Syringe needle abstract
A syringe needle thimble cap and its method of use is shown such
that the thimble cap has a porous plastic, hydrophilic core captured
within a cylindrical cap member for use with an arterial blood gas
syringe barrel and needle assembly. The syringe needle thimble cap
has a generally thimble-shaped cap with a proximal opening. The
porous plastic core material is positioned within the thimble cap
distally to the proximal opening, and the core material is held
in place by an inwardly extending ring to prevent its removal. An
open or hollow space is created distally to the porous material
which is otherwise bounded by the interior surfaces of the thimble
cap.
Syringe needle claims
We claim:
1. A syringe needle thimble cap for purging air from a hypodermic
needle and syringe comprising:
a cylindrical member having a closed end and an open end;
an absorbent core material affixed within said cylindrical member,
the core filling only a portion of said tubular member such that
an open space exists between the core and the closed end, the core
being pierceable by the hypodermic needle to allow for the purging
of air from the needle and syringe, the core material being hydrophilic
such that it absorbs any liquid ejected from the hypodermic needle
and syringe while allowing air to escape from the open space within
the tubular member to the outside atmosphere.
2. A syringe needle thimble cap of claim 1 wherein the hydrophilic
core is manufactured out of a porous plastic material which allows
for the passage of air but not liquid.
3. A syringe needle thimble cap of claim 1 wherein the hydrophilic
core is manufactured from a porous plastic material which allows
for the passage of air while absorbing any liquid.
4. A syringe needle thimble cap of claim 1 wherein the cylindrical
member is provided with a smooth cylindrical outside surface.
5. A syringe needle thimble cap of claim 1 wherein the cylindrical
member has an exterior surface provided with a plurality of flats
to prevent the cap from rolling when placed on its side.
6. A syringe needle thimble cap of claim 1 wherein said cylindrical
member is made from a visually clear material to allow an intended
user to observe when all of the air has been purged from the hypodermic
needle and syringe.
7. A syringe needle thimble cap of claim 1 wherein the cylindrical
member has an inwardly radially extending ring such that said absorbent
core material is inserted within said cylindrical member so that
said ring compresses against said core material to affix said core
material in position within the cylindrical member.
8. A syringe needle thimble cap of claim 1 wherein the open end
of said cylindrical member has an inwardly radially extending rim
partially closing such open end.
9. A syringe needle thimble cap of claim 1 wherein the closed
end of the cylindrical member has a relatively flat outer surface
to allow said thimble cap to be easily placed on a flat surface
with said open end facing in an upwardly direction.
10. A method for quickly purging air from a hypodermic syringe
and needle assembly containing a blood sample, comprising the steps
of:
providing a hypodermic syringe and needle assembly containing a
blood sample, the hypodermic syringe having a barrel and plunger;
inserting the needle end of the hypodermic syringe and needle assembly
into a syringe needle thimble cap having a tubular member with a
closed end and an open end, the thimble cap being provided with
an absorbent core material affixed within the tubular member adjacent
its open end such that an open space exists within the tubular member
between the core material and the closed end of the tubular member,
the core material being pierceable by the tip of the hypodermic
needle;
inverting the syringe barrel and needle assembly with thimble cap
impaled thereon such that the needle assembly is pointing in an
upwardly direction; advancing the plunger within the syringe to
expel any air and excess blood within the syringe barrel and needle
assembly into the thimble cap;
removing the needle assembly with thimble cap impaled thereon from
the syringe barrel; and
disposing of the needle assembly and thimble cap into a protective
container.
11. The method of claim 10 wherein the inserting step includes
the step of inserting the tip of the needle through the core material
so that the tip of said needle extends into the interior open space
within the thimble cap.
12. The method of claim 11 wherein the blood sample is an arterial
blood gas sample.
13. The method of claim 10 wherein the advancing step includes
the step of advancing the plunger within the syringe to expel air
and blood from within the syringe barrel and needle assembly until
observing a visual indication of blood being absorbed by the absorbent
core material of the thimble cap.
