In addition, spring
arm 151 may include an arm 53 extending therefrom and which defines
an opening therein. In one embodiment, arm 53 also includes a
longitudinally extending guide rail 51 that guides introducer
needle 31 toward opening 52. See FIG. 36B. The diameter of opening
52 is slightly greater than the diameter of the main portion of
introducer needle 31 but is smaller than the diameter of enlarged
diameter portion 38. Thus spring clip 151 can work to prevent
unwanted distal movement of introducer needle 31 in a similar
manner to the leaf spring 700 shown in FIGS. 19-21. In an
alternative embodiment, a tapered opening 54 can be used instead.
See FIG. 36. All that is required is for opening 54 to define a
portion that allows the main portion of introducer needle 31 to
extend therethrough and to define a portion that does not allow the
enlarged diameter portion 38 to extend therethrough.
[0205] It is to be understood that the various embodiments of the
resilient spring clips discussed hereinafter can be used in
conjunction with any of the previous embodiments of the lock that
prevents unwanted distal movement of sharp distal tip 32 of
introducer needle 31 out of the distal end of needle shield 40 once
sharp distal tip 32 has been proximally withdrawn into needle
shield 40. Preferably, the resilient spring clips are formed from
stainless steel. However, it is to be understood that other
flexible, strong materials could also be used to form the resilient
spring clips.
[0206] As previously mentioned, the V-shaped configuration of
spring arm 151 ensures that it can flex between a clipped, i.e. a
biased and an unactivated, position and a non-clipped, i.e. an
unbiased and an activated, position. In the unactivated position,
finger 153 is positioned into engagement with catheter hub 24. See
FIG. 34. In the activated position, finger 153 is not in engagement
with catheter hub 24. See FIG. 35. Preferably, housing 41 defines a
ramp 159 extending transversely to the longitudinal axis of
introducer needle 31. See FIGS. 38 and 39. Ramp 159 is located in
housing 41 such that it engages clip arm 152. Ramp 159 acts as a
guide for clip arm 152 to ensure clip arm 152 and finger 153 do not
rotate around catheter hub 24 but instead move transversely to the
longitudinal axis of introducer needle 31 once sharp distal tip 31
is withdrawn proximally of spring arm 151 out of engagement with
catheter hub 24.
[0207] Although this V-shaped configuration for spring clip 1201 is
preferred, many different configurations may be used. All that is
required is that the orientation allows spring arm 151 to flex so
clip arm 152 and finger 153 can be moved into engagement with
catheter hub 24 and can move to an activated position out of
engagement with catheter hub 24.
[0208] A first embodiment of a spring clip 1211 with a transverse
barrier can be seen in FIGS. 40 and 41. Spring clip 1211 is formed
from spring arm 191 and clip arm 192. In this embodiment, spring
arm 191 is a resilient, substantially straight and unbent member.
Clip arm 192 defines a hole 195 through which introducer needle 31
extends. Spring arm 191 is oriented generally perpendicular to
introducer needle 31 such that the ends of spring arm 191 are fixed
to housing 41. Thus, in the unbiased, i.e. activated non-clipped
position, hole 195 is not longitudinally aligned with introducer
needle 31. See FIG. 41. Although the FIGS. show introducer needle
31 above spring arm 191, it is to be understood that introducer
needle 31 could be below spring arm 191 and spring arm 191 could be
located within housing 41 such that it extends across the diameter,
in any orientation, of a circle concentric to the longitudinal axis
of introducer needle 31.
[0209] When introducer needle 31 extends through hole 195 and past
the distal end of needle shield 40 and into catheter hub 24, spring
arm 191 abuts introducer needle 31 and is prevented from moving out
of engagement with catheter hub 24. See FIG. 40. Clip arm 192
preferably extends perpendicular to spring arm 191 and includes a
finger 193 formed thereon. In addition, catheter hub 24 also
includes a detent 26 thereon for engagement with finger 193. As
discussed above, detent 26 can be a flange or luer locking ears on
the proximal end of catheter hub 24. Alternatively, detent 26 can
take the form of a notch or slot, or an upstanding peg. When
introducer needle 31 extends past spring arm 191, finger 193
engages a detent 26 on catheter hub 24 to maximize the retention
force between clip arm 192 and catheter hub 24. Thus, as long as
introducer needle 31 extends distally past spring arm 191, clip arm
192 and detent 26 remain engaged so catheter hub 24 stays connected
with needle shield 40. Once sharp distal tip 32 of introducer
needle 31 is withdrawn proximally past spring arm 191, clip arm 192
returns to its activated, unbiased, non-clipped position so that
finger 193 can move out of engagement with detent 26. This allows
catheter hub 24 to be separated from needle shield 40.
