U.S. patent application number 10/320274 was filed with the patent office on 2003-06-26 for blood seal having a spring-biased septum.
Invention is credited to Howell, Glade H..
Application Number | 20030120214 10/320274 |
Document ID | / |
Family ID | 25228307 |
Filed Date | 2003-06-26 |
United States Patent
Application |
20030120214 |
Kind Code |
A1 |
Howell, Glade H. |
June 26, 2003 |
Blood seal having a spring-biased septum
Abstract
A blood seal having a spring-biased septum is provided for
preventing the leakage of blood during the placement and use of
vascular catheters and similar devices. The structure of the blood
seal includes a housing with an internal channel. A spring-biased
septum is placed securely within the channel such that it
substantially blocks blood flow through the channel. The
spring-biased septum includes an elastic plug having a pre-slit or
pre-molded hole and a biasing element disposed about the elastic
plug. A needle or other object may be withdrawn through the slit or
hole, after which the biasing element forces the hole closed,
preventing blood leakage.
Inventors: |
Howell, Glade H.; (Sandy,
UT) |
Correspondence
Address: |
BECTON, DICKINSON AND COMPANY
1 BECTON DRIVE
FRANKLIN LAKES
NJ
07417-1880
US
|
Family ID: |
25228307 |
Appl. No.: |
10/320274 |
Filed: |
December 16, 2002 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10320274 |
Dec 16, 2002 |
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09819490 |
Mar 28, 2001 |
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Current U.S.
Class: |
604/167.03 |
Current CPC
Class: |
A61M 39/045 20130101;
A61M 39/0693 20130101; A61M 2039/062 20130101; Y10T 137/7771
20150401; A61M 39/0613 20130101; Y10T 137/7881 20150401; Y10T
137/7877 20150401 |
Class at
Publication: |
604/167.03 |
International
Class: |
A61M 005/178 |
Claims
What is claimed and desired to be secured by Letters Patent is:
1. A spring-biased septum for use in a medical device comprising:
an elastic plug having a slit disposed longitudinally through the
plug; a biasing element contacting the plug and disposed such that
the biasing element urges the longitudinal slit into a closed
position.
2. A spring-biased septum as defined in claim 1 wherein the biasing
element is placed in contact with the outer surface of the elastic
plug.
3. A spring-biased septum as defined in claim 1 wherein said
elastic plug further comprises an annular groove disposed in the
outer surface of the plug.
4. A spring-biased septum as defined in claim 3 wherein said
biasing element is disposed within said annular groove.
5. A spring-biased septum as defined in claim 1 wherein said slit
is formed such that a hypodermic needle can be passed through said
slit.
6. A spring-biased septum as defined in claim 1 wherein the biasing
element comprises a C-shaped spring.
7. A spring-biased septum comprising: an elastic plug comprising an
annular groove; a slit disposed longitudinally through the elastic
plug; and a biasing element contacting said plug and disposed
within the annular groove of the elastic plug such that the biasing
element substantially closes the slit to fluid leakage.
8. A spring-biased septum as defined in claim 7, wherein the
elastic plug is constructed of a biocompatible elastomer.
9. A spring-biased septum as defined in claim 7, wherein the
elastic plug is constructed of latex or polyisoprene.
10. A spring-biased septum as defined in claim 7, wherein the
biasing element comprises a C-shaped spring.
11. A spring-biased septum as defined in claim 10, wherein the
C-shaped spring is constructed of a metal or a metal alloy.
12. A spring-biased septum as defined in claim 10, wherein the
C-shaped spring is constructed of spring steel.
13. A blood seal comprising: a housing; an internal channel
disposed through the housing; an elastic plug disposed within and
substantially blocking the internal channel; a slit disposed
longitudinally through the elastic plug; and a biasing element
contacting the elastic plug such that the biasing element
substantially closes the slit to fluid leakage.
14. A blood seal as defined in claim 13, wherein the elastic plug
further comprises an annular groove disposed in the outer surface
of the plug.
15. A blood seal as defined in claim 13, further comprising a
needle disposed longitudinally within the internal channel such
that at least a portion of the needle passes through the hole in
the elastic plug.
16. A blood seal as defined in claim 13, further comprising a wire
disposed longitudinally within the internal channel such that at
least a portion of the wire passes through the hole in the elastic
plug.
