U.S. patent application number 12/426822 was filed with the patent office on 2009-08-13 for degassing method and system.
This patent application is currently assigned to Medtronic MiniMed, Inc.. Invention is credited to David G. Powell.
Application Number | 20090204073 12/426822 |
Document ID | / |
Family ID | 34116718 |
Filed Date | 2009-08-13 |
United States Patent
Application |
20090204073 |
Kind Code |
A1 |
Powell; David G. |
August 13, 2009 |
DEGASSING METHOD AND SYSTEM
Abstract
A system and method for degassing a fluid in a syringe
comprising and inserting the fluid into a negative pressure device.
The system may include a holder for holding the syringe; a guide
affixed to the holder; a slide for holding a plunger of the
syringe, the slide being movably attached to the guide; and a
locking mechanism opposite the holder for maintaining a position of
the slide. The fluid degasses when the locking mechanism maintains
the position of the slide. The system may also include a piercing
element adjacent the holder for piercing the syringe. The system
and method may also be used for removing fluid from a negative
pressure device.
Inventors: |
Powell; David G.; (Pasadena,
CA) |
Correspondence
Address: |
FOLEY & LARDNER
555 South Flower Street, SUITE 3500
LOS ANGELES
CA
90071-2411
US
|
Assignee: |
Medtronic MiniMed, Inc.
|
Family ID: |
34116718 |
Appl. No.: |
12/426822 |
Filed: |
April 20, 2009 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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10638086 |
Aug 7, 2003 |
7534225 |
|
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12426822 |
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Current U.S.
Class: |
604/125 |
Current CPC
Class: |
A61M 2005/3123 20130101;
A61M 5/36 20130101; A61M 5/14276 20130101 |
Class at
Publication: |
604/125 |
International
Class: |
A61M 5/31 20060101
A61M005/31 |
Claims
1-25. (canceled)
26. A method for degassing a fluid comprising: inserting a syringe
into a degassing tool; drawing a fluid into the syringe; closing
the syringe; retracting a plunger of the syringe to create a vacuum
in a portion of a barrel of the syringe; locking the plunger using
the degassing tool; expelling gas dissolved in the fluid into the
vacuum in the portion of the syringe; and expelling the gas in the
vacuum out of the syringe.
27. The method of claim 26, wherein the fluid is insulin.
28. The method of claim 26, wherein the syringe is closed with a
stopcock.
29. The method of claim 26, wherein the plunger is disposed in a
slidable portion of the degassing tool.
30. The method of claim 26, wherein expelling gas dissolved in the
fluid into the vacuum in the portion of the syringe comprises
shaking the syringe while the syringe is disposed in the degassing
tool.
31. The method of claim 28, wherein expelling the gas in the vacuum
out of the syringe comprises opening the stopcock.
32. A method for degassing a fluid and inserting the fluid into a
negative pressure device implanted in a patient comprising:
inserting a syringe into a degassing tool; drawing a fluid into the
syringe; closing the syringe; retracting a plunger of the syringe
to create a vacuum in a portion of a barrel of the syringe; locking
the plunger using the degassing tool; expelling gas dissolved in
the fluid into the vacuum in the portion of the syringe; expelling
the gas in the vacuum out of the syringe; inserting the syringe
into the negative pressure device; and opening the syringe.
33. The method of claim 32, wherein the fluid is insulin.
34. The method of claim 32, wherein the plunger is disposed in a
slidable portion of the degassing tool.
35. The method of claim 32, wherein expelling gas dissolved in the
fluid into the vacuum in the portion of the syringe comprises
shaking the syringe while the syringe is disposed in the degassing
tool.
36. The method of claim 32, further comprising piercing a portion
of the barrel of the syringe.
37. The method of claim 36, wherein the portion of the barrel of
the syringe pierced is adjacent the fluid and opposite the
implanted device.
38. The method of claim 36, wherein the barrel of the syringe is
pierced such that no pieces of the barrel dislodge into the
fluid.
