U.S. patent number RE38,074 [Application Number 10/116,486] was granted by the patent office on 2003-04-08 for contrast medium delivery system and associated method.
This patent grant is currently assigned to AngioDynamics, Inc.. Invention is credited to Eamonn Hobbs, Daniel K. Recinella.
United States Patent |
RE38,074 |
Recinella , et al. |
April 8, 2003 |
Contrast medium delivery system and associated method
Abstract
A device cooperating with a pump for guiding a contrast medium
from a source thereof to a catheter for delivery to a patient's
vascular system. The device comprises a dual check valve, a tubular
member, an in-line check valve and a three-port stopcock. The dual
check valve has an inlet port connectable to the source of contrast
medium, an inlet-outlet port connectable to the pump, and an outlet
port coupled to the tubular member. The in-line check valve is
connected to the tubular member at a point spaced from the dual
check valve for preventing fluid flow towards the dual check valve.
The stopcock connected at a first port to the in-line check valve,
a second port of the stopcock being operatively connectable to the
catheter. Using this device, medical personnel infuses contrast
medium into the patient from the source without having to
disconnect any element from the device during the infusion
process.
Inventors: |
Recinella; Daniel K.
(Queensbury, NY), Hobbs; Eamonn (Queensbury, NY) |
Assignee: |
AngioDynamics, Inc.
(Queensbury, NY)
|
Family
ID: |
26706857 |
Appl.
No.: |
10/116,486 |
Filed: |
April 3, 2002 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
Reissue of: |
966671 |
Nov 10, 1997 |
06315762 |
Nov 13, 2001 |
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Current U.S.
Class: |
604/247; 604/183;
604/505; 604/535 |
Current CPC
Class: |
A61M
5/007 (20130101) |
Current International
Class: |
A61M
5/00 (20060101); A61M 005/00 () |
Field of
Search: |
;604/523,533,535,183,185,186,246,247,500,505,508 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Nguyen; Anhtuan T.
Assistant Examiner: Thompson; Michael M
Attorney, Agent or Firm: Reed Smith
Parent Case Text
CROSS-REFERENCE TO A RELATED APPLICATION
This application relies for priority purposes on U.S. provisional
application No. 60/031,116 filed Nov. 14, 1996.
Claims
What is claimed is:
1. A system for delivering contrast medium at low pressure to a
catheter for delivery to a patient's vascular system comprising: a
dual check valve adapted to be connected to a lower pressure source
of contrast medium, said dual check valve having an inlet port, an
outlet port and an inlet-outlet port, said dual check valve
containing a first one-way valve at said inlet port automatically
responsive to the relatively low pressure at said inlet-outlet port
to permit down-stream fluid flow and to prevent upstream fluid
flow, said dual check valve containing a second one-way valve at
said outlet port automatically responsive to the relatively high
pressure at said inlet-outlet port to permit downstream fluid flow
and to prevent upstream fluid flow, said inlet-outlet port in
communication with said first and second one-way valves and adapted
to be connected to a pump, a connecting tubular member having an
upstream and a downstream end, said upstream end in communication
with said outlet port of said dual check valve, suction at said
inlet-outlet port by .[.a.]. .Iadd.the .Iaddend.pump causing flow
of medium from whatever source is coupled to said inlet port
through said first one-way valve into the pump, said second one-way
valve preventing fluid flow upstream from said connecting tubular
member into the pump, positive pressure at said inlet-outlet port
from .[.a.]. .Iadd.the .Iaddend.pump causing fluid flow through
said second one-way valve and said outlet port into said tubular
member, said first one-way valve preventing upstream fluid flow to
.[.a.]. .Iadd.the .Iaddend.source, and a third one-way valve in
communication with said down-stream end of said tubular member to
permit down-stream fluid flow from said tubular member and to
prevent upstream fluid flow into said tubular member.
2. The system of claim 1 further comprising: a first stopcock
upstream of said inlet port of said dual check valve to turn flow
from .[.a.]. .Iadd.the .Iaddend.source on and off.
