U.S. patent application number 10/419684 was filed with the patent office on 2004-02-12 for needle member with off-set flash chamber and/or display member.
Invention is credited to Holdaway, Richard G., Kinsey, P. Spencer.
Application Number | 20040030291 10/419684 |
Document ID | / |
Family ID | 26801656 |
Filed Date | 2004-02-12 |
United States Patent
Application |
20040030291 |
Kind Code |
A1 |
Holdaway, Richard G. ; et
al. |
February 12, 2004 |
Needle member with off-set flash chamber and/or display member
Abstract
A needle assembly (10) for insertion or removal of fluids has a
housing (20) that defines a flash chamber (64) that is radially
offset from the longitudinal axis of the needle. An enhanced
surface area display member (80) can be installed in an observable
location in a needle housing (20) to facilitate observation of the
fluid therein.
Inventors: |
Holdaway, Richard G.;
(Storrs, CT) ; Kinsey, P. Spencer; (Vernon,
CT) |
Correspondence
Address: |
KNOBBE MARTENS OLSON & BEAR LLP
2040 MAIN STREET
FOURTEENTH FLOOR
IRVINE
CA
92614
US
|
Family ID: |
26801656 |
Appl. No.: |
10/419684 |
Filed: |
April 18, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10419684 |
Apr 18, 2003 |
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09807562 |
Apr 12, 2001 |
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6623456 |
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09807562 |
Apr 12, 2001 |
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PCT/US99/24254 |
Oct 15, 1999 |
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60104531 |
Oct 16, 1998 |
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60104537 |
Oct 16, 1998 |
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Current U.S.
Class: |
604/164.08 |
Current CPC
Class: |
A61M 25/0693 20130101;
A61M 2005/3212 20130101; A61M 5/321 20130101; A61M 25/0643
20130101 |
Class at
Publication: |
604/164.08 |
International
Class: |
A61M 005/178 |
Claims
What is claimed is:
1. A needle member comprising: a needle cannula having a needle
axis; and a housing on which the needle cannula is mounted, the
housing being at least partially translucent and dimensioned and
configured to define a translucent flash chamber offset from but
substantially parallel to the needle axis and in fluid
communication with the needle cannula.
2. A needle member comprising: a needle cannula having a needle
axis; and a housing, the needle cannula mounted on the housing, the
housing dimensioned and configured to define an access port offset
from but substantially parallel to the needle axis.
3. A needle member comprising: a needle cannula having a needle
axis; and a housing on which the needle cannula is mounted, the
housing being at least partially translucent and dimensioned and
configured to define a translucent flash chamber in fluid
communication with the needle cannula; and a display member
disposed within the housing.
4. The needle member of claim 3, wherein the display member is
disposed within the flash chamber.
5. The needle member of claim 3, wherein the display member
comprises a plurality of slats.
6. The needle member of claim 3, wherein the display member
comprises a perforated tube disposed in the flash chamber.
7. The needle member of claim 1, claim 2 or claim 3, in combination
with: a blunting member comprising an elongate probe that has a
blunt tip, the probe being disposed within the needle cannula, the
probe being dimensioned and configured to be accommodated within
the needle cannula while leaving the needle cannula open to fluid
flow therethrough, the blunting member being movable between a
retracted position in which the blunt tip of the blunting member is
disposed within the needle cannula and a deployed position in which
the blunt tip protrudes outwardly of and thereby blunts the tip of
the needle cannula.
8. The needle member of claim 7, wherein the probe is hollow and is
in fluid communication with the flash chamber.
9. The needle member of claim 7, wherein the probe is solid.
10. A needle member comprising: a needle cannula having a needle
axis; a housing, the needle cannula mounted on the housing, the
housing being at least partially translucent and dimensioned and
configured to define a flash chamber substantially offset from but
substantially parallel to the needle axis and in fluid
communication with the needle cannula; and a display member having
an enhanced blood surface area disposed within the housing.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. provisional
application No. 60/104,531, filed Oct. 16, 1998 and from U.S.
provisional application No. 60/104,537, filed Oct. 16, 1998.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a needle member especially
suited for use as a hypodermic needle and for use with a catheter.