[0210] Spring clip 1211 oft his embodiment also includes a
transverse barrier 196, which extends perpendicular to and below
spring arm 191 to prevent unwanted distal movement of introducer
needle 31. Thus when sharp distal tip 32 is moved proximally past
spring arm 191, transverse barrier 196 acts as a positive barrier
to engage sharp distal tip 32 of introducer needle 31 to prevent
unwanted distal movement of introducer needle 31. With this
embodiment, no discontinuous portion 38 is needed on introducer
needle 31 and a tether 50 may be used to prevent unwanted proximal
movement of introducer needle 31.
[0211] However, if desired, discontinuous portion 38 could be used
on introducer needle to prevent unwanted distal movement of
introducer needle 31. In that case, transverse barrier 196 could be
formed with an opening 199 therein having a diameter smaller than
the diameter of enlarged diameter portion 38. Opening 199 thus
would prevent unwanted distal movement of introducer needle 31
similar to leaf spring 700 shown in FIGS. 19-21. Indeed, all of the
transverse barriers discussed herein could be modified if desired
to include an opening therein that would not allow enlarged
diameter portion 38 to pass therethrough.
[0212] Although the foregoing embodiments of the spring clips
engage the outside of catheter hub 24, it is to be understood that
the spring clips and introducer needle 31 could be arranged such
that the spring clips engage the inside of catheter hub 24. For
example, the spring clips could be arranged with respect to
introducer needle 31 so that introducer needle 31 pushes the
locking arms radially outwardly. Once sharp distal tip 32 of
introducer needle 31 is moved proximally past the spring arms, they
return to their unbiased position and move the locking arms
inwardly toward the longitudinal axis of needle shield 40.
[0213] FIGS. 42 through 45 show a second embodiment of a spring
clip 1212 with a transverse barrier that connects catheter hub 24
to needle shield 40 until sharp distal tip 32 has been locked in
needle shield 40. Spring clip 1212 of this embodiment is
substantially the same as the embodiment for the spring clip shown
in FIGS. 33 through 36C, 38 and 39 except for the addition of
transverse barrier 296. Thus this embodiment of spring clip 1212
functions to connect catheter hub 24 to needle shield 40 until
sharp distal tip 32 has been locked in needle shield 40 in
substantially the same way as the embodiment shown in FIGS. 33
through 36C, 38 and 39.
[0214] When introducer needle 31 extends through needle shield 40
so that sharp distal tip 32 is distal of distal opening 45, spring
arm 291 abuts the shaft of introducer needle 31 and is biased to
move transverse barrier 296 in front of sharp distal tip 32. Once
sharp distal tip 32 is moved proximally past spring arm 291, spring
arm 291 moves to its activated, unbiased, non-clipped position so
that transverse barrier 296 is in front of sharp distal tip 32.
This prevents any unwanted distal movement of introducer needle
31.
[0215] Where transverse barrier 296 is used, preferably a tether 50
is used to connect needle shield 40 to needle hub 34. Tether 50
prevents unwanted proximal movement of introducer needle 31 with
respect to needle shield 40. Tether 50 can take many different
forms such as a string, a pleated element, a sleeve member
surrounding introducer needle 31 or a plurality of telescoping
members surrounding introducer needle 31. Alternatively, where
transverse barrier 296 is used, unwanted proximal movement of
introducer needle 31 can be prevented in the same manner as the
embodiments previously discussed. As such, introducer needle 31 can
be formed with enlarged diameter portion 38, which would abut
proximal opening 43 or washer 49.
[0216] Where enlarged diameter portion 38 is used on introducer
needle 31, spring clip 1212 could be formed as shown in FIG. 36B or
36C. As discussed above, in those embodiments, the spring clip is
formed with an arm 53 extending therefrom similarly to transverse
barrier 296. However, arm 53 defines an opening 52 or 54 therein.