3. The system of claim 1 further comprising: a second stopcock
downstream of said third one-way valve to turn flow into .[.a.].
.Iadd.the .Iaddend.catheter on and off.
4. The system of claim 2 further comprising: a second stopcock
downstream of said third one-way valve to turn flow into .[.a.].
.Iadd.the .Iaddend.catheter on and off.
5. The system of claim 1 further comprising: a second dual check
valve downstream of said down-stream end of said tubular member and
incorporating said third one-way valve, said second dual check
valve having a second inlet-outlet port adapted to be connected to
an ancillary pump, said second dual check valve having a fourth
one-way valve in communication with said second inlet-outlet port
to permit downstream fluid flow from .[.an.]. .Iadd.the
.Iaddend.ancillary pump, said third one-way valve preventing
upstream fluid flow from .[.an.]. .Iadd.the .Iaddend.ancillary
pump.
6. The system of claim 5 further comprising: a first stopcock
upstream of said inlet port of said dual check valve to turn flow
from .[.a.]. .Iadd.the .Iaddend.source on and off.
7. The system of claim 5 further comprising: a .[.second.].
stopcock downstream of said second dual check valve to turn flow
into .[.a.]. .Iadd.the .Iaddend.catheter on and off.
8. The system of claim 6 further comprising: a second stopcock
downstream of said second dual check valve to turn flow into
.[.a.]. .Iadd.the .Iaddend.catheter on and off. .Iadd.
9. An apparatus for delivering contrast medium at low pressure to a
catheter for delivery to a patient's vascular system comprising: a
dual check valve adapted to be connected to a lower pressure source
of contrast medium, said dual check valve having a first inlet
port, a first outlet port and a first inlet-outlet port, said dual
check valve containing a first one-way valve at said first inlet
port automatically responsive to the relatively low pressure at
said first inlet-outlet port to permit downstream fluid flow and to
prevent upstream fluid flow, said dual check valve containing a
second one-way valve at said first outlet port automatically
responsive to the relatively high pressure at said first
inlet-outlet port to permit downstream fluid flow and to prevent
upstream fluid flow, said first inlet-outlet port in communication
with said first and second one-way valves and adapted to be
connected to a pump, a connecting tubular member having an upstream
and a downstream end, said upstream end in communication with said
first outlet port of said dual check valve, suction at said first
inlet-outlet port by the pump causing flow of medium from whatever
source is coupled to said first inlet port through said first
one-way valve into the pump, said second one-way valve preventing
fluid flow upstream from said connecting tubular member into the
pump, and positive pressure at said first inlet-outlet port from
the pump causing fluid flow through said second one-way valve and
said first outlet port into said tubular member, said first one-way
valve preventing upstream fluid flow to the
source..Iaddend..Iadd.
10. The apparatus of claim 11 further comprising: a first stopcock
upstream of said first inlet port of said dual check valve to turn
flow from the source on and off..Iaddend..Iadd.
11. The apparatus of claim 10 further comprising: a second stopcock
on said downstream end of said tubular member to turn flow into the
catheter on and off..Iaddend..Iadd.
12. The apparatus of claim 9 further comprising: a stopcock on said
downstream end of said tubular member to turn flow into the
catheter on and off..Iaddend..Iadd.
13. The apparatus of claim 9 further comprising: an in-line check
valve connected to said downstream end of said tubular member,
wherein said in-line check valve has a second inlet port in which
said tubular member is connected, a second inlet-outlet port
adapted to be connected to an ancillary pump, and a second outlet
port connected to a first stopcock which is connected to the
catheter..Iaddend..Iadd.
14. The apparatus of claim 13 further comprising: a second stopcock
upstream of said first inlet port of said dual check valve to turn
flow from the source on and off..Iaddend..Iadd.
15. The apparatus of claim 14 further comprising: a third stopcock
disposed between the ancillary pump and the second inlet-outlet
port downstream said in-line check valve to turn flow into the
catheter on and off..Iaddend.