More particularly, the present invention relates to a needle member
that includes a flash chamber for the detection of fluid
therein.
[0004] 2. Related Art
[0005] Needle and catheter arrangements for removal or insertion of
fluids through the epidermis of a patient are well known.
Healthcare workers using needles and catheters often have
difficulty in accurately locating and puncturing a vein inside a
patient, making necessary multiple insertions of the needle which
cause discomfort to the patient. One mechanism to aid in locating
veins is a flash chamber, a clear or translucent chamber located
behind the proximate end of the cannula, allowing the user to see
the blood as it exits the needle. This first showing of blood is
called "flash". By watching for flash, the user can verify that the
tip of the hypodermic needle has entered the vein and thus the user
can cease penetration of the patient's flesh before the distal end
of the needle penetrates the far side of the vein.
[0006] Another aid to healthcare workers attempting accurate
placement of cannulae is a hypodermic needle which allows insertion
at a wide range of angles, especially angles in which the
hypodermic needle is substantially parallel to the epidermis of the
patient.
[0007] Yet a third feature which aids venipuncture is a catheter
and hypodermic needle arrangement which is modular and allows easy
addition and removal of accessories as required.
[0008] U.S. Pat. No. 5,009,642 to C. R. Sahi, dated Apr. 23, 1991
and entitled "SELF-BLUNTING NEEDLE ASSEMBLY WITH A CATHETER, AND
CATHETER ASSEMBLY USING THE SAME", discloses a self-blunting needle
assembly (10) for use with a catheter (40). The needle assembly
(10) includes a needle (12) that comprises a transparent fluid
collection tube (or "flash chamber") (24) secured to a needle shaft
(14) (see FIG. 4). The needle (12) also includes an elongate probe
(30) movably disposed within the needle shaft (14). Prior to use,
the catheter is placed over the needle shaft and is positioned to
engage the probe. The needle shaft is then used to introduce the
catheter into a vein. When venipuncture is achieved, blood flows
through the needle shaft into the collection tube, giving the user
a visual indication that the needle and catheter are properly
positioned. The needle assembly can then be withdrawn to allow use
of the catheter in a conventional manner. Since the catheter
engages the probe, withdrawal of the needle member from the
catheter advances the probe within the needle so that the withdrawn
needle assembly becomes blunted after having been used. The
collection tube and needle shaft are both generally cylindrical in
configuration and are co-axially disposed relative to each other.
The diameter of the collection tube, however, is several times
greater than the diameter of the needle shaft and catheter, so that
the collection tube limits the angles at which the needle may be
introduced into the patient's vein.
[0009] U.S. Pat. No. 5,374,252 to Banks et al, dated Dec. 20, 1994
and entitled "LOCKING PNEUMONEEDLE", discloses a pneumoneedle that
comprises a cannula (20) mounted in a housing (12) (see FIG. 1).
The housing (12) also contains a tubular protector (or "blunting
member") (31) disposed within the cannula and movable between a
retracted position in which the sharp tip of the cannula is exposed
and a deployed position in which the blunt end (32) of the
protector extends beyond the sharp tip of the cannula. The
protector (31) is tubular and has a distal aperture (36) that is
exposed when the protector is moved to the deployed position. There
is also a proximal aperture (35) that opens to an internal fluid
passageway portion of the housing (12). A fluid conduit (8) in the
housing communicates with fluid passageway portion (18) and extends
at an angle relative to the longitudinal axis of the needle
cannula. The device is used for introducing an insufflating gas
into the abdominal cavity of a patient via the fluid conduit. To
determine whether the sharpened tip of the cannula, and therefore
the distal aperture of the protector, are properly positioned, a
saline/vacuum test must be performed. In this test, the device is
primed with a small reserve of saline solution via the fluid
conduit (8) and the device is inserted into the patient. The
patient's abdomen is manipulated and if fluid communication has
been established between the abdominal cavity and the device, the
saline will be seen to surge. There is no indication or suggestion
that the level of saline can be seen through the device housing,
i.e., that the housing is translucent, or that the device may be
adapted for intravenous use or that the fluid conduit be used for
anything other than introducing an insufflating gas into the
protector. In the medical field, pneumoneedles are considered to
relate to a function that is disparate from that of intravenous
fluid flow and the knowledge in the art pertaining to pneumoneedles
is not seen as analogous or pertinent to intravenous needles.