17. A blood seal as defined in claim 16, wherein the wire is
attached to a needle.
18. A blood seal as defined in claim 13, further comprising a
cannula disposed longitudinally within the internal channel such
that at least a portion of the cannula passes through the hole in
the elastic plug.
19. A blood seal as defined in claim 13, further comprising a rigid
plug retainer disposed within the internal channel such that the
rigid plug retainer surrounds and radially compresses at least part
of a length of the elastic plug.
20. A method of introducing a catheter into a blood vessel
comprising the steps of: gaining access to the blood vessel by
means of a needle comprising a proximal end and a distal end
comprising a sharp tip, said needle being disposed longitudinally
within a catheter having a proximal end connected to a housing and
a distal end, such that the sharp tip of the needle projects beyond
the distal end of the catheter and at least part of the proximal
end of the needle is disposed within a slit in a spring-biased
septum that is disposed within and substantially blocks an internal
channel through the housing, said spring-biased septum comprising
an elastic plug and a biasing element; introducing the distal end
of the catheter into the blood vessel; and withdrawing the needle
from the blood vessel without removing the distal end of the
catheter from the blood vessel by pulling on a finger grip attached
to the proximal end of the needle such that the needle is withdrawn
through the spring-biased septum.
21. A method of introducing a catheter into a blood vessel as
defined in claim 20, wherein the elastic plug comprises an annular
groove and the biasing element is disposed within said annular
groove.
22. A method of introducing a catheter into a blood vessel
comprising the steps of: gaining access to the blood vessel by
means of a needle comprising a proximal end and a distal end
comprising a sharp tip, said needle being disposed longitudinally
within a catheter having a proximal end in fluid connection with a
housing and a distal end, such that the sharp tip of the needle
projects beyond the distal end of the catheter and the proximal end
of the needle is attached to a wire, at least part of said wire
being disposed within a slit in a spring-biased septum that is
disposed within and substantially blocks an internal channel
through the housing, said spring-biased septum comprising an
elastic plug and a biasing element; introducing the distal end of
the catheter into the blood vessel; and withdrawing the needle from
the blood vessel without removing the catheter from the blood
vessel by pulling on a finger grip attached to the wire such that
the wire and the needle are withdrawn through the spring-biased
septum.
23. A method of introducing a catheter into a blood vessel as
defined in claim 22, wherein the elastic plug comprises an annular
groove and the biasing element is disposed within said annular
groove.
Description
BACKGROUND
[0001] 1. The Field of the Invention
[0002] The present invention is related to a blood seal having a
spring-biased septum for use in connection with various medical
devices. More specifically, the present invention relates to a
blood seal having a spring-biased septum which is particularly
adaptable for use in sealing a vascular access device immediately
following placement of a catheter into a blood vessel of a
patient.
[0003] 2. Technical Background
[0004] During medical treatment, patients often require medication,
blood, or fluids. The most efficient way of administering these
substances is by depositing them directly into a patient's blood
stream where the circulatory system quickly directs the substance
to the target tissue or organ. Thus, vascular catheters for
infusion of fluids, blood, and medications into patients are among
the most commonly used medical devices. The insertion of a vascular
catheter allows repeated or continuous access to the circulatory
system of a patient. Vascular catheters are generally inserted into
the extremities of a patient and fluids, blood, and medications are
introduced to the patient through such catheters.
[0005] Catheters of this type are generally inserted into a vein or
artery by means of an introducer needle. In one common
configuration, the catheter is initially placed over the needle.
The needle, with the catheter located over the needle, is inserted
into the patient until the desired vein or artery is located. Once
the needle and catheter are properly located in the vein or artery,
the needle is withdrawn from the catheter and discarded. The
catheter remains in the vein or artery to provide access to the
circulatory system of the patient without repeated needle
punctures.
[0006] When the catheter insertion and placement steps have been
concluded, one end of a tube (or "tubing set") is generally
attached to the proximal end of the catheter. The opposite end of
the tube is attached to a source of fluid and medication. The
source of fluid is typically a bottle or bag containing the fluid
required for treatment of the patient. Once attachment of the
catheter to the fluid source is completed, fluids are allowed to
flow through the tubing, into the catheter, and ultimately into the
patient. In most situations, fluids flow through the tubing set and
into the patient by means of gravity feed or using a standard
infusion pump.