Description
BACKGROUND OF THE INVENTION
This invention relates to a device and a system for delivering
contrast medium to a patient. The device and system are especially
effective for delivering carbon dioxide gas to the vascular system
of a patient. This invention also relates to an associated method
for delivering contrast medium such as carbon dioxide gas to a
patient.
Delivery systems for contrast media have been used for many years
in the medical field. Keeping the system a "closed system" so that
no room air will be introduced is critical to the features of these
delivery systems. With the advent of carbon dioxide gas or CO.sub.2
as a viable fluid for displacing blood in vessels for visualization
under Digital Subtraction Angiography (DSA), the need to keep air
out of the system is of even greater importance. Air and CO.sub.2
are invisible so introduction of air into a CO.sub.2 delivery
system would pose a danger to a patient if it were inadvertently
injected into the vasculature.
CO.sub.2 has been shown to be an excellent fluid to be used for
displacing blood in vessels. This void that is created in the
vessel can be visualized with DSA. But since CO.sub.2 is invisible
introduction of room air into the system would pose a great danger
to the patient. The air would go undetected and, once in the
patient's vasculature, could cause a blockage or even an air
embolism to the brain resulting in a stroke or death.
Because of this serious safety issue, it would make sense to use a
closed system for the safe delivery of CO.sub.2. However, the
conventional method used for delivering CO.sub.2 is connecting a
syringe to a CO.sub.2 cylinder, filling the syringe with CO.sub.2,
disconnecting the syringe from the cylinder and re-connecting to a
catheter or tube set. If more CO.sub.2 is needed, the syringe is
disconnected from the catheter and refilled of the cylinder. This
method allows for introduction of air into the system at every
disconnection.
One method that was developed to reduce the number of
disconnections was to attach the CO.sub.2 cylinder directly to a
stopcock with a syringe attached at on port and the catheter to the
patient attached to the other port. When the syringe was to be
filled, the stopcock would be opened to the syringe and the
cylinder pressure would force CO.sub.2 into the syringe. For
injection into the patient, the stopcock would be closed to the
cylinder and the syringe plunger would be advanced forward pushing
the CO.sub.2 gas into the catheter and, subsequently, into the
patient.
The problem with this method is that the CO.sub.2 cylinder pressure
is much higher than blood pressure (830 psi vs. 6 psi). If the
stopcock is turned the wrong way, the cylinder is open to the
catheter and liters of CO.sub.2 will be delivered into the patient
in less than a minute. Accordingly, the cylinder must be isolated
from the patient and the delivery system used must be closed
without providing a chance for the introduction of air.
BRIEF DESCRIPTION
It is an object of the invention to provide an improved device or
system for delivering contrast medium to a patient's vascular
system.
Another object of the present invention is to provide such a device
or system wherein air can be effectively eliminated prior to the
feeding of the contrast medium to the patient.
It is a further object of the present invention to provide such a
device or system wherein highly pressurized sources of contrast
medium are isolated from the patient to prevent chance introduction
of excessive amounts of contrast medium into the patient.
An additional object of the present invention is to provide such a
device or system wherein explosive introduction of gaseous contrast
medium (carbon dioxide) into the patient can be minimized or
eliminated.
Yet another object of the present invention is to provide such a
device or system which is inexpensive and made of essentially
off-the-shelf components.
A related object of the present invention is to provide an
associated method for infusing contrast medium into a patient's
vascular system.
These and other objects of the present invention are attained in a
device cooperating with a pump for guiding a contrast medium from a
source thereof to a catheter for delivery to a patient's vascular
system. The device comprises a dual check valve, a tubular member,
an in-line check valve and a three-port stopcock. The dual check
valve has an inlet port connectable to the source of contrast
medium, an inlet-outlet port connectable to the pump, and an outlet
port coupled to the tubular member. The in-line check valve is
connected to the tubular member at a point spaced from the dual
check valve for preventing fluid flow towards the dual check valve.
The stopcock connected at a first port to the in-line check valve,
a second port of the stopcock being operatively connectable to the
catheter.