39. A method for filling a negative pressure device comprising:
inserting a syringe into a degassing tool; closing the syringe;
retracting a plunger of the syringe to create a vacuum in a portion
of a barrel of the syringe; locking the plunger using the degassing
tool; inserting the syringe into the negative pressure device; and
opening the syringe.
40. The method of claim 39, wherein the syringe is inserted into
the negative pressure device using a needle.
Description
BACKGROUND
[0001] 1. Field of the Invention
[0002] Embodiments of the present invention relate to degassing
methods and systems and, in particular, to methods and systems for
degassing a fluid disposed in a standard syringe and for inserting
a degassed fluid into a negative pressure device, such as, for
example, a pump or other reservoir.
[0003] 2. Description of Related Art
[0004] The use of implantable, fluid-delivering devices in the
treatment of various medical conditions has necessitated requisite
procedures for filling the devices with an appropriate fluid and
removing "stale" fluid from the devices when necessary. Although
the devices themselves, such as, for example, pumps and other
reservoirs, could be surgically removed from a patient every time
the addition or removal of fluid from the device is required, such
an invasive surgical procedure performed multiple times would prove
traumatic and debilitating to the patient. Furthermore, these types
of procedures are time-consuming and expensive.
[0005] Implantable pumps and other fluid-containing reservoirs that
are implanted into the human body typically operate as either a
positive pressure device or a negative pressure device. Negative
pressure devices have the advantage of precluding the fluid
contained in the device from leaking into the body in the event the
integrity of the seals of the device are compromised. Because the
pressure in the pump or reservoir under which the fluid resides is
negative with respect to the body, fluid would normally flow into
the pump or reservoir rather than outward from the device and into
the body should a break in the seals occur. Thus, a negative
pressure device provides an element of safety for the patient,
preventing a large, possibly toxic exposure to the fluid in the
device if the seals of the device become compromised.
[0006] Filling an implanted, negative pressure device has typically
been a two-step procedure. First, the fluid with which the device
is to be filled is degassed. Without proper degassing, gasses that
have been dissolved in the fluid could resurface as bubbles in the
fluid when the fluid reaches the body, a situation that could be
dangerous for the patient. Second, after degassing, the degassed
fluid is inserted into the patient. This is typically done through
the skin using a needle that interfaces with a port on the
device.
[0007] The tools that have been available for the degas and fill
procedure have been inadequate for efficiently accomplishing the
procedure. For example, generally, the implant fluid is drawn into
a syringe and degassed by pulling a vacuum in the syringe; however,
no tool currently exists that that locks the plunger of the syringe
in place once the plunger has been drawn back to create the vacuum.
Thus, rather than being able to use standard, off-the-shelf
syringes, prior art solutions have had to custom-modify parts of
the syringe and use other external parts to lock the plunger of the
syringe in place once a vacuum has been pulled. This type of
solution is time-consuming, expensive and inefficient.
[0008] Also, both positive and negative pressure implant devices
present challenges to the fill (or refill) procedure. In a positive
pressure device, the fluid in the syringe must be at a greater
pressure than the pressure existing in the device. Accordingly, the
syringe used must be able to accommodate a pressure-generating
apparatus to build up a presser in the barrel of the syringe.
[0009] In a negative pressure device, the fluid in the syringe will
generally flow from the syringe to the device, since the pressure
in the syringe is normally greater than the pressure in the device.
However, under certain conditions, the pressure in the syringe may
not be sufficiently greater than the pressure in the device to
force the fluid to flow from the syringe to the device. In this
situation, some type of mechanism must be used to generate enough
pressure against the fluid in the syringe to cause the fluid to
flow from the syringe into the device.
SUMMARY
[0010] It is therefore an object of embodiments of the present
invention to provide a system and method for degassing a fluid in a
syringe. It is a further object of embodiments of the present
invention to provide a system and method for injecting a fluid into
an implanted negative pressure device. It is yet a further object
of embodiments of the present invention to provide a system and
method for removing a fluid from an implanted negative pressure
device.