Opening 54 is tapered from a larger diameter portion to a smaller
diameter portion. In both cases, opening 52 and 54 define a portion
that has a diameter that is smaller than the diameter of enlarged
diameter portion 38. Thus, after spring clip 1212 moves to the
non-clipped position, opening 52 and 54 will be substantially
aligned with introducer needle 31. However, unwanted distal
movement of introducer needle 31 will be prevented because the
smaller diameter portion of opening 52 and 54 will prevent the
passage of enlarged diameter portion 38 therethrough. Similarly,
opening 199 shown in the embodiment of FIG. 45 can cooperate with
enlarged diameter portion 38 to prevent unwanted distal movement of
introducer needle 31.
[0217] A first embodiment of an integrated clip lock 1221 that
connects needle shield 40 to catheter hub 24 and that prevents
unwanted distal movement of sharp distal tip 32 of introducer
needle 31 is shown in FIGS. 46 through 49. In this embodiment,
integrated clip lock 1221 is formed with a spring arm 2191 having a
substantially U-shaped configuration with two legs 2192 wherein the
base of legs 2192 is formed as the retention plate shown in FIG.
37A. Spring arm 2191 is configured such that it is biased outwardly
and can flex into and out of engagement with catheter hub 24.
Preferably, spring arm 2191 is oriented in housing 41 such that the
base of the U is oriented toward the proximal portion of needle
shield 40 and legs 2192 are oriented generally parallel to the
longitudinal axis of introducer needle 31. As discussed in
connection with other embodiments, integrated clip lock 1221 could
have a single leg and a substantially L-shaped configuration. See
for example FIGS. 55 through 57. Extending radially inwardly from
each leg 2192 is a biasing arm 2193. A hole 2194 is defined in each
biasing arm 2193 to allow introducer needle 31 to extend
therethrough. If desired, a flap 2199 is located adjacent to each
hole 2194 extending generally parallel to introducer needle 31.
These flaps 2199 could take the form of turned ends on the biasing
arms 2193 or the cut out flap portion of biasing arms 2193 that are
cut to form holes 2194. Flaps 2199 minimize drag on introducer
needle 31 as it is withdrawn proximally into needle shield 40
through holes 2194.
[0218] In addition, the distal portion of each leg 2192 defines a
hole 2195 therethrough. Holes 2195 are adapted to engage detent 26
formed on the proximal end of catheter hub 24. As discussed above,
detent 26 can have any suitable configuration and the distal
portion of each leg 2192 could likewise have any complementary
configuration so detent 26 and the distal portion of each leg 2192
could be engaged.
[0219] When sharp distal tip 32 of introducer needle 31 extends
past the distal end of needle shield 40 into catheter hub 24,
introducer needle 31 also extends through holes 2194 of biasing
arms 2193. This pulls legs 2192 inwardly toward catheter hub 24 so
holes 2195 engage detent 26. This maintains needle shield 40
connected to catheter hub 24 as long as sharp distal tip 32 of
introducer needle 31 is distal of biasing arms 2193. Once
introducer needle 31 is pulled proximal of biasing arms 2193, legs
2192 are free to return to their unbiased, activated, non-clipped
position where holes 2195 no longer engage detent 26. Thus, spring
arm 2191 can flex into and out of engagement with catheter hub
24.
[0220] Discontinuous portion 38 on introducer needle 31 interacts
with the proximal wall as discussed above to prevent unwanted
proximal movement of introducer needle 31 and with retention plate
1100 to prevent unwanted distal movement of introducer needle
31.
[0221] Alternatively, where it is desired to omit discontinuous
portion 38 from introducer needle 31 one of the biasing arms could
be formed with an extended portion that acts as a transverse
barrier. See FIG. 50. In this third embodiment of the spring clip
1213 having a transverse barrier that connects catheter hub 24 to
needle shield 40 until sharp distal tip 32 has been locked in
needle shield 40, the transverse barrier 396 prevents subsequent
distal movement of introducer needle 31 once sharp distal tip 32 is
withdrawn proximally of biasing arms 393. In addition, in this
embodiment, a tether 50 would have to be used to connect needle
shield 40 and needle hub 34 together to prevent unwanted proximal
movement of introducer needle 31 with respect to needle shield 40
once sharp distal tip 32 is withdrawn into needle shield 40. This
embodiment of spring clip 1213 operates in substantially the same
manner as the spring clip portion of integrated clip lock 1221
shown in the previous embodiment of FIGS. 46-49.