Using this device, medical personnel may infuse contrast medium
into the patient from the source without having to disconnect any
element from the device during the infusion process. The entire
system, including the source, the device, the pump and the
catheter, is purged of air prior to beginning the infusion and air
cannot be reintroduced back into the system during the infusion.
The dual check valve permits continued connection of the pump to
the system. Thus, where the pump takes the form of a syringe, the
pump need not be disconnected from the system between an intake
stroke and an ejection stroke of the syringe plunger. The in-line
check valve prevents flow of blood from the catheter into the
tubular member. It is contemplated that the dual check valve, the
syringe and the tubular member are first purged of air by directing
contrast medium through those parts of the system and out a third
port of the stopcock, and subsequently the catheter, which is
connected to the second port of the stopcock, is purged of air by
allowing the patient's blood to flow through the catheter and out
the third port of the stopcock.
According to another feature of the present invention, the in-line
check valve is a dual check valve having an additional inlet port
connected to the tubular member, an additional outlet port
connected to the stopcock, and an additional inlet-outlet port
operatively connectable to an ancillary pump such as a syringe. An
additional stopcock may be disposed between the ancillary pump and
the additional inlet-outlet port.
This additional structure facilitates a clearing of the catheter of
blood prior to infusion of the contrast medium into the patient.
The ancillary syringe has a limited volume not significantly
greater than the volume in a path extending through the in-line
check valve, the stopcock and the catheter. The ancillary syringe
is operated to draw contrast medium from the source through the
first dual check valve and then to drive the contrast medium
through the catheter but not substantially into the patient. The
system is now ready for the controlled infusion of contrast
medium.
Preferably, the dual check valve, the tubular member, the in-line
check valve and the stopcock are all permanently bonded to one
another. This prevents the air leakage into the system.
In accordance with another feature of the present invention, the
source of contrast medium is a flexible bag. A method for supplying
a contrast medium to a patient's vascular system thus comprises
operatively connecting the flexible bag to the patient's vascular
system via a gas transfer system, purging the gas transfer system
of air, and thereafter delivering contrast medium from the flexible
bag through the gas transfer system to the patient's vascular
system.
The flexible bag contains contrast medium at ambient atmospheric
pressure, thus preventing accidental infusion of contrast medium
and particularly excessive amounts of contrast medium into the
patient. Prior to connecting the flexible bag to the
contrast-medium transfer device, the bag is filled multiple times
with contrast medium and squeezed empty to clear the bag of
air.
In a device or system in accordance with the present invention for
delivering contrast medium to a patient's vascular system, air can
be effectively eliminated prior to the feeding of the contrast
medium to the patient. Highly pressurized sources of contrast
medium are isolated from the patient, thereby preventing
inadvertent introduction of excessive amounts of contrast medium
into the patient. Also, explosive introduction of gaseous contrast
medium (carbon dioxide) into the patient can be minimized or
eliminated.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a schematic elevational view of a system for controllably
infusing carbon dioxide contrast medium into a patient's vascular
system, in accordance with the present invention.
FIG. 2 is a schematic elevational view of a modified system in
accordance with the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
As illustrated in FIG. 1, a system for controllably infusing carbon
dioxide contrast medium into a patient's vasculature comprises a
flexible reservoir bag 11, a one-way reservoir bag stopcock 12, a
delivery syringe 13, a dual check valve 14, an in-line check valve
15, a distal one-way stopcock 16, a purge syringe 17, a connecting
tube 22, and a patient stopcock 23. This system will remove the
high-pressure CO.sub.2 cylinder from the vicinity of the patient
and maintain a closed system that reduce or eliminate the chance
introduction of air into the patient's vasculature.
Reservoir bag 11 is made of a soft elastomeric, non-porous
material. When bag 11 is filled to its capacity or just under
capacity (500-2000 ml), the bag is at ambient atmospheric pressure.