[0010] U.S. Pat. No. 5,120,319 to Van Heugten et al, dated Jun. 9,
1992 and entitled "FLASH TUBE FOR INTRAVENOUS CATHETER", discusses
some of the problems associated with flash chambers. As pointed out
in this reference, when using small needles in small veins, quick
flashback and quick reaction speed are more important than in
larger veins. However, a larger flashback chamber is necessary when
examining the blood flow to verify that it is continuing and thus
there is a trade-off between large and small flash chambers. Van
Heugten et al teaches a flash chamber having a capillary tube which
will quickly fill with blood. Owing to the diffraction properties
of the glass tube, the outside diameter of the tube appears to be
red. This is combined with a conventional, larger, flash chamber
allowing healthcare workers to verify continued flow of blood.
While Van Heugten et al aids the healthcare worker in detecting the
flash, the presented apparatus does not assist in successful
venipuncture at angles close to parallel with the epidermis of the
patient nor does Van Heugten et al teach any self-blunting
mechanism.
[0011] U.S. Pat. No. 5,697,914 to G. L. Brimhall, dated Dec. 16,
1997 and entitled "CONTROL FORWARD/FLASHBACK FORWARD ONE HAND
INTRODUCER NEEDLE AND CATHETER ASSEMBLY", is another
non-self-blunting design which improves visibility of flash, by
using an angled flash chamber. Brimhall also teaches a method for
the healthcare worker/user to withdraw the needle within the
catheter. However, Brimhall's needle is not automatically
self-blunting, nor is there any method other than the angled nature
of the flash chamber, to improve visibility of blood within the
flash chamber. Finally, the wide fins projecting at various angles
from the body of Brimhall's catheter assembly restrict motion at
some orientations of the assembly.
[0012] It would be advantageous to provide a needle member with
improved flash visualization which allows easy placement of the
needle at any orientation even at angles parallel to the epidermis
of the patient, and with easy access to a luer connection. It would
further be advantageous if the catheter and needle assembly were
held aligned while the catheter is removed from the needle assembly
after insertion into the patient.
SUMMARY OF THE INVENTION
[0013] The invention provides a needle member comprising a needle
cannula having a needle axis and a housing on which the needle
cannula is mounted, the housing being at least partially
translucent and dimensioned and configured to define a translucent
flash chamber offset from but substantially parallel to the needle
axis and in fluid communication with the needle cannula.
[0014] In another aspect, the invention provides a needle member
comprising a needle cannula having a needle axis and a housing, the
needle cannula mounted on the housing, the housing dimensioned and
configured to define an access port offset from but substantially
parallel to the needle axis.
[0015] Another aspect of the invention provides a needle member
comprising a needle cannula having a needle axis and a housing on
which the needle cannula is mounted, the housing being at least
partially translucent and dimensioned and configured to define a
translucent flash chamber in fluid communication with the needle
cannula, and a display member disposed within the housing.
[0016] Another aspect of the invention provides a display member
disposed within the flash chamber.
[0017] Another aspect of the invention provides a display member
comprising a plurality of slats.
[0018] Yet another aspect of the invention provides a display
member comprising a perforated tube disposed in the flash
chamber.
[0019] Yet another aspect of the invention provides a blunting
member comprising an elongate probe that has a blunt tip, the probe
being disposed within the needle cannula. The probe is dimensioned
and configured to be accommodated within the needle cannula while
leaving the needle cannula open to fluid flow therethrough and the
blunting member is movable between a retracted position in which
the blunt tip of the blunting member is disposed within the needle
cannula and a deployed position in which the blunt tip protrudes
outwardly of and thereby blunts the tip of the needle cannula.
[0020] Yet another-aspect of the invention provides a probe which
is hollow and is in fluid communication with the flash chamber.
[0021] Yet another aspect of the invention provides a probe which
is solid.