[0007] It will be appreciated that it is important to minimize the
leakage of blood to the outside environment during each of the
steps described above. Blood leakage can expose medical personnel
and others to blood-borne diseases such as AIDS and hepatitis.
Blood leakage can contaminate equipment and supplies in the
treatment area. Blood leakage may also cause unnecessary alarm on
the part of the patient and other observers. Thus, it is important
to prevent or minimize blood leakage in order to maintain safety,
aesthetics, and to retain equipment and supplies in good working
order.
[0008] The placement and use of catheters of the type described
above involve the potential for blood leakage. For example, the
removal of the introducer needle once the catheter is in place
generally results in a short period of time during which blood may
flow out of the catheter to the surrounding environment.
[0009] Attempts have been made to deal with the problem of blood
leakage during the placement of catheters. Many of these solutions
employ latex or polyisoprene barriers that restrict blood flow.
Such a barrier is situated so that after venipuncture and
introduction of the catheter into the blood vessel of a patient,
the introducer needle is withdrawn through the barrier or plug.
Unfortunately, most polymers, including those used in blood
barriers, tend to take a set over time, especially if an object
such as a needle, wire, or cannula remains in the plug for a
prolonged period before use. As a result, when the needle is
withdrawn through the barrier, the hole left by the needle may fail
to reseal, allowing blood to leak from the device.
[0010] Other attempts to deal with the problem of blood leakage
typically involve devices that are expensive and complex to
operate. For example, one such device employs a relatively complex
valve mechanism connected to the proximal end of the catheter which
opens when a needle is inserted and then closes when the needle is
removed. The valve then opens again when the tubing set is attached
to the catheter. This device requires a mechanism for repeated
opening and closing of the valve, as well as other collateral
structures which facilitate operation of the device. These
relatively complex structures complicate the device and add to its
cost. In addition, the valve device is designed to remain in place
after the tubing set is attached. This increases the potential for
irritation and discomfort to the patient. Such devices are also too
expensive for wide use in developing countries, where the problem
of HIV infection is growing and the need for cost-effective
solutions is great.
[0011] Accordingly, it would be an advancement in the art to
provide a device which would control the flow of blood during the
steps surrounding placement and use of a catheter. It would also be
an advancement in the art to provide such a device which is
inexpensive and simple to operate. It would also be an advancement
in the art to provide such a device which could be used without
requiring significant modification of conventional catheters,
needles, tubing sets and the like. Finally, it would be a
significant advancement in the art to provide such a device which
provided the medical professional with more control in performing
the tasks surrounding placement and use of a catheter.
[0012] Such apparatus are disclosed and claimed herein.
BRIEF SUMMARY AND OBJECTS OF THE INVENTION
[0013] The present invention is a blood seal having a spring-biased
septum for preventing the leakage of blood during the placement and
use of vascular catheters and similar devices. In one presently
preferred embodiment, the blood seal has a housing, at least part
of which is substantially cylindrical in configuration. An internal
channel through the housing is provided. A spring-biased septum is
disposed within and substantially blocks the internal channel. In
certain preferred embodiments, the spring-biased septum includes a
formed elastic plug with a pre-slit or pre-molded hole. In certain
preferred embodiments, the elastic plug may be formed of a
biocompatible elastomer such as latex or polyisoprene.
[0014] In certain preferred embodiments, the elastic plug includes
an annular groove in which a biasing element sits. The biasing
element is disposed about the elastic plug and keeps the slit or
hole closed with a predictable force. In certain preferred
embodiments of the present invention, the biasing element is a
C-shaped spring constructed of a metal or metal alloy. In certain
especially preferred embodiments, the biasing element is a C-shaped
spring constructed of spring steel.
[0015] It will be appreciated that the biasing element prevents
blood flow through the hole or slit, while the elastic plug
prevents blood from flowing around the spring-biased septum. In
certain embodiments, the housing may be constructed of a soft
elastomer. In such embodiments, the spring-biased septum may
optionally include a rigid plug retainer that surrounds and
radially compresses at least part of the length of the elastic
plug, thereby preventing leakage between the plug and the housing.
In other embodiments, the housing is constructed of more rigid
material, eliminating the need for a rigid plug retainer.
[0016] In certain preferred embodiments, the blood seal housing is
attached to the catheter during the catheter placement steps. In
such embodiments, the housing forms a portion of a connector to
which syringes and tubing sets may be attached. In other preferred
embodiments, the blood seal housing is distinct from but attached
to a connector.