14. A method for quickly purging air from a hypodermic syringe
and needle assembly containing an arterial blood gas sample taken
from a human patient by a medical technician, the syringe having
a barrel and plunger, the needle assembly having a sharp needle
tip, comprising the steps of:
inserting the needle tip of the hypodermic syringe and needle assembly
into an artery of a human patient and obtaining an arterial blood
gas sample;
removing the syringe and needle assembly from the injection site
by the medical technician with one hand while depressing the injection
site with the fingers of the other hand;
inserting the needle end of the syringe and needle assembly into
a syringe needle thimble cap by the use of one hand of the medical
technician while continuing to depress the injection site with the
other hand, the thimble cap having a tubular member with a closed
end and an open end, the thimble cap being provided with an absorbent
core material affixed within the tubular member adjacent its open
end such that a hollow space exists within the tubular member between
the core material and closed end of the tubular member, the core
material being pierceable by the hypodermic needle;
inverting the syringe barrel and needle assembly with thimble cap
impaled thereon so that the thimble cap is above the syringe barrel
by the use of one hand of the medical technician while continuing
to depress the injection site with the technician's other hand;
advancing the plunger within the syringe to expel any air and excess
blood from within the syringe barrel and needle assembly into the
hollow space of the thimble cap by the use of one hand of the medical
technician while continuing to depress the injection site with the
technician's other hand;
setting the syringe barrel and needle assembly aside while cleaning
and bandaging the injection site;
removing the needle assembly with thimble cap impaled thereon from
the syringe barrel and disposing of the needle assembly and thimble
cap into a protective container; and
transporting the blood filled syringe barrel to the lab for proper
analysis of the patient's blood gas levels.
15. The method of claim 14 wherein the inserting step includes
the step of the core material being pierceable by the hypodermic
needle so that the tip of said needle extends into the hollow space
within the thimble cap.
16. The method of claim 14 wherein the step of removing the needle
assembly with thimble cap impaled thereon from the syringe barrel
is performed immediately before the step of setting the syringe
barrel and needle assembly aside while cleaning and bandaging the
injection site.
17. The method of claim 14 wherein the advancing step includes
the step of advancing the plunger within the barrel to expel air
and blood from within the syringe barrel and needle assembly until
observing a visual indication of blood being absorbed into the core
material of the thimble cap.
18. A method for quickly purging air from a hypodermic syringe
and needle assembly containing an arterial blood gas sample by a
medical technician using only one hand, the syringe having a barrel
and plunger, the needle assembly having a sharp needle tip, comprising
the steps of:
providing a syringe containing an arterial blood gas sample;
inserting the needle end of the hypodermic syringe and needle assembly
into a syringe needle thimble cap having a tubular member having
a closed end and an open end, the thimble cap being provided with
an absorbent core material affixed within the tubular member adjacent
its open end such that an open space exists within the tubular member
between the core material and the closed end thereof, the thimble
cap resting on an adjoining surface with its open end facing upwards,
the core material being pierceable by the needle so that the needle
tip extends into the open interior space within the thimble cap;
inverting the syringe barrel and needle assembly with the thimble
cap impaled thereon such that the needle assembly is pointing in
an upwardly direction; and
advancing the plunger within the syringe to expel any air and excess
blood within the syringe barrel and needle assembly into the thimble
cap.
19. The method of claim 18 wherein the advancing step includes
the step of advancing the plunger within the syringe barrel to expel
any air and blood from within the syringe barrel and needle assembly
until observing a visual indication of blood being absorbed into
the core material of the thimble cap.
Syringe needle description
FIELD OF THE INVENTION
This invention relates generally to an apparatus for protecting
the sharp needle tip of a medical syringe, and more particularly
to an apparatus and method for catching fluid purged from the needle
of a syringe while capturing the tip of the needle for safe disposal
of the needle.
BACKGROUND OF THE INVENTION
The use of syringes for the hypodermic withdrawal of blood from
a patient's body through a hollow needle detachedly forming a part
of a syringe is commonplace in modern medicine. One reason to take
blood from a patient is to obtain an arterial blood gas sample.