[0022] Yet another aspect of the invention provides a needle member
comprising a needle cannula having a needle axis and a housing, the
needle cannula mounted on the housing, the housing being at least
partially translucent and dimensioned and configured to define a
flash chamber substantially offset from but substantially parallel
to the needle axis and in fluid communication with the needle
cannula, and a display member having an enhanced blood surface area
disposed within the housing.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] FIG. 1 is a perspective view of a catheter and needle
assembly in accordance with a particular embodiment of the present
invention;
[0024] FIG. 1A is a cross-sectional view in elevation of the needle
member of the assembly of FIG. 1;
[0025] FIG. 1B is a cross-sectional view in elevation of a blunting
member for use with the needle member of FIG. 1A;
[0026] FIG. 2 is a cross-sectional view in elevation of the
catheter and needle assembly of FIG. 1;
[0027] FIG. 3 is a view like that of FIG. 2 showing the needle
assembly separating from the catheter and with the blunting member
in its deployed position;
[0028] FIG. 4 is a cross-sectional view in elevation of a needle
member in accordance with another embodiment of the present
invention;
[0029] FIG. 4A is a cross-sectional view in elevation of a needle
assembly in accordance with another embodiment of the present
invention;
[0030] FIG. 5 is a perspective view of a display member according
to a particular embodiment of the present invention;
[0031] FIG. 6 is a schematic cross-sectional view of a needle
member including the display member of FIG. 5;
[0032] FIG. 7A is a perspective view of a display member according
to another embodiment of the invention; and
[0033] FIG. 7B is a cross-sectional view of the display member of
FIG. 7A taken along line 7B-7B.
DETAILED DESCRIPTION OF THE INVENTION AND PREFERRED EMBODIMENTS
THEREOF
[0034] The present invention provides a needle member comprising a
needle cannula mounting in a housing designed to facilitate
manipulation of the needle and to give the user a visual indication
of proper placement of the needle for fluid transfer to or from a
patient. At least part of the housing comprises a translucent
material that defines a chamber, referred to herein and in the
claims as a "flash chamber", that is in fluid communication with
the needle cannula. In accordance with the present invention, and
in contrast to the prior art in the field of intravenous needles,
the housing is dimensioned and configured to define an elongate
flash chamber which is disposed substantially parallel to, but
offset from, the needle axis.
[0035] A flash chamber is typically much larger in cross-sectional
dimension than the needle cannula to which it is connected.
Accordingly, the flash chamber in a prior art needle member limits
how closely to the surface of the user's skin the needle can be
disposed during insertion because the chamber protrudes
significantly in all radial directions about the axis of the
needle. Even when the housing of a prior art catheter needle member
is pressed against the skin, the needle therein is necessarily
raised above the surface of the skin to a significant degree. In
addition, a prior art needle member with an axially aligned flash
chamber typically includes an access port for the connection of
other fluid-transfer devices, such as a syringe, a luer connector,
etc., to the needle member, and the access port is disposed axially
on the flash chamber opposite from the needle. Therefore, devices
being connected to the needle member must be aligned with the
needle and, if connection is being made while the needle is in a
patient's vein, the connecting device will have to be situated
close to the patient's skin. This can make proper manipulation of
the connecting device awkward.
[0036] In a needle member in accordance with one aspect of the
present invention, the flash chamber is offset from the
longitudinal axis of the needle cannula, and so protrudes
principally in one particular direction from the needle cannula. In
such configurations the flash chamber resides principally, i.e.,
protrudes most prominently, toward a particular radial direction
about the needle axis, and leaves a potentially large region of
minimal protrusion in other radial directions. By positioning part
of a circumferentially large region of minimal protrusion towards
the patient's skin, the user has greater freedom to angle the
needle more closely against the patient's skin during use than if
the center of the flash chamber were aligned with the needle axis.