[0011] A system for degassing a fluid in a syringe may include a
holder for holding the syringe; a guide affixed to the holder; a
slide for holding a plunger of the syringe; and a locking mechanism
opposite the holder for maintaining a position of the slide. The
slide may be movably attached to the guide and the fluid may degas
when the locking mechanism maintains the position of the slide. The
holder may be substantially circular and may accept a barrel of the
syringe. The size of the holder may be adjustable.
[0012] The guide may be a cylindrical post. The guide may include a
first post and a second post. The guide may include a single post.
The slide may rotate about the single post. The slide may include a
first aperture for accepting a plunger of the syringe; a second
aperture adjacent the first aperture; a third aperture on a first
side of the slide for accepting a first post; and a fourth aperture
opposite the third aperture for accepting a second post.
[0013] The slide may also include a first aperture for accepting a
plunger of the syringe; a second aperture adjacent the first
aperture; a third aperture on a first side of the slide for
accepting the first post; and a fourth aperture opposite the third
aperture for accepting the second post. The slide may further
include a latch for engaging the locking mechanism. Also, a size of
the slide may be adjustable.
[0014] The locking mechanism may be spring loaded. Also, the system
may include a piercing element adjacent the holder for piercing the
syringe. The system may further include a lever hingedly attached
to the holder. The piercing element may be affixed to the lever. A
rotational movement of the lever may force the piercing element
into the syringe. The piercing element may be movably attached to
the holder. A force applied to the piercing element may force the
piercing element into the syringe. The piercing element may peel
away a portion of the syringe when the piercing element is forced
into the syringe. The piercing element may pierce the syringe in a
manner that precludes pieces of the syringe from separating from
the syringe.
[0015] A degassing tool for degassing a fluid in a syringe may
include a holder for holding the syringe; a guide affixed to the
holder; a slide for holding and moving a plunger of the syringe;
and a piercing element adjacent the holder for piercing the
syringe. The slide may be movably attached to the guide.
[0016] The piercing element may be affixed to a lever. The lever
being affixed to the holder. A rotational movement of the lever may
force the piercing element into the syringe. The piercing element
may also be movably attached to the holder. A force applied to the
piercing element may the piercing element into the syringe. The
piercing element may pierce the syringe in a manner that precludes
pieces of the syringe from separating from the syringe.
[0017] The degassing tool may also include a locking mechanism
disposed opposite the holder for maintaining a position of the
slide. The locking mechanism may be spring loaded.
[0018] A method for degassing a fluid may include inserting a
syringe into a degassing tool; drawing a fluid into the syringe;
closing the syringe; retracting a plunger of the syringe to create
a vacuum in a portion of a barrel of the syringe; locking the
plunger using the degassing tool; expelling gas dissolved in the
fluid into the vacuum in the portion of the syringe; and expelling
the gas in the vacuum out of the syringe. The fluid may be
insulin.
[0019] The syringe may be closed with a stopcock. The plunger may
be disposed in a slidable portion of the degassing tool.
[0020] Expelling a gas dissolved in the fluid into the vacuum in
the portion of the syringe may include shaking the syringe while
the syringe may be disposed in the degassing tool. Expelling the
gas in the vacuum out of the syringe may include opening the
stopcock.
[0021] A method for degassing a fluid and inserting the fluid into
a negative pressure device implanted in a patient may include
inserting a syringe into a degassing tool; drawing a fluid into the
syringe; closing the syringe; retracting a plunger of the syringe
to create a vacuum in a portion of a barrel of the syringe; locking
the plunger using the degassing tool; expelling gas dissolved in
the fluid into the vacuum in the portion of the syringe; expelling
the gas in the vacuum out of the syringe; inserting the syringe
into the negative pressure device; and opening the syringe. The
fluid may be insulin and the plunger may be disposed in a slidable
portion of the degassing tool.