[0222] As with the previous embodiment, each biasing arm 393
preferably has a flap 399 located adjacent to holes 394 extending
generally parallel to introducer needle 31. Flaps 399 minimized rag
on introducer needle 31 as it is withdrawn proximally into needle
shield 40 through holes 394.
[0223] A fourth embodiment of spring clip 1214 having a transverse
barrier that connects catheter hub 24 to needle shield 40 until
sharp distal tip 32 has been locked in needle shield 40 is shown in
FIGS. 51 through 53. This embodiment for spring clip 1214 operates
in substantially the same way as the embodiment shown in FIG. 50.
The only difference is that the ends of biasing arms 493 are formed
with interlocking fingers 497. These fingers 497 facilitate the
locking of each biasing arm 493 to one another once sharp distal
tip 32 of introducer needle 31 is withdrawn proximally behind
biasing arms 493. Preferably, one of biasing arms 493 includes two
spaced fingers 497 extending from the end of that biasing arm while
the other biasing arm includes one finger 497 extending therefrom.
The one finger is adapted to extend through the space created by
the two fingers on the first biasing arm and the two fingers extend
into the space on either side of the one finger on the second
biasing arm. When introducer needle 31 no longer engages biasing
arms 493, the ends of biasing arms 493 move apart so that fingers
497 can extend into their respective spaces and overlap with
appropriate portions of each other and biasing arms 493. With
biasing arms 493 thus locked together via interlocking fingers 497,
a transverse barrier is thereby formed by interlocking fingers 497
to prevent unwanted distal movement of introducer needle 31.
[0224] A second embodiment of integrated clip lock 1222 that
connects needle shield 40 to catheter hub 24 until sharp distal tip
32 of introducer needle 31 is locked in needle shield 40 and that
prevents unwanted distal movement of introducer needle 31 is shown
in FIG. 54. This embodiment is substantially the same as the
embodiment of integrated clip lock 1221 shown in FIGS. 46 through
49 except that in this embodiment a mechanism is provided to
minimize drag on introducer needle 31. In this embodiment, holes
2294 are maintained in alignment by a pin 2280 extending through
separate holes formed in biasing arms 2293. This pin and hole
arrangement maintains holes 2294 in alignment without the edges of
holes 2294 contacting the shaft of introducer needle 31. A tether
2285 connects pin 2280 with needle hub 34. Tether 2285 has a length
such that when introducer needle 31 has been moved proximally so
sharp distal tip 32 of introducer needle 31 is proximal of biasing
arms 2293, tether 2285 pulls pin 2280 proximally out of biasing
arms 2293. At that point, biasing arms 2293 can move outwardly out
of engagement with catheter hub 24.
[0225] A third embodiment of an integrated clip lock 1223 is shown
in FIGS. 55 through 57. In this embodiment of integrated clip lock
1223, the resilient spring arm 2391 is formed with only one leg
2392 such that it would have a substantially L-shaped
configuration. Preferably spring arm 2391 is oriented in housing 41
such that the base is oriented toward the proximal portion of
housing 41 and leg 2392 extends generally parallel to the
longitudinal axis of introducer needle 31. With only one leg 2392,
only one biasing arm 2393 needs to be used. Biasing arm 2393
defines a hole therein through which introducer needle 31 extends.
This embodiment for spring arm 2391 operates in a similar manner to
the embodiment shown in FIGS. 46 through 49 and the distal portion
of leg 2392 can have the same configuration of legs 2192. When
introducer needle 31 extends through the hole in biasing arm 2393,
leg 2392 is pulled inwardly toward and engages catheter hub 24 as
long as sharp distal tip 32 of introducer needle 31 is distal of
biasing arm 2393. Once introducer needle 31 is pulled proximal of
biasing arms 2393, leg 2392 is free to return to its activated,
unbiased, non-clipped position. Thus spring arm 2391 can flex into
and out of engagement with catheter hub 24.