One embodiment of the present invention provides a needle member in
which the radial distance from the longitudinal axis of the needle
to the radial periphery of the housing about the flash chamber,
i.e., the radial thickness of the housing, may be reduced in at
least one radial direction, thus giving the housing a region of
reduced radial thickness. In turn, when the needle assembly is
placed with the reduced radial thickness adjacent the patient's
skin, the entry angle required for the needle may be reduced or
flattened. In some embodiments, this advantage may be realized even
if the flash chamber is larger than in a prior art embodiment in
which a smaller flash chamber is aligned with the needle axis. Thus
an operator has an increased range of motion for finding and
properly introducing a catheter into a vein of a patient. In other
embodiments of the invention, the region of minimal protrusion or
reduced radial thickness can be occupied by optional additional
structures (such as the self-blunting mechanism disclosed below),
so the invention permits the incorporation of the additional
structures into the device without unduly increasing the radial
thickness of the device. The additional structures therefore need
not impose a greater limitation on the orientation of the needle
than would be encountered with a conventional, prior art needle
that lacked such structures. In addition, the flash chamber is
typically cylindrical in configuration, or may otherwise define a
longitudinal axis, e.g., as a result of having an elongate
configuration, and the longitudinal axis of the flash chamber is
substantially parallel to that of the needle. In other words, the
flash chamber is not only offset from the needle axis, it is
disposed with its longitudinal axis parallel to the needle
axis.
[0037] Another, independent feature of the present invention is
that the access port (or "luer access"), by which another
fluid-flow device, such as a syringe, luer connector, etc., may be
coupled to the needle member, is offset from the axis of the needle
cannula. In a typical embodiment of this invention, this is
achieved by positioning the access port on the off-set flash
chamber, e.g., in line with the longitudinal axis of an off-set
longitudinal flash chamber. However, this aspect of the invention
may be practiced even in conjunction with a conventionally disposed
(i.e., axially aligned) flash chamber, e.g., by disposing the
access port on the side of the housing rather than at the end of
the flash chamber. One advantage of having an off-set access port
is that the access port is thereby distanced from the patient's
skin, thus giving the user more freedom of movement in coupling
another fluid-handling device to the needle member.
[0038] By providing the flash chamber on the needle member as
described herein, the advantages of the present invention can be
achieved with a conventional catheter. Once the catheter is
properly placed, using the introducer needle and the associated
flash chamber, the needle member can then be withdrawn from the
catheter, which is then positioned for use in a conventional
manner. Thus, the present invention provides a contrast to prior
art catheter assemblies such as that shown in U.S. Pat. No.
5,697,914 to Brimhall (discussed above), which requires the use of
a catheter that is specifically configured to incorporate the flash
chamber.
[0039] Still another feature of the present invention is the
incorporation into a needle housing of a display member. The
display member is disposed in a visually discernible location in
the path of fluid flow through the housing, optionally in a flash
chamber, and is configured to provide an enhanced surface area on
which fluid spreads and is visible. The fluid in the needle
housing, e.g., blood, quickly wets the surface of the display
member and thus augments the visual signal of fluid flow provided
by the flash chamber.
[0040] Referring now to the drawings, a catheter and hypodermic
needle assembly in accordance with a particular embodiment of the
present invention is generally indicated at 10 of FIG. 1. The
catheter and needle assembly 10 includes a catheter 12 and a needle
member 14. Catheter 12 comprises a hub 16 from which extends a
catheter tube 18. Needle member 14 includes a tubular needle
cannula 24 (seen protruding from tube 18 of catheter 12) that is
mounted in housing 20 and that has a longitudinal axis A.
[0041] Housing 20 defines a generally longitudinal, e.g.,
cylindrical, flash chamber 64 that is in fluid communication with
needle cannula 24. The center of flash chamber 64 is positioned on
axis F that is parallel to axis A and it can be seen that flash
chamber 64 is therefore offset from axis A. Side portions 28 of
housing 20 may be generally flat in shape so they may be easily
gripped by a user such as a healthcare worker. In other
embodiments, housing 20 and side portions 28 of housing 20 may be
configured to yet further reduce the thickness of the device.