[0022] Expelling gas dissolved in the fluid into the vacuum in the
portion of the syringe may include shaking the syringe while the
syringe may be disposed in the degassing tool.
[0023] The method may further include piercing a portion of the
barrel of the syringe. The portion of the barrel of the syringe
pierced may be adjacent the fluid and opposite the implanted
device. The barrel of the syringe may be pierced such that no
pieces of the barrel dislodge into the fluid.
[0024] A method for filling a negative pressure device may include
inserting a syringe into a degassing tool; closing the syringe;
retracting a plunger of the syringe to create a vacuum in a portion
of a barrel of the syringe; locking the plunger using the degassing
tool; inserting the syringe into the negative pressure device; and
opening the syringe. Also, the syringe may be inserted into the
negative pressure device using a needle.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] FIG. 1 shows a generalized view of a degassing tool
according to an embodiment of the present invention.
[0026] FIG. 2 shows a generalized view of a degassing tool
according to another embodiment of the present invention.
[0027] FIG. 3 shows a generalized method for using a degassing tool
to degas a fluid and refill a negative pressure reservoir according
to an embodiment of the present invention.
[0028] FIG. 4 shows generalized method for using a degassing tool
to remove fluid from a negative pressure reservoir according to an
embodiment of the present invention.
[0029] FIG. 5 shows a generalized view of a degassing tool
according to another embodiment of the present invention.
[0030] FIG. 6 shows a generalized view of components of the
degassing tool shown in FIG. 5 according to another embodiment of
the present invention.
DETAILED DESCRIPTION
[0031] In the following description of preferred embodiments,
reference is made to the accompanying drawings which form a part
hereof, and in which are shown by way of illustration specific
embodiments in which the invention may be practiced. It is to be
understood that other embodiments may be utilized and structural
changes may be made without departing from the scope of the
preferred embodiments of the present invention.
[0032] Although the following description is directed primarily
toward a degassing system and method, embodiments of the present
invention may be used in a variety of capacities and applications.
For example, embodiments of the present invention may be used for
degassing insulin or other medications. Also, embodiments of the
present invention may be used to insert fluid, such as insulin or
other medications, for example, into an implanted pump for delivery
to patient. Embodiments of the present invention may also be used
to remove fluid from an implanted negative pressure device, such
as, for example, a pump or other reservoir. Generally, embodiments
of the present invention may be adapted for use in any type of
situation that calls for degassing a fluid, inserting the fluid
into an implanted negative pressure device, or removing fluid from
an implanted negative pressure device.
[0033] A degassing tool 10 according to an embodiment of the
present invention is shown in FIG. 1. The degassing tool 10
includes, but it is not limited to, a holder 12 for holding the
barrel of a syringe containing fluid and a slide 16 that accepts a
plunger of the syringe. The slide 16 may be movable along guides 18
that are affixed to the holder 12. The degassing tool 10 may also
include, but is not limited to, a locking mechanism 28 for
attaching to a latch 22 attached to the slide 16 and, thus,
maintaining the slide 16 in a locked position. The locking
mechanism 28 may be attached to a base 26 and may release the latch
22 by depressing a release button 30.
[0034] According to the embodiment of the invention shown in FIG.
1, the degassing tool 10 may also include a lever 14 that is
hingedly or otherwise affixed to the holder 12. Affixed to the
lever 14 is a piercing element 24.
[0035] According to embodiments of the present invention, the
holder 12 may be formed into a variety of sizes and shapes. For
example, the holder 12 may be in the form of a cylinder, a hexagon,
an octagon, or even a square or a rectangle. According to an
embodiment of the present invention, the holder 12 may be a simple
ring.
[0036] In addition, the holder 12 may include a holder aperture 34.