Air is almost always included within the syringe barrel or needle
after filling the syringe barrel with blood. For example, aspiration
of a sample through a needle or the incomplete filling of a syringe
may draw air into the syringe. There are many instances in which
such air can contaminate an arterial blood gas sample. In taking
an arterial blood gas sample, the purpose is to evaluate the patient's
blood gas levels (i.e., carbon dioxide and oxygen) or to evaluate
other variables which depend upon blood gas levels (i.e., pH levels),
therefore the introduction of air into the sample would serve to
alter the true concentrations in the blood and cause subsequent
analysis of data to be misleading. It is therefore desirable to
remove any air from the blood sample as quickly as possible after
removal of the blood from the patient's body.
Accordingly, one technique for removing air from a freshly-filled
syringe is to tilt the syringe upward so that the air bubbles rise
to the top of the syringe barrel and the plunger is advanced into
the barrel to purge the air through the needle tip. Although this
technique works well in removing air from the syringe body and needle,
it may also cause some blood to be expelled from the tip of the
needle. The blood may be expelled either if the plunger is pushed
too aggressively or if blood is trapped by capillarity in the uppermost
portion of the luer, needle hub or needle.
Typically, the purged air and liquid spray from the needle would
be simply squirted into the air or into a pad of gauze material.
However, with the great concerns today about the transmission of
various diseases such as AIDS and hepatitis, great care must be
taken in the removal of such blood spray from an arterial blood
gas sample and further in the handling and disposal of hypodermic
syringe needles used with such syringe systems.
Many prior art patents dealing with the blood sample air-contamination
problem concentrated on expelling contaminating air from the syringe
while the syringe was being filled with the patient's blood. U.S.
Pat. Nos. 3978846 and 4340067 disclose devices incorporating
self-sealing hydrophilic filters into the body of the syringe. When
dry, a self-sealing type hydrophilic filter allows air to pass through
it and out of the syringe. The syringe-filter system fills with
blood because a pressure differential between the luer opening and
the filter is created by the patient's arterial pressure. This air
pressure differential helps force air through the filter and out
of the syringe. When all of the air is expelled, the leading edge
of the blood contacts the filter. When wetted by the blood, the
self-sealing nature of the filter causes it to expand and prohibit
passage of both air and liquid. However, the utility of these type
of self-sealing hydrophilic systems does not extend to post filling
contaminations because the already wetted filter will no longer
pass air and so it can not be utilized to purge any remaining air
or air introduced at later times. Also, such filters have not always
self-sealed in the proper manner thereby allowing blood to seep
out of the plunger end of the syringe body possibly causing dangerous
contamination of medical personnel.
U.S. Pat. Nos. 4769026 and 4775376 to Strung disclose syringe
purging devices that address the problems of post filling contamination.
These devices utilize separate containers which are either airtight
or are equipped with hydrophobic filters. Hydrophobic filters allow
for the passage of air but not liquid. Various embodiments of these
patents also include a deactivating substance for neutralizing the
hazardous fluids which are to be injected into the container. In
use, the container and syringe are attached in an airtight fit,
air and blood from the syringe are injected into the separate container
by advancing the syringe plunger until the air has been evacuated
from the syringe. However, such a device is overly complicated for
the uses intended for the present invention. An airtight chamber
is neither necessary nor desirable for the present invention. Furthermore,
a deactivating substance involves an unnecessary complication and
expense.
U.S. Pat. No. 5125415 to Bell discloses a syringe tip cap utilizing
a self-sealing hydrophilic filter in a separate chamber for allowing
for the purging of air from the syringe body. However, the syringe
tip cap disclosed in Bell can be used only after the needle and
hub assembly has been removed from the syringe body. Typically,
the sequence of events by a nurse technician or other medical personnel
in taking an arterial blood gas sample would be as follows. First,
the technician would remove the blood filled needle and syringe
barrel assembly from the patient's arm or any other injection site
with one hand while depressing the injection site with the fingers
of their other or second hand. The needle and syringe barrel assembly
is set aside while the patient's arm is properly bandaged. Next,
the technician would remove the needle and needle hub from the syringe
barrel and properly dispose of them into a protective sharps container.