Housing 20 may also include a cover mount 29 for mounting of a
suitable cover (not shown), to further prevent stick wounds prior
to use of catheter and needle assembly 10. Housing 20 of needle
member 14 may also be formed of any suitably moldable and durable
material such as a polyolefin plastic, polycarbonate, SAN
(styrene-acrylonitrile copolymer) or ABS
(acrylonitrile-butadiene-styrene copolymer) or the like. At least a
portion of housing 20 that defines flash chamber 64 will be formed
of a translucent material so that the user can see when blood has
entered the device. As used herein and in the claims, the term
"translucent material" is meant in a broad sense and should be
understood to include transparent material or any other materials
that permit visual perception of fluid therein. As shown in FIG. 1,
tube 18 of catheter 12 is disposed over, and in co-axial
relationship with, needle cannula 24, and the sharp tip of needle
cannula 24 protrudes past the tip of tube 18. Assembly 10 is
therefore ready for use. A mounting portion 26 may be provided on
hub 16 for mating catheter 12 with an intravenous ("IV") tube (not
shown). Hub 16 is typically formed from a polyolefin material.
[0042] In FIG. 1A, needle cannula 24 is seen in a cross-sectional
view to be mounted in a needle hub 20a which, in turn, is secured
to housing body 20b. Together, needle hub 20a and housing body 20b
comprise housing 20. The proximal end of needle cannula 24 opens to
an antechamber 64a in housing 20, which opens via a gap 64b to
flash chamber 64. Flash chamber 64 is generally cylindrical in
configuration and its center is disposed on an axis F that is
substantially parallel to the longitudinal axis A of needle cannula
24. In accordance with the present invention, the center of flash
chamber 64 is offset from axis A by a distance d. Flash chamber 64
therefore principally protrudes, i.e., it is offset, in a radial
direction upward (as sensed in FIG. 1A) and not at all in the
opposite radial direction or in the two lateral directions
perpendicular thereto. It may also be clearly seen in FIG. 1A that
the flow path between flash chamber 64 and needle cannula 24
through gap 64b must have a generally non-parallel orientation
relative to axis A. In other words, for fluid to flow from needle
cannula 24 to flash chamber 64, the flow path must have a radial
component to it, i.e., the fluid must flow in a direction having a
component perpendicular to axis A.
[0043] The embodiment shown in FIGS. 1 and 1A makes use of the
upward offset of the flash chamber to permit the placement of
optional additional structures in a direction opposite flash
chamber 64, i.e., downward from axis A. Specifically, housing 20 is
dimensioned and configured to accommodate a blunting mechanism
within the space indicated at d' between axis A and periphery B,
which is positioned radially opposite from flash chamber 64. To
accommodate the blunting mechanism, housing 20 comprises a
generally U-shaped channel 46 that defines a central passageway 37
and that has a flat outer surface 48 for contact with a patient's
skin. Alternatively, either of side portions 28 could be disposed
against the patient's skin to permit an even flatter angle of entry
of the needle into the skin. In other embodiments, the blunting
mechanism may be accommodated on either side of housing 20 or may
be omitted, as shown in FIG. 4.
[0044] Housing 20 defines a blunting member aperture 31 through
which a blunting member 33 can be positioned for axial insertion
into needle cannula 24. Blunting member 33 for use with needle
cannula 24 of FIG. 1A is shown in FIG. 1B. Blunting member 33
comprises an elongate probe 34 having a blunt tip 35. Probe 34 is
mounted in a mounting ferrule 33a that is dimensioned and
configured to sealingly engage bushing 58 in blunting member
aperture 31. Probe 34 is dimensioned and configured so that it can
be inserted through aperture 31 and into needle cannula 24 so that,
when mounting ferrule 33a is fully inserted in aperture 31, tip 35
will extend beyond, and thus obscure, the sharp tip of needle
cannula 24, thus blunting the needle member 14. Probe 34 may be
hollow or solid, but in either case it is configured so that it
does not prevent the flow of fluid through needle cannula 24.
Mounting ferrule 33a comprises part of a shuttle 36, which is
dimensioned and configured to be received within passageway 37 and
which comprises a latch portion 38 that is configured to engage the
catheter hub as will be described further below.
[0045] FIG. 2 shows that catheter hub 16 includes a central bore 42
that is configured to receive needle member 14 therein. A reduced
diameter portion of central bore 42 may include a sleeve 44,
optionally formed of metal, for receiving needle cannula 24 and
preventing damage to catheter hub 16 or to the tip of needle
cannula 24 when catheter 12 is sliding over needle cannula 24 to
engage needle hub 20a and probe 34.