[0226] A fifth embodiment of spring clip 1215 with a transverse
barrier 596 is shown in FIG. 58. In this embodiment, the spring arm
591 is formed with only one leg 592 such that it has a
substantially L-shaped configuration. With only one leg 592, only a
single biasing arm 593 is used. This single biasing arm 593 is
formed with an extended portion that acts as a transverse barrier
596 to prevent subsequent distal movement of introducer needle 31
once sharp distal tip 32 is withdrawn proximally of biasing arms
593. This embodiment of spring clip 1215 operates in substantially
the same manner as the spring clip portion of integrated clip lock
1223 shown in FIGS. 55-57.
[0227] A sixth embodiment of spring clip 1216 having a transverse
barrier is shown in FIGS. 59 through 61. In this embodiment, spring
clip 1216 is formed with a pair of crossed legs 692 to provide a
substantially X-shaped configuration. Spring clip 1216 is
preferably oriented in housing 41 such that base 691 is oriented
toward the proximal portion of housing 41. Each leg 692 defines a
cutout portion or opening 694 therein. These cutout portions 694
allow introducer needle 31 to extend therethrough and provide a
mechanism to allow legs 692 to cross each other. The distal portion
of each leg 692 is biased inwardly and defines a peg 690 thereon.
Pegs 690 are adapted to engage a detents 26 formed on the inside of
catheter hub 24. When introducer needle 31 extends past the distal
end of needle shield 40 into catheter hub 24, introducer needle 31
also extends through cutout portions 694. This pushes legs 692
outwardly toward catheter hub 24 so pegs 690 engage detents 26.
This maintains needle shield 40 connected to catheter hub 24. Once
introducer needle 31 is pulled proximal of cutout portions 694,
legs 692 are free to return to their inward unbiased, non-clipped
position where pegs 690 no longer engage detent 26. Thus spring
clip 1216 can flex into and out of engagement with catheter hub
24.
[0228] A tether 50 could be used in conjunction with spring clip
1216 to prevent unwanted proximal movement of introducer needle 31.
Alternatively, the proximal wall 691 of spring clip 1216 could be
formed as the retention plate shown in FIG. 37A. Thus, introducer
needle 31 could be formed with enlarged diameter portion 38 and
would cooperate with the retention plate in the manner previously
discussed to prevent unwanted distal movement of introducer needle
31.
[0229] As discussed above, the configuration of the portion of the
spring clip in all of the previous embodiments that engage catheter
hub 24, as well as detent 26, could have a wide variety of
configurations. For example, detent 26 could be in the form of a
slot and a radially inwardly extending finger could be disposed on
the portion of the spring clip that engages detent 26. See FIG. 62.
Alternatively, detent 26 could be in the form of a post, which
could be rectangular or have some other geometric shape, and holes,
which could be open ended, could be formed on the portion of the
spring clip that engages detent 26. See FIG. 63. In addition, the
configuration of the holes in the biasing arms that engage the
introducer needle could be open ended such as shown in FIGS. 64 and
65.
[0230] A second embodiment for spring clip 1202 that connects
needle shield 40 to catheter hub 24 is shown in FIGS. 66 through
69. In this embodiment, spring clip 1202 is formed as a separate
piece from retention plate 1100 shown in FIG. 37. Spring clip 1202
is formed with a spring arm 251 and a pair of outwardly biased clip
arms 252. Spring arm 251 is oriented in housing 41 such that the
legs of the U straddle the longitudinal axis of introducer needle
31. Preferably the closed portion of the U is oriented toward the
top of housing 41. However, it is to be understood that spring arm
251 could be in any rotational orientation in the same plane as a
circle concentric to the longitudinal axis of introducer needle 31.
Each clip arm 252 extends generally parallel to the longitudinal
axis of introducer needle 31. Of course it is to be understood that
only one clip arm 252 need be used. A biasing arm 253 extends from
each end of spring arm 251. Biasing arms 253 are generally
perpendicular to the spring arm 251 and the longitudinal axis of
introducer needle 31. Each biasing arm 253 defines a hole 254
therethrough to allow introducer needle 31 to extend therethrough.
Each clip arm 252 defines a hole 255 adjacent to their distal end.