The holder aperture 34 may be sized such that it accepts the
barrels of standard, off-the-shelf syringes that are common in the
industry. The holder 12 may be designed such that a distance is
maintained between the syringe and the plunger adequate to hold
sufficient vacuum for degassing when the plunger is pulled away
from the holder 12 and locked by the locking mechanism 28.
[0037] The slide 16 may also be formed into a variety of the shapes
and sizes. The slide 16 may include a plunger aperture 20 that is
sized to accept the plunger of the syringe that is in the holder
12. The slide 16 may also a include a handle aperture 32. The
handle aperture 32 may be used for leverage when sliding the slide
16 away from the holder 12. For example, a user may insert his or
her fingers into the handle aperture 32 while resting his or her
palm on the base 26 to obtain leverage when pulling the plunger,
which is located in the plunger aperture 20, away from the barrel
of the syringe which is being held by the holder 12.
[0038] The slide 16 may also include guide apertures 21 that accept
the guides 18 and along which the slide 16 may move. The slide
apertures 21 should be sized such that the slide 16 may move freely
along the guides 18, which themselves may be formed, for example,
as circular posts.
[0039] Although in the embodiment of the invention shown in FIG. 1,
the slide 16 has been designed to accommodate two guides 18, the
slide 16 may be designed to accommodate a variety of guide
configurations. For example, according to an embodiment of the
present invention, only one guide may be affixed to the holder 12
and the base 26. The slide 16 may be designed with only one guide
aperture such that the slide is able to move up and down the length
of the guide and may also rotate freely about the guide. In this
configuration, a syringe may be placed into the holder 12 and the
slide may be rotated about the guide to meet the plunger of the
syringe.
[0040] The slide 16 may be designed in a variety of ways. For
example, the slide 16 need not be a rigid member. The slide 16 may
be designed, for example, as a wire that attaches to the plunger of
the syringe.
[0041] The locking mechanism 28 may include any mechanism that can
maintain the slide 16 in a fixed position after the plunger of the
syringe has been pulled away from the holder 12 so that a vacuum
forms within the interior of the syringe barrel. In the embodiment
of the invention shown in FIG. 1, the locking mechanism 28 is a
spring-loaded post that includes an extension 29 for mating with
the latch 22. The latch 22 may include one or more teeth to provide
a variable lock position for the slide 16. To release the latch 22
from the locking mechanism 28, a release button 30 may be depressed
to move the locking mechanism 28 away from the teeth of the latch
22. According to another embodiment of the present invention, the
locking mechanism 28 itself may be directly pushed away from the
latch 22.
[0042] The lever 14 may simply be hinged to the holder 12 or may be
spring-loaded, for example. The lever 14 may be operated such that
rotation of the lever 14 forces the piercing element 24 into the
barrel of a syringe that is positioned in the holder 12, thereby
puncturing the barrel of the syringe and creating an opening for
venting. The lever 14 may be designed with a cam or a screw, such
that turning the cam or screw would force the lever 14 toward the
syringe and cause the piercing element 24 to enter the syringe.
[0043] According to another embodiment of the present invention,
the piercing element 24 may be located directly on the holder 12
and may be used to pierce the barrel of a syringe positioned in the
holder 12 simply by pushing on the piercing element 24 itself. The
piercing element 24 may also be designed with a cam or a screw,
such that turning the cam or screw would force the piercing element
24 toward the syringe and cause the piercing element 24 to enter
the syringe.
[0044] The piercing element 24 may be positioned in a variety of
places on the lever 14 or the holder 12. According to an embodiment
of the present invention, the piercing element 24 enters the
syringe below the plunger cap but substantially close to the
plunger cap so that use of the barrel of the plunger is maximized
if the syringe is pierced by the piercing element 24.