[0046] FIG. 2 illustrates the catheter and needle assembly 10 in a
sharpened configuration, i.e., with needle cannula 24 protruding
from catheter tube 18 so that needle assembly 10 is ready for use
in introducing catheter 12 into a paticnt's vein. Hub 16 of
catheter 12, which is specially configured to engage latch portion
38 of shuttle 36, has positioned blunting member 33 in the
retracted position, leaving the sharp tip of needle cannula 24
exposed. When venipuncture is achieved, blood enters needle cannula
24 and flows into hollow interior 60 of probe 34, then leaves probe
34 via aperture 62 and flows in a non-axial direction into flash
chamber 64 via gap 64b. Housing 20 carries a schematically
indicated flash plug 22a at access port 22 to prevent leakage. At
least a portion of housing 20, defining flash chamber 64, is
transparent or otherwise translucent so that the user can see when
blood flows therein. Flash plug 22a is vented to allow air to
escape but it is configured to prevent leakage of fluid. Flash plug
22a may be puncturable or removable to permit the optional
introduction or withdrawal of fluids through flash chamber 64, if
desired. In this way, once the user has confirmed venipuncture by
visual inspection of flash chamber 64, access port 22 can be used
for the introduction or withdrawal of fluids into or from the
patient's vein via assembly 10 by another fluid-handling device
connected thereto. When the necessary healthcare functions have
been performed and it is desired to remove needle cannula 24 from
the patient and leave catheter 12 in place for later use, needle
member 14 can be withdrawn from catheter 12 (which may then be
stoppered or connected to an IV line), whereby shuttle 36 is pulled
forward due to the engagement of latch portion 38 with catheter 12,
thus moving blunting member 33 forward to the deployed position and
blunting tip 35 of needle cannula 24. As illustrated in FIG. 3,
upon removal of catheter 12 from needle member 14, aperture 62 is
moved out of communication with flash chamber 64 and sealed
adjacent the interior bore of needle cannula 24.
[0047] In accordance with another embodiment of the invention, a
needle member having an axially-displaced flash chamber can be
employed without allowing for additional mechanisms, so that the
needle member housing can have a radial region of reduced thickness
relative to the needle axis. For example, FIG. 4 shows a particular
embodiment of the invention in which a needle member 14' comprises
a housing 20' in which needle cannula 24 is mounted. Housing 20'
defines a flash chamber 64 and an access port 22. As with
previously illustrated embodiments, flash chamber 64 is axially
offset from needle axis A by distance d. However, housing 20' does
not include the U-shaped channel designed to accommodate a blunting
mechanism as in the embodiment of FIGS. 1-3. Accordingly, in the
region radially opposite from flash chamber 64, needle member 14'
presents a very small radial thickness d". This small radial
thickness or protrusion in the region opposite from flash chamber
64 allows the healthcare worker to insert needle 24 at a very low
angle relative to the patient's skin. At the same time, as
mentioned above in connection with the embodiment of FIGS. 1
through 3, access port 22 will be situated above the patient's
skin, providing convenient access for the healthcare worker and
added safety and comfort to the patient. Needle member 14' can be
used for the introduction of a conventional catheter the same way
as described above for needle member 14. Similarly, the thickness
of the needle member in directions generally lateral, e.g.,
perpendicular, to the radical direction of displacement of the
flash chamber may be small as well.
[0048] FIG. 4A illustrates another alternative embodiment of the
invention. In this embodiment, needle hub 20a does not have the
extended nose configuration.
[0049] Still another, independent, feature of the present invention
relates to the positioning of a display member in a visually
discernible location in the needle assembly, so that the display
member is contacted by the fluid flowing therethrough. The display
member is dimensioned and configured to have a higher surface area
for contact by the fluid than the interior of the needle assembly
in the vicinity where the display member is disposed. Since the
fluid flowing through that portion of the device contacts a larger,
and more visually discernible, surface area than it otherwise would
in that region of the device, the display member of this aspect of
the invention increases the visibility of the fluid. One example of
a display member in accordance with this aspect of the present
invention is shown in FIG. 5. Display member 80 comprises an
optional mounting ferrule 82 which is generally cylindrical in
shape and has an interior passage therethrough, and which is
configured to receive a needle hub therein. Display member 80
further comprises optional mounting flanges 84 that are dimensioned
and configured to engage the housing and secure display member 80
thereto. The aperture also opens rearward to where display member
80 comprises longitudinally-extending slats 86 which are
interconnected via mounting ferrule 82. Slats 86 terminate at a
sealing ring 88 that optionally forms an access aperture 90
dimensioned and configured to receive a blunting member and/or to
facilitate fluid flow to or through the flash chamber.