Then, the syringe tip cap would be attached to the distal end of
the syringe barrel, the syringe barrel would be held in an upside
down position or held with the distal end pointing upwardly while
the technician advances the plunger to purge any air bubbles with
attendant liquid blood spray out of the syringe barrel and into
the absorbent filter of the syringe tip cap.
The above sequence of events is undesirable in that the air bubbles
were allowed to remain in the blood sample for a significant period
of time while the technician was bandaging the patient's arms and
removing and disposing of the needle and hub assembly into a protective
sharps container. It is possible that the blood sample would be
significantly contaminated by the air existing within the blood
sample so as to provide erroneous blood gas levels such that subsequent
analysis of this data to be misleading.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a protective
cover for a previously used syringe needle which substantially aids
in avoidance of accidental needle sticks to medical personnel using
the syringe assembly.
It is a further object of the present invention to provide a syringe
needle thimble cap for placement over a previously used syringe
needle to allow air bubbles and any attendant liquid and/or blood
spray to be injected into the thimble cap to prevent external contamination
of the surgical field or to medical personnel.
It is another object of the present invention to provide a syringe
needle thimble cap for use with an arterial blood gas sample syringe
barrel and needle assembly so that any air bubbles within the blood
filled syringe barrel may be purged into the syringe needle thimble
cap without external contamination of the surgical field or to medical
personnel, and to protect the needle tip to prevent accidental needle
sticks of medical personnel.
It is another object of the present invention to provide a syringe
needle thimble cap that can be installed on a syringe barrel and
needle and utilized to purge any air bubbles out of the syringe
body by use of only one hand of a medical technician using such
syringe barrel and needle assembly.
It is yet another object of the present invention to provide a
syringe needle thimble cap for use with an arterial blood gas sample
syringe barrel and needle assembly which can be installed on the
needle assembly via the use by one hand of a medical technician
such that the syringe barrel may be inverted and any air bubbles
evacuated therefrom without such technician removing their other
hand from the injection site on the patient's body.
These and other objects are realized in the presently preferred
embodiment of a syringe needle thimble cap having a porous plastic,
hydrophilic-type core captured within its boundaries for use with
a standard arterial blood gas syringe barrel and needle assembly.
The syringe needle thimble cap includes a generally thimble-shaped
rigid plastic cap having a proximal opening. It is preferable for
the plastic material of the rigid cap to be clear or substantially
clear to allow a medical technician to observe the needle point
within the thimble cap. The porous plastic core material is positioned
within the thimble cap distally to the proximal opening, and the
core material is held in place by an inwardly extending ring or
lip to prevent the removal of the porous plastic material. The core
material is slightly compressible to allow it to be positioned within
the thimble cap such that the inwardly extending ring compresses
the core provide a snug fit. Additionally, the porous plastic material
occupies only a portion of the space within the thimble cap such
that an open or hollow space is created distally to the porous material
and otherwise the open space is bounded by the interior surfaces
of the thimble cap.
The proximal opening of the thimble cap allows for the introduction
of the needle point and shaft of the needle assembly into the porous
plastic material of the thimble cap. The needle point is pushed
completely through the porous plastic material by the medical technician
which gives the technician a feel as to when the needle point has
been penetrated through the porous plastic material sufficiently
so that its needle point is positioned within the open space of
the thimble cap. The plunger of the syringe barrel may now be advanced
while holding the syringe barrel and needle assembly with thimble
cap affixed thereto in an inverted position such that the needle
point is pointing in an upwardly direction. When the air bubbles
are expelled into the open space of the thimble cap, a small amount
of blood is also expelled into the thimble cap which is absorbed
by the porous plastic material. Thus, when the syringe needle thimble
cap of the present invention is placed over the syringe needle as
discussed above, the thimble cap protects the medical technician
from needle stick injuries and absorbs any potentially hazardous
blood that is expelled from the syringe barrel while letting any
air pass through the porous material. Furthermore, when the red
blood spray is injected into the core material this provides the
medical technician with a visual indication of when all the air
has been expunged from the syringe barrel and needle assembly.