[0045] The piercing element 24 may be designed such that there are
no loose pieces of the syringe resulting from the piercing element
24 being forced into the syringe. Rather, when the piercing element
24 enters the syringe, the syringe remains intact. According to an
embodiment of the present invention, the piercing element 24 may be
designed to "enter and scoop." According to another embodiment of
the present invention, the piercing element 24 may be designed to
"peel away" a portion of the syringe. In other words, the piercing
element 24 enters the syringe and scoops away a portion of the
syringe so that loose pieces of the syringe due not fall into or
contaminate the fluid in the barrel of the syringe.
[0046] A degassing tool 40 according to another embodiment of the
present invention may be seen in FIG. 2. The embodiment of the
invention shown in FIG. 2 is similar to the embodiment of the
invention shown in FIG. 1 except that the locking mechanism is
effected by a first loop 42, a second loop 43 and a third loop 44
that are hingedly, rotatably or otherwise moveably attached to the
base 26. The first loop 42, the second loop 43 or the third loop 44
may be rotated about the base 26 to engage the latch 22, thereby
maintaining the slide 16 in a fixed position. The different sizes
of the first loop 42, the second loop 43 and the third loop 44
allow the slide 16 to be fixed into multiple positions. Additional
locking loops may be implemented if desired to accommodate a
plurality of locked positions for the slide.
[0047] Referring back to FIG. 1, use of the degassing tool 10 may
include inserting a standard size syringe into the holder 12. A
plunger of the syringe may be positioned into the plunger aperture
20 of the slide 16. The handle aperture 32 of the slide 16 may be
grabbed by a user to pull the plunger of the syringe back away from
the barrel of the syringe that is prevented from moving by the
holder 12. When the slide 16 is pulled back far enough, the latch
22 will engage the locking mechanism 28, thereby maintaining the
position of the slide 16 and, consequently, the plunger of the
syringe. Thus, a vacuum will be formed and maintained in the barrel
of the syringe because the plunger is able to maintain its position
after drawing a vacuum. Any fluid residing in the barrel of the
syringe may then be degassed.
[0048] The degassing tool 10 may be made from a variety of
materials. For example, the degassing tool 10 may be made from
aluminum, stainless steel or from various types of plastics.
[0049] A generalized method of using a degassing tool to degas a
fluid and refill a negative pressure reservoir according to an
embodiment of the present invention is shown in FIG. 3. At step 50
a syringe is inserted into the tool. The syringe may be a standard
size, off-the-shelf syringe common in the industry. At step 52,
medication is drawn using a needle in the syringe such that the
medication fills the barrel of the syringe. The medication may be
insulin or some other fluid. Steps 50 and 52 may be interchanged if
desired by the user.
[0050] At step 54, a stopcock may be used to close the syringe. At
step 56, the plunger of the syringe may be retracted so that a
vacuum is pulled in the barrel of the syringe. Thus, after step 56,
the barrel of the syringe will include a fluid portion and a
vacuous portion. Because the degassing tool may include a locking
mechanism, the plunger may be locked into a fixed position, thereby
maintaining the vacuum in the barrel of a syringe.
[0051] With a vacuum maintained in the barrel of the syringe, the
medication or other fluid in the barrel may be degassed at step 58.
Degassing of the medication or other fluid may be accomplished in a
variety of ways. For example, according to an embodiment of the
present invention, the entire syringe/degassing tool combination
may be manually shaken by the user so that air or other gasses that
have been dissolved in the medication or other fluid may be
released into the vacuum. Shaking the syringe/degassing tool
increases the amount of surface area of the fluid seen by the
vacuum, thereby allowing a greater amount of gas to be expelled
from the fluid into the vacuum.
[0052] Once the medication has been sufficiently degassed, the
stopcock may be opened so that gasses residing in the previously
evacuated area of the barrel of the syringe may be released through
a needle in the syringe. If desired, steps 54 through 60 may be
repeated to maximize the amount of degassing of the medication or
other fluid. For example, according to an embodiment of the present
invention, three cycles of steps 54 through 60 may be sufficient to
adequately degas a fluid before injecting the fluid into a patient
or a pump or reservoir implanted in a patient.