[0017] The blood seal of the present invention provides a
self-closing seal through which an object such as a needle, wire,
or cannula may be moved. In certain preferred embodiments, the
blood seal allows removal of an introducer needle from a vascular
access device. In such embodiments, a portion of the introducer
needle is disposed within the slit or hole in the elastic plug.
After venipuncture and the introduction of the catheter into the
patient's blood vessel, the user withdraws the needle through the
blood seal by pulling on a finger grip. After the needle is
withdrawn, the biasing element squeezes the elastic plug, closing
the hole or slit.
[0018] In other preferred embodiments, the introducer needle is
attached to a wire, a portion of which is disposed within the slit
or hole in the elastic plug. After proper placement of the
catheter, the user withdraws the wire and the needle through the
blood seal by pulling a finger grip. As described above, the
biasing element forces the hole or slit closed after withdrawal of
the wire and needle.
[0019] From the foregoing, it will be appreciated that a
spring-biased septum may be used anytime a needle, cannula, wire,
or other similar object must pass through a seal. The present
invention is especially useful in controlling blood leakage during
the placement and use of vascular catheters. Thus, the problems
related to blood leakage to the ambient environment are
substantially reduced. The present invention also provides a device
that is simple and inexpensive to operate, and may be used without
significant modification of conventional catheters and tubing
sets.
[0020] These and other objects and advantages of the invention will
become apparent upon reading the following detailed description and
appended claims, and upon reference to the accompanying
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] In order to more fully understand the manner in which the
above-recited advantages and objects of the invention are obtained,
a more particular description of the invention briefly described
above will be rendered by reference to specific embodiments thereof
which are illustrated in the appended drawings. Please take note
that the embodiments illustrated in the drawings are merely
illustrative.
[0022] FIG. 1 is a perspective view of one embodiment of a vascular
access device incorporating the blood seal having a spring-biased
septum of the present invention.
[0023] FIG. 2 is a perspective view of the spring-biased septum
after the needle has been withdrawn.
[0024] FIG. 3 is a cross-sectional view taken along line 3-3 of
FIG. 2.
[0025] FIG. 4 is a cross-sectional view of the spring-biased septum
prior to removal of the needle.
[0026] FIG. 5 is a longitudinal cross-sectional view of the blood
seal prior to removal of the needle.
[0027] FIG. 6 is a partially cut-away plan view of a second
embodiment of a vascular access device incorporating the blood seal
having a spring-biased septum of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0028] The present invention can be best understood by reference to
the drawings where like parts are designated with like numerals
throughout. One embodiment of a vascular access device
incorporating the blood seal having a spring-biased septum of the
present invention is generally designated 10 in FIG. 1. As
mentioned above, the vascular access device 10 allows for the
placement of a catheter in a patient and subsequent removal of the
introducer needle while maintaining a blood seal at the proximal
end of the catheter. This allows a medical professional to
introduce a catheter into a patient's blood vessel and remove the
introducer needle without the need to be concerned about blood
leakage.
[0029] As illustrated in FIG. 1, the vascular access device 10
includes a catheter 12. The catheter 12 has a distal end 14, a
proximal end 16, and an internal lumen 18. A needle 20 having a
sharpened end 22 is slidably mounted within the internal lumen 18
of the catheter 12, such that the sharpened end 22 of the needle
protrudes a short distance beyond the distal end 14 of the catheter
12. The sharpened end 22 allows a medical professional to puncture
the blood vessel of a patient, creating an access site and
facilitating the introduction of the distal end 14 of the catheter
12 into the blood vessel. The distal end 14 of the catheter 12 is
tapered, allowing dilation of the access site as the distal end 14
of the catheter 12 is introduced into the blood vessel.
[0030] The needle includes a distal opening 24, a notch-like
opening 26, and a lumen 30. The lumen 30 permits fluid to flow
between the distal opening 24 and the notch-like opening 26.
[0031] The needle is provided with a proximal end 28 attached to a
finger grip 34. The needle 20 extends coaxially through the
internal lumen 18 of the catheter, passes through a blood seal 40
disposed within a branched connector 42, and is attached to the
finger grip 34, such that after the introduction of at least part
of the catheter 12 into the blood vessel, the needle 20 may be
withdrawn from the access site by pulling the finger grip 34 in the
direction indicated by arrow A, minimizing the risk of injury to
the blood vessel.