According to another aspect of the present invention, an improved
method for quickly purging air bubbles from a syringe containing
a patient's arterial blood gas blood sample so that such air bubbles
do not contaminate the results obtained from later analysis of such
blood sample is also disclosed. The method includes the steps of:
withdrawing a filled arterial blood gas sample syringe barrel and
needle assembly from a patient's arm with one hand while depressing
the injection site with the other hand of a medical technician taking
a patient's blood sample; stabbing the needle point into a syringe
needle thimble cap of the present invention and inverting the syringe
barrel, needle assembly and attached thimble cap so that the needle
assembly is pointing in an upwardly direction and any air bubbles
contained within the syringe barrel have gravitated towards the
needle assembly; manually operating the syringe to purge air and/or
excess liquid blood from the syringe barrel and needle assembly
while still depressing the injection site on the patient's arm or
other injection site with one hand; retaining any ejected liquid
blood within the thimble cap; setting the syringe barrel and needle
assembly aside while properly bandaging the patient's injection
site; removing the needle assembly with protective thimble cap attached
over the end of the needle point from the syringe barrel containing
the arterial blood gas sample; and discarding the needle assembly
with thimble cap into a protective sharps container.
Alternatively, the method for purging a syringe barrel may include
setting the blood filled syringe barrel and needle assembly aside
immediately after withdrawing the syringe barrel and needle assembly
from the patient's arm and stabbing the needle point into the thimble
cap so that the medical technician can properly bandage the patient's
arm, and then allowing the technician to follow through with the
steps of purging the air bubbles from the syringe barrel as discussed
above. In either method, the medical technician would then cap the
syringe barrel and send the blood sample to the lab for analysis.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partially exploded view of a standard syringe barrel,
plunger and needle assembly wherein the needle assembly is shown
separated from the syringe barrel.
FIG. 2 is a cross-sectional view of the syringe needle thimble
cap of the present invention.
FIG. 3 is a plan view of the syringe needle thimble cap of FIG.
2 attached to the needle assembly of the syringe body shown in FIG.
1 the syringe body and needle assembly shown in the inverted position.
FIG. 4 is a plan view of one embodiment of the syringe needle thimble
cap having a contoured outer configuration.
FIG. 5 is a top view of the syringe needle thimble cap shown in
FIG. 4.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIG. 2 of the drawings, a syringe needle thimble
cap according to the present invention is shown and denominated
by the reference numeral 30. The syringe needle thimble cap 30 is
designed to cooperate with a standard hypodermic syringe 10. As
shown in FIG. 1 syringe 10 includes a syringe barrel 12 fitted
with a plunger 14 slidably received therein so that the inside walls
of the barrel and the outer edge of the plunger produce a tight
fit around the circumference of the plunger 14. The syringe barrel
12 is further provided with a needle assembly 16 having a hollow
needle 18 with distal tip portion 20 and a needle hub 22. The hollow
needle 18 is affixed within the needle hub 22. The needle hub 22
is provided with a female-type luer connector 24 which is designed
to connect to a male-type luer connector 26 provided on the end
of the syringe barrel 12. The hypodermic syringe 10 shown in the
drawings is for illustrative purposes only and the syringe needle
tip cap of the present invention could be used with any type of
hypodermic syringe currently on the market.
Referring back to FIG. 2 the syringe needle tip cap 30 is shown
having a tubular body 32 with a closed end 34. The other end 36
is open and is provided with a radially inwardly extending rim 38.
The interior surface of the tubular body 32 is provided with an
inwardly extending ring or lip 39. A hydrophilic absorbent core
40 of a porous plastic material is provided within the tubular body
32 abutting the ring 39 such that the ring prevents the core 40
from being pulled out of the tubular body 32. The core 40 is compressible
to allow it to be positioned within the body 32 such that the inwardly
extending ring 39 compresses the core 40 to provide a snug fit within
the thimble cap. Obviously, the core 40 can be held in place within
the thimble cap in various ways such as simply a friction fit, or
said ring 39 could be non-continuous so as to provide a plurality
of tabs (not shown) extending inwardly against the side of the core
40. Furthermore, core material 40 could be placed distally past
the ring 39 such that the ring 39 provides a distally facing shoulder
upon which the proximal edge of the core 40 rests.