[0053] Subsequent to the last implementation of step 60, a needle
in the syringe may be inserted into a negative pressure device
implanted in the patient. The negative pressure device may be, for
example, a pump, such as an insulin pump, for example, or other
negative pressure reservoir. Because the implanted device is a
negative pressure device, the fluid residing in the barrel of the
syringe will normally enter the patient due to the prevailing,
sufficiently greater pressure of the external environment. However,
a query may be made at step 64. If the fluid entered the patient,
the procedure is complete at step 68. If the fluid did not enter
the patient, the syringe may be pierced by the piercing element so
that air enters the barrel of the syringe and increases the
pressure on the fluid in the barrel of the syringe. This should
cause the fluid to enter the negative pressure device implanted
into the patient.
[0054] If fluid exists in the implanted device prior to degassing
and filling/refilling the device, it may be desirable to remove the
old fluid before filling the device with new fluid. A generalized
method of using a degassing tool to remove fluid from a negative
pressure device according to an embodiment of the present invention
is shown in FIG. 4. At step 70, a syringe is inserted into a
degassing tool such as, for example, the degassing tool shown in
FIG. 1. At step 72, a stopcock may be inserted onto the syringe and
closed to seal the syringe. At step 74, the plunger of the syringe
may be retracted to pull a vacuum in the barrel of the syringe.
[0055] At step 76, a needle may be inserted onto the stopcock. At
step 78, the needle is then inserted into the patient so that it
makes contact with a fill/refill port on the implanted device. At
this point, the pressure in the negative pressure device should be
greater than that in the barrel of the syringe, which is at vacuum.
Next, at step 80, the stopcock is opened and the fluid in the
implanted device should flow freely into the barrel of the
syringe.
[0056] A degassing tool 90 according to another embodiment of the
present invention is shown in FIG. 5. The degassing tool 90 in FIG.
5 is shown with a syringe 102 having a plunger 104 inserted. The
embodiment of the invention shown in FIG. 5 includes, but is not
limited to a holder 92 for holding the syringe 102. Affixed to the
holder 92 is an extension piece 94. The extension piece 94 may be
hingedly or otherwise moveably attached to the holder 92.
[0057] Attached to the extension piece 94 is a locking post 96
which is hingedly or otherwise movably attached to the extension
piece 94. The degassing tool 90 shown in FIG. 5 may also include a
lever 98 and a piercing mechanism 100, similar to the lever and
piercing mechanism shown in the embodiment of the invention of FIG.
1.
[0058] When using the embodiment of the invention shown in FIG. 5,
the syringe 102 may be positioned into the holder 92. The plunger
104 may then be drawn back away from the holder 92 so that a vacuum
is pulled within the barrel of the syringe 102. The extension piece
94 and the locking post 96, being hingedly or otherwise moveably
attached to each other, and the extension piece 94 being hingedly
or otherwise moveably attached to the holder 92, may be rotated
away from the syringe and the plunger in order to draw the plunger
104 back. Once the plunger 104 has been drawn to the desired
position, the extension piece 94 and the locking post 96 may be
rotated toward the plunger 104 so that the locking post 96 prevents
the plunger 104 from moving back into the barrel of the syringe
102. Thus, the vacuum pulled within the barrel of the syringe is
maintained.
[0059] FIGS. 6a and 6b show perspective views of the holder 92 and
the extension piece 94, respectively. The holder 92 may be sized
and shaped to accept standard syringe sizes that are common in the
industry. The extension piece 94, according to the embodiment of
the invention shown at FIG. 6b, is formed as a "double L" shape to
facilitate a moveable connection to the holder 92 and the locking
post 96.
[0060] While particular embodiments of the present invention have
been shown and described, it will be obvious to those skilled in
the art that the invention is not limited to the particular
embodiments shown and described and that changes and modifications
may be made without departing from the spirit and scope of the
appended claims.
* * * * *