[0032] The branched connector 42 includes a housing 44 and an
internal channel 46 through the housing 44. Disposed within and
substantially blocking the internal channel 46 is a spring-biased
septum 50. The housing 44, internal channel 46, and spring-biased
septum 50 form a blood seal.
[0033] FIG. 2 shows a perspective view of the spring-biased septum
50, which includes a dumbbell-shaped elastic plug 52. The elastic
plug 52 may be constructed of a biocompatible elastomer. In certain
preferred embodiments, the elastic plug 52 is constructed of
polyisoprene or latex. The elastic plug 52 has an annular groove 54
in which a biasing element 56 is disposed. In the embodiment shown
in FIGS. 1 and 2, the biasing element 56 is a C-shaped spring. The
biasing element 56 may be constructed of a resilient material. In
certain preferred embodiments, the biasing element 56 is
constructed of a metal or a metal alloy. The biasing element 56
may, for example, be constructed of spring steel.
[0034] The elastic plug 52 also includes a slit 58 through which
the needle 20 passes. It will be appreciated that the slit 58 may
be replaced by any of a number of equivalent elements, such as a
hole or channel through the elastic plug 52. Prior to use, a
portion of the needle 20 is disposed within the slit 58. After the
needle 20 is withdrawn, the slit 58 closes to prevent blood
leakage.
[0035] FIG. 3 shows a cross sectional view of the spring-biased
septum 50 after the needle has been withdrawn. The elastic plug 52,
biasing element 56, and slit 58 are illustrated. From this view, it
will be appreciated that the biasing element 56 compresses a
portion of the elastic plug 52, keeping the slit 58 closed with a
predictable force.
[0036] FIG. 4 shows a cross-sectional view of the spring-biased
septum 50 prior to removal of the needle 20. The needle 20, elastic
plug 52, biasing element 56, and slit 58 are illustrated. This
Figure illustrates the manner in which the needle 20 penetrates the
spring-biased septum 50 through the slit 58.
[0037] FIG. 5 shows a longitudinal cross-sectional view of the
blood seal 40 prior to withdrawal of the needle 20 through the
spring-biased septum 50. The housing 44, internal channel 46, and
spring-biased septum 50, which includes the elastic plug 52, the
annular groove 54, and the biasing element 56 are illustrated.
[0038] Returning to FIG. 1, the vascular access device 10 includes
means for attaching conventional tubing sets and syringes. The
branched connector 42 is attached to a tube 60, which is attached
to a female adaptor 62. The female adaptor 62 permits removable
attachment of syringes or other connectors. The embodiment of the
vascular access device 10 shown in FIG. 1 also includes an
injection piece 64 attached to the female adaptor 62. When the
distal end 14 of the catheter 12 is in the blood vessel of a
patient, medications may be injected via the injection piece 64. It
will be appreciated that other attachment means, such as threaded
connectors and luer locks, are well known in the art and may be
used with the present invention.
[0039] In operation, the user grips the vascular access device 10
by the branched connector 42 (shown in FIG. 1) and punctures the
blood vessel of a patient with the sharpened end 22 of the needle
20, facilitating the introduction of at least part of the distal
end 14 of the catheter 12 into the patient's blood vessel. The
notch-like opening 26 allows the user to monitor the placement of
the needle 20. Blood flashback through the distal opening 24, into
the lumen 30 of the needle 20, and out the notch-like opening 26
verifies blood vessel puncture.
[0040] After proper placement of the needle 20 and the distal end
14 of the catheter 12 into the patient's blood vessel, the needle
20 is withdrawn to prevent inadvertent damage to the blood vessel.
The user withdraws the needle 20 by pulling on the finger grip 34,
which is attached to the proximal end 28 of the needle 20, in the
direction of arrow A. The sharp tip 22 of the needle 20 is
withdrawn through the spring-biased septum 50. The biasing element
56 forces the slit 58 to close, preventing blood leakage. The user
may then discard needle 20, which is still attached to finger grip
34, in a container designed for disposal of blood-contaminated
sharps or as otherwise might be appropriate.