Holes 255 are adapted to engage detent 26 formed on the proximal
end of catheter hub 24. When introducer needle 31 extends past the
distal end of needle shield 40 into catheter hub 24, introducer
needle 31 also extends through holes 254. This pulls biasing arms
253 together and thus pulls clip arms 252 inwardly toward catheter
hub 24 so holes 255 engage detents 26. This maintains needle shield
40 connected to catheter hub 24. Once introducer needle 31 is
pulled proximal of biasing arms 253, spring arm 251 returns to its
unbiased non-clipped position where clip arms 252 are released from
catheter hub 24 so that holes 255 no longer engage detent 26. Of
course as discussed above, the configuration of the distal ends of
clip arms 252 and detent 26 could be changed. For example, detent
26 could be rectangular or have some other geometric shape.
Alternatively, detent 26 could be a slot and a radially inwardly
extending finger could be disposed on the distal end of clip arms
252 to mechanically engage detent 26. The operation of retention
plate 1100 is the same as discussed above with the embodiment of
FIG. 37.
[0231] A seventh embodiment for the spring clip 1217 with a
transverse barrier that prevents unwanted distal movement of
introducer needle 31 once sharp distal tip 32 of introducer needle
31 has been proximally withdrawn into needle shield 40 is shown in
FIGS. 70 through 73. In this embodiment, no enlarged diameter
portion 38 is needed on introducer needle 31. Instead, spring clip
1217 includes a transverse barrier 796 that engages sharp distal
tip 32 of introducer needle 31 to prevent unwanted distal movement
of introducer needle 31. When introducer needle 31 extends through
needle shield 40 so that sharp distal tip 32 is distal of distal
opening 45, introducer needle 31 also extends through holes 794.
This pulls biasing arms 798 together and thus pulls clip arms 792
adjacent to catheter hub 24. Once sharp distal tip 32 is moved
proximally behind holes 794, spring arm 791 moves to its unbiased,
non-clipped position so that transverse barrier 796 is in front of
sharp distal tip 32. This prevents any subsequent unwanted distal
movement of introducer needle. Of course, biasing arms 798 could be
formed with interlocking fingers as disclosed in the embodiment of
FIGS. 51 through 53.
[0232] Using tether 50 to connect needle shield 40 with needle hub
34 prevents unwanted proximal movement of introducer needle 31 with
respect to needle shield 40. As discussed above, tether 50 can take
many different forms such as a string, a pleated element, a sleeve
member surrounding introducer needle 31 or a plurality of
telescoping members surrounding introducer needle 31.
[0233] An eighth embodiment for spring clip 1218 having a
transverse barrier that connects needle shield 40 to catheter hub
24 until sharp distal tip 32 is shielded in needle shield 40 is
shown in FIGS. 74 and 75. In this embodiment, spring clip 1218
includes a clip arm 892 that is pivotally connected to needle
shield 40. Clip arm 892 includes a finger 899 for mechanically
engaging flange 44 of catheter hub 24. With this eighth embodiment
of spring clip 1218, a leaf spring with a transverse barrier 896 to
engage sharp distal tip 32 of introducer needle 31 is used to
prevent unwanted distal movement of introducer needle 31. In the
position shown in FIG. 74, transverse barrier 896 is held in its
outward position by the engagement of the end of transverse barrier
896 with the shaft of introducer needle 31. This holds spring clip
1218 in the clipped position. When introducer needle 31 is
retracted, transverse barrier 896 is no longer constrained by the
shaft of introducer needle 31 and thus moves inward. In this
position, transverse barrier 896 is distal of sharp distal tip 32
and thus locks introducer needle 31 in needle shield 40. Since
transverse barrier 896 is no longer holding clip arm 892 in
position, it can rotate out of engagement with catheter hub 24. See
FIG. 75. Thus, catheter hub 24 can be removed from needle shield
40. Of course it is to be understood that spring clip 1218 of this
embodiment also may be used in conjunction with the leaf spring
disclosed in FIGS. 19 through 21. All that is required is a
mechanism to rotate clip arm 892 into and out of position with
respect to catheter hub 24.
[0234] Another embodiment for spring clip 799 that connects needle
shield 40 to catheter hub 24 until sharp distal tip 32 is shielded
in needle shield 40 is shown in FIGS. 76 and 77. The lock for
preventing unwanted distal movement of introducer needle 31 can be
the embodiment shown in FIGS. 19 through 21.
[0235] When sharp distal tip 32 of introducer needle 31 is distal
of the distal end of needle shield 40, locking leg 730 contacts and
is biased toward introducer needle 31 and spring clip 799, which
acts as a hook, engages flange 44 of catheter hub 24. See FIG. 76.