The core 40 is positioned within the tip cap 30 such that an open
or hollow space 42 exists therein. The inside diameter of the tubular
body 32 is decreased at 44 to prevent the core 40 from being pushed
further into the tubular body 32 to close open space 42. It is preferred
that the tubular body 32 be made of a clear plastic material which
will not react adversely to blood to allow a medical technician
to visualize the placement of the needle point within the thimble
cap and the attending purging of air and any blood spray into the
open space of the tubular member.
The absorbent core 40 may be manufactured out of any absorbent
hydrophilic material such that it has the ability to absorb liquid.
A preferred absorbent material utilizes a porous plastic technology
which focuses on the ability of these materials to provide flow
control for liquids or gases. Controlling the flow of a liquid or
gas through a plastic is a function of pore size and pore volume
and by controlling these variables the hydrophobicity, hydrophilicity
and self-sealing type materials can be obtained. Interflo.RTM. Technologies
of Brooklyn, N.Y. manufactures such porous plastic materials and
for the purposes of the present invention it is preferred that the
material be hydrophilic and not self-sealing when contacted by the
liquid blood. Such a hydrophilic material is desirable so that any
blood spray injected into the open space 42 of the thimble cap 30
will be quickly absorbed into the core material 40 without blocking
any air flow from exiting the thimble cap 30 while depressing plunger
14.
Referring to FIGS. 4 and 5 a preferred embodiment of the thimble
cap 30 is shown having an exterior surface 46 with a plurality of
flats 48 positioned about the circumference of the surface 46. The
flats 48 help prevent the thimble cap 30 from rolling if placed
on its side on a flat surface. Alternatively, the thimble cap 30
could have a smooth exterior surface for ease of manufacturing.
Operation of the syringe thimble cap in accordance with an improved
method for quickly purging air bubbles from a syringe containing
a patient's arterial blood gas blood sample as shown in FIGS. 1-5
will now be described with reference particularly to FIG. 3. The
purpose of the improved method is to provide a syringe needle thimble
cap for use with a standard syringe containing an arterial blood
gas blood sample so that any air bubbles contained within the blood
gas sample can be quickly purged from the syringe and needle assembly
so that such air bubbles do not contaminate the results obtained
from subsequent analysis of the blood sample. The syringe barrel
12 and needle assembly 16 as shown in FIG. 1 is utilized to remove
a patient's blood from the patient's artery. The sharp open end
of the needle assembly 16 is inserted into an artery in a patient's
arm (not shown) or other injection site on the body by a qualified
medical technician. The plunger 14 which had previously been inserted
entirely into the syringe barrel 12 is forced back by arterial pressure
or withdrawn to draw the patient's arterial blood into the syringe
barrel 12. The syringe barrel 12 and needle assembly 16 is then
removed by the medical technician from the patient's arm with one
hand while depressing the injection site on the patient's arm or
other injection site with the technician's other hand.
As is almost always the case, air will also be contained with the
syringe barrel 12. In that event, the air contained within the syringe
barrel 12 and needle assembly 16 must be purged as quickly as possible
so that such air will not contaminate the blood sample. In particular
reference to the intended purposes of the present invention, the
blood sample is being taken from the patient's artery so that the
patient's arterial blood gas levels can be evaluated. In taking
an arterial blood gas sample, the purpose is to evaluate the patient's
blood gas levels (i.e., carbon dioxide and oxygen) or to evaluate
other variables which depend upon blood gas levels (i.e., pH levels,
etc.), therefore the introduction of air into the blood gas sample
for any significant period of time would tend to alter the true
concentrations in the blood and cause subsequent analysis of this
data to be misleading. In an effort to remove such air from the
syringe barrel 12 and needle assembly 16 as quickly as possible,
the syringe needle thimble cap 30 of the present invention is conveniently
utilized as follows.