[0050] FIG. 6 shows an alternative embodiment of needle member 14"
in which display member 80 (FIG. 5) is mounted in a needle housing
20" in a region corresponding to antechamber 64a of needle member
14. Sealing ring 88 is positioned and sealed to the housing at
blunting member aperture 31 so that access aperture 90 (FIG. 5)
communicates with blunting member aperture 31. Access aperture 90
(FIG. 5) is dimensioned to receive probe 34 and mounting ferrule
33a and so does not interfere with the function of blunting member
33 (FIG. 1B). At the opposite end of display member 80, mounting
flanges 84 and the portion of display member 80 rearward thereof
sealingly engage housing 20". Mounting ferrule 82 extends forward
from housing 20". Needle cannula 24 is mounted in mounting ferrule
82. The interior of needle cannula 24 opens to the interior of
mounting ferrule 82. Accordingly, fluid such as blood, flowing from
the patient through needle cannula 24, passes through mounting
ferrule 82 and comes into contact with slats 86 that extend between
mounting ferrule 82 and sealing ring 88. The blood quickly wets the
surfaces of slats 86 upon entry into housing 20". The presence of
display member 80 in housing 20" causes fluid initially entering
the housing to be dispersed over a relatively large, visible
surface area instead of allowing it to pool or agglomerate within
the housing antechamber. Display member 80 provides a much higher
visibly discernible surface area than does the interior of the
antechamber in which it is positioned. By disposing the wetted
surfaces of slats 86 in a translucent portion of the device, the
user is provided with a visual indication that fluid is flowing
into the device; that indication is provided more quickly and
offers greater ease of visual recognition than with devices that
are not equipped with an enhanced surface area display member
and/or in which only the flash chamber is formed from translucent
material. The improved visibility is achieved via the flash chamber
and, if the antechamber is formed from translucent material, via
the antechamber, before the fluid fills or even enters the flash
chamber 64.
[0051] The display member may have any configuration that increases
the visually discernible surface area within the needle member
housing. The display member generally has a non-tubular
configuration, i.e., it preferably is not configured as a simple,
unperforated or unslotted tube. For example, instead of a plurality
of slats, a display member in accordance with the present invention
may comprise a longitudinally slotted or otherwise perforated
cylinder, as illustrated in FIGS. 7A and 7B. FIG. 7A shows display
member 80' having substantially the same configuration as display
member 80 of FIG. 5, except that instead of slats 86, display
member 80 comprises a slotted cylindrical portion 86' having a
longitudinally extending slot 86a. Blood or another fluid flowing
into the interior of portion 86' will exit via slot 86a and then
wet the exterior surface of cylindrical portion 86' before filling
the chamber within which display member 80' is disposed. Once
again, the visible surface area on which blood disperses is
enhanced. Since the effect of the display member derives
principally from the surface area it provides inside a needle
housing, the display member may optionally be an opaque
structure.
[0052] It will be understood from the foregoing that the benefits
of a display member can be obtained whether the chamber within
which it is disposed is aligned with the needle cannula or is
displaced from the axis of the needle. For example, in various
embodiments, a display member may be employed in a needle member
having either an aligned flash chamber or an off-set flash chamber
to increase the visible surface area therein. According to still
other embodiments, the display member may reside entirely within
the needle housing and need not comprise either of a mounting
ferrule for receiving a needle hub or an access aperture for
receiving a blunting member.
[0053] While the invention has been described in detail with
reference to particular embodiments thereof, upon a reading and
understanding of the foregoing, numerous alterations to the
described embodiments will occur to those skilled in the art, and
it is intended to include such alterations, substitutions and
equivalents within the scope of the appended claims.
* * * * *