[0041] Removal of the needle 20 leaves the distal end 14 of the
catheter 12 in the patient's blood vessel. The user may then
introduce a source of fluids or inject medications via the female
adaptor 62 or injection piece 64. The means of connecting sources
of fluids and medications to the types of connector shown are well
known in the art. Fluids and medications flow into the tube 60,
through the branched connector 42 and catheter 12, and into the
blood vessel of the patient.
[0042] A second embodiment of a vascular access device
incorporating the spring-biased septum of the present invention is
generally designated 110 in FIG. 6. The vascular access device 110
includes a catheter 112 having a distal end 114 and a proximal end
116. A needle 120 having a sharpened end 122 is slidably mounted
within the catheter 112, such that the sharpened end 122 of the
needle protrudes a short distance beyond the distal end 114 of the
catheter 112. It will be appreciated that the needle 120 may
incorporate openings as described above that permit the user to
monitor placement of the needle 120. The sharpened end 122 allows a
medical professional to puncture the blood vessel of a patient,
creating an access site and facilitating the introduction of the
distal end 114 of the catheter 112 into the blood vessel. The
distal end 114 of the catheter 112 is tapered, allowing dilation of
the access site as the distal end 114 of the catheter 112 is
introduced into the blood vessel.
[0043] The needle 120 is provided with a proximal end 128 attached
to a wire 132. At the opposite end of the wire 132 from the
proximal end 128 of the needle 120 is a finger grip 134, such that
after the introduction of at least part of the catheter 112 into
the blood vessel, the needle 120 may be withdrawn from the access
site by pulling the finger grip 134, minimizing the risk of injury
to the blood vessel. The needle is withdrawn through a tube 136 and
a branched connector 142, through a blood seal 140, and into a
protective sheath 160. The protective sheath 160 may be as
described in U.S. Pat. No. 5,304,136 and functions to protect the
user from an inadvertent needle stick.
[0044] The blood seal 140 includes a housing 144 and an internal
channel 146. A spring-biased septum 150 is disposed within and
substantially blocks the internal channel 146. The spring-biased
septum 150 is formed as described above and includes an elastic
plug 152 with an annular groove 154. A biasing element 156 is
disposed within the annular groove 154. The elastic plug includes a
slit 158. Prior to use, a portion of the wire 132 is disposed
within the slit 158. After placement of a portion of the catheter
112 into the blood vessel of the patient, the wire 132 and needle
120 are withdrawn through the slit 158. The biasing element 156
compresses a portion of the elastic plug 152, closing the slit 158
and preventing blood leakage.
[0045] The vascular access device 110 includes means for attaching
conventional tubing sets and syringes. The branched connector 142
includes a female adaptor 162, permitting removable attachment of
syringes of other connectors. It will be appreciated that other
attachment means, such as threaded connectors and luer locks, are
well known in the art and may be used with the present
invention.
[0046] In operation, the user punctures the blood vessel of a
patient with the sharpened end 122 of the needle 120, facilitating
the introduction of at least part of the distal end 114 of the
catheter 112 into the patient's blood vessel. After proper
placement of the needle 120 and the distal end 114 of the catheter
112 the needle 120 is withdrawn to prevent inadvertent damage to
the blood vessel. The user withdraws the needle 120 by pulling on
the finger grip 134, which is attached to the wire 132, which, in
turn is attached to the proximal end 128 of the needle 120. The
needle 120 is withdrawn from the catheter 112, through the tube 136
and branched connector 142, through the blood seal 140, and into
the protective sheath 160. The user may then discard the protective
sheath 160.
[0047] Removal of the needle 120 leaves the distal end 114 of the
catheter 112 in the patient's blood vessel. The user may then
introduce a source of fluids or inject medications via the female
adaptor 162. Fluids and medications flow through the branched
connector 142, tube 136, and catheter 112 and into the blood vessel
of the patient.
[0048] In summary, the present invention provides a device which
controls the flow of blood during the steps involved in the
insertion of a catheter. The present invention provides a device
which is inexpensive and simple to operate. The blood seal of the
present invention can also be used without significant modification
of conventional catheters, needles, tubing sets and the like.
[0049] The invention may be embodied in other specific forms
without departing from its spirit or essential characteristics. The
described embodiments are to be considered in all respects only as
illustrative and not restrictive. The scope of the invention is,
therefore, indicated by the appended claims rather than by the
foregoing description. All changes which come within the meaning
and range of equivalency of the claims are to be embraced within
their scope.
* * * * *