The thimble cap 30 as shown in FIG. 2 is inverted so that it is
resting with its open end 36 facing upwardly on an adjoining table
(not shown) to the patient and medical technician. After the syringe
barrel 12 and needle assembly 16 are removed from the patient's
arm as discussed above and while the technician is still depressing
the patient's injection site with one hand, the technician stabs
the distal tip 20 of the syringe into and through the core material
40 of the thimble cap 30. The technician then inverts the syringe
barrel and needle assembly with thimble cap attached thereto such
that the assembly is held as shown in FIG. 3. The syringe is then
actuated by forcing its plunger 14 into the syringe barrel 12 with
the needle assembly 16 being in a generally upward direction such
that any air within the barrel 12 and needle assembly 16 is adjacent
to and will be ejected through the needle assembly 16 and needle
18 and into the open space 42 of the thimble cap 30 from the barrel
12. Obviously, some portion of the patient's liquid blood contained
within the syringe barrel 12 and needle assembly 16 will also be
ejected into the open space 42 of the thimble cap 30. The blood
will then be absorbed into the core material 40 to prevent blood
contamination of the surgical field or the medical technician. It
is not necessary or required that the needle tip extend actually
into the open space 42 of the thimble cap 30 prior to depression
of the plunger, however it is preferred to provide maximum protection
to the medical technician and surgical field from blood contamination.
The technician can then set the syringe aside so that the technician
can properly bandage the patient's injection site. The distal needle
tip portion 20 is covered by the thimble cap 30 thereby protecting
the medical technician against an accidental needle stick. When
the technician is finished bandaging the patient's injection site,
the technician can remove by rotation of the needle hub 22 from
the syringe barrel 12 for proper disposal into a sharps container.
A protective cap (not shown) can be twisted over the syringe barrel
luer connector 26 to prevent air from reentering the syringe barrel
12 to possibly contaminate the arterial blood gas sample. The blood
filled syringe barrel 12 may then be transported to the lab for
proper analysis of the patient's blood gas levels as discussed earlier.
An alternate method for quickly purging air bubbles from the syringe
includes changing the steps so that the medical technician stabs
the distal tip 20 of the syringe into and through the absorbent
core material 40 of the thimble cap 30 with one hand while depressing
the injection site with the technician's other hand as discussed
above. However at this point, the technician can set the syringe
aside so that the patient's injection site can be properly bandaged.
The medical technician then would invert the syringe barrel 12 and
needle assembly 16 with thimble cap 30 impaled thereon as shown
in FIG. 3. The syringe plunger 14 could then be depressed into the
syringe barrel 12 to eject any air and some blood spray into the
open space 42 of the thimble cap 30. And, as discussed above, the
liquid blood sprayed into the thimble cap 30 would be absorbed into
the core material 40 so that at no time would the patient's blood
come in contact with the surgical field or the medical technician.
The needle assembly 16 with thimble cap 30 protecting its distal
tip portion 20 can now be removed from the syringe barrel for proper
disposal into a sharps container. A protective cap (not shown) can
be twisted over the luer connector 26 of the syringe barrel to prevent
air from re-entering the syringe barrel and for transportation of
the blood sample to the lab.
The above invention has been described in relation to a hypodermic
syringe used in taking an arterial blood gas sample. However, the
syringe needle thimble cap 30 could be utilized with any liquid
filled syringe where air bubbles might be present and it is desirable
to remove such air bubbles without having the liquid contained within
the syringe be exposed exteriorly to the syringe or present a danger
to any medical personnel either operating or being near the syringe
or patient.
Of course, it should be understood that various other changes and/or
modifications to the preferred embodiment described above or its
method of use will be apparent to those skilled in the art. For
example, the thimble cap 30 could have various shapes and inside
configurations which still allow the thimble cap to absorb any liquid
contaminate while permitting any air to be expelled from the thimble
cap. Furthermore, the applicability of the invention need not be
restricted to procedures involving liquid blood. Obviously, many
types of hazardous liquids may be handled by the syringe needle
thimble cap and its method of use. These and other changes can be
made without departing from the spirit and scope of the invention
and without diminishing its attendant advantages. It is therefore
intended that such changes and modifications be covered by the following
claims. |