As introducer needle 31 is withdrawn proximally into needle shield
40 locking leg 730 rides over the surface of introducer needle 31.
Locking leg 730 can include a proximally or distally directed tab
738 that contacts introducer needle 31 to minimize drag on
introducer needle 31. Once sharp distal tip 32 of introducer needle
31 is moved proximal of locking leg 730, leaf spring 700 returns to
its unbiased, i.e. activated, non-clipped position such that
opening 735 is substantially aligned with the longitudinal axis of
introducer needle 31. In this position, spring clip 799 no longer
engages flange 44 of catheter hub 24 so that the catheter can be
disconnected from needle shield 40. See FIG. 77. If introducer
needle 31 is thereafter moved distally with respect to needle
shield 40, sharp distal tip 32 of introducer needle 31 extends
through opening 735 until enlarged diameter portion 38 engages
opening 735. Unwanted distal movement of introducer needle 31 is
thus prevented so that sharp distal tip 32 cannot be re-exposed
outside needle shield 40.
[0236] Locking leg 730 can have a funnel configuration 736 adjacent
to opening 735. This funnel configuration 736 acts as a guide for
introducer needle 31 to ensure that it passes through opening 735
if introducer needle 31 is moved distally after it has been
withdrawn into needle shield 40. Funnel configuration 736 can be
configured so that it is complementary to the shape of the tapered
distal portion 38b of enlarged diameter portion 38 shown in FIG.
3C. Alternatively, locking leg 730 can be replaced with a
transverse barrier arrangement, such as shown in FIGS. 74 and
75.
[0237] In order to place catheter 21 into a patient's blood vessel,
the clinician substantially longitudinally aligns introducer needle
31 and catheter 21 with the target blood vessel. The bevel of sharp
distal tip 32 should be facing substantially away from the skin
surface during venipuncture. The clinician inserts introducer
needle 31 and catheter 21 at a shallow angle, preferably less than
about 35 degrees, into the skin so that sharp distal tip 32 enters
the target blood vessel. The clinician then preferably observes a
blood flashback in the flashback chamber of needle hub 34.
[0238] After confirming placement of introducer needle 31 and
catheter 21 in the target blood vessel, the clinician advances
catheter 21 distally axially along introducer needle 31 into
position in the blood vessel. In certain techniques, introducer
needle 31 may be partially withdrawn into catheter 21 before
catheter 21 is completely advanced into position in the blood
vessel. After proper placement of catheter 21 is achieved, the
clinician places a finger from her other hand on the patient's skin
over the blood vessel approximately over the distal end of catheter
21. By placing her finger on the patient's skin and applying
sufficient pressure on the skin, the clinician thereby
substantially occludes or at least minimizes blood flow through
catheter 21. The clinician then withdraws introducer needle 31
completely from catheter 21 by moving needle hub 34 proximally.
This movement causes introducer needle 31 to move proximally into
needle shield 40.
[0239] Where one of the embodiments of the spring clip disclosed
herein to connect needle shield 40 to catheter hub 24 until sharp
distal tip 32 of introducer needle 31 has been withdrawn into
needle shield 40 is used, needle shield 40 remains engaged with
catheter hub 24 during this proximal movement of introducer needle
31. Once sharp distal tip 32 of introducer needle 31 has been
withdrawn into needle shield 40 so that the lock engages introducer
needle 31 to prevent unwanted distal movement of sharp distal tip
32 of introducer needle 31 out of the distal end of needle shield
40, needle shield 40 can be disconnected from catheter hub 24.
After introducer needle 31 and needle shield 40 have been removed
from catheter hub 24, the clinician may then attach a fluid
delivery device, a PRN, a deadender cap or some other blood
monitoring device to catheter hub 24 and commence the planned
treatment. Introducer needle 31 and needle shield 40 may then be
disposed of according to the facility's disposal protocol.
[0240] Thus, it is seen that a catheter and introducer needle
assembly with needle shield is provided that is compact, simple and
easy to use, that requires no special features or technique to be
operative, that automatically shields the sharp distal tip of the
introducer needle upon withdrawal of the introducer needle from the
catheter and where the needle shield remains connected to the
catheter until the needle shield covers the sharp distal tip of the
introducer needle.
* * * * *