Therefore, bag 11 will not have a tendency to deliver CO.sub.2 gas
into the patient even if the bag is coupled directly to the
patient's vasculature. The patient's blood pressure will be higher
than the pressure of the bag. The use of flexible reservoir bag 11
acts as a safety feature for two reasons. First, there is no
pressurized source of CO.sub.2 gas placed in communication with the
patient. Second, bag 11 provides a large reservoir of CO.sub.2 so
that numerous connections and disconnections are obviated.
Dual check valve 14 is permanently bonded to tube 22. Tube 22 is
permanently bonded to in-line check valve 15. In-line check valve
15 is permanently bonded to patient stopcock 23 and distal stopcock
16. Every component in the system except syringes 13 and 17,
including dual check valve 14, tube 22, in-line check valve 15, and
stopcocks 16 and 23, can withstand pressures from ambient to 1200
psi. Therefore, this system could be used with high pressure
injectors, as well as with bag 11.
The system of FIG. 1 is used as follows.
Reservoir bag 11 is coupled to a CO.sub.2 cylinder (not
illustrated) via a connecting tube 35 and reservoir bag stopcock
12. The cylinder contains 99.7% pure medical grade carbon dioxide
and is equipped with a two-stage gas regulator (not shown), a
filter (not shown) to remove sub-micron particles, and a Luer-Lok
fitting (not shown) to which reservoir bag 11 is coupled. Bag 11 is
filled with CO.sub.2 gas, disconnected from the cylinder and
squeezed until the bag is empty. Bag 11 is then connected to the
CO.sub.2 cylinder again and re-filled. This process is repeated two
to three times to ensure that all the air has been removed from
reservoir bag 11. On the last filling, bag 11 is filled and
reservoir stopcock 12 is closed. Bag 11 is then detached from the
CO.sub.2 cylinder and connected to a side or inlet port 24 of dual
check valve 14 via a Luer-Lok fitting 36. Inlet port 24 contains a
one-way valve 19 which permits fluid to enter the dual check valve
14 through that port but prevents fluid from flowing out of check
valve 14. Delivery syringe 13, a Luer-Lok syringe or mechanical
injector syringe, is attached to a side or inlet-outlet port 25 of
dual check valve 14 and purge syringe 17 is attached to distal
stopcock 16.
With all components attached, reservoir stopcock 12 is opened. The
plunger 26 of delivery syringe 13 is drawn back, aspirating
CO.sub.2 gas into the syringe. When plunger 26 is drawn, a one-way
valve element 18 in an outlet port 27 of dual check valve 14 closes
and does not allow any flow from downstream into the check valve
14. One-way check valve 19 opens and permits fluid flow from
reservoir bag 11 into delivery syringe 13.
When plunger 26 of delivery syringe 13 is advanced forward in a
pressure stroke, one-way valve element 19 closes and one-way valve
element 18 opens, thereby permitting CO.sub.2 gas to flow down the
tube 22 and out an open port 28 of patient stopcock 13 at the end
of the system. By executing this procedure two or three times, the
user purges delivery syringe 13, dual check valve 14, tube 22 and
in-line check valve 15 of all room air so that only CO.sub.2 gas is
present in those components of the system.
Purge syringe 17 and distal stopcock 16 are purged next. Upon the
opening of distal stopcock 16, purge syringe 17 can draw CO.sub.2
gas through check valve 15 and tube 22. A plunger 29 of purge
syringe 17 is drawn back. With that action, one-way check valves 18
and 19 of dual check valve 14 and a one-way valve element 20 of
in-line check valve 15 are open and allow gas from reservoir bag 11
to flow into purge syringe 17. Another one-way valve element 21 of
in-line check valve 15 closes to keep air out of the system. When
plunger 29 of purge syringe 17 is depressed in a pressure stroke,
the CO.sub.2 gas moves forward. One-way valve element 20 closes and
one-way valve element 21 opens, thereby permitting CO.sub.2 gas to
flow out through port 28 at the end of the system. The performance
of this action two or three times serves to remove any air
contained in in-line check valve 15 and patient stopcock 23.
The above-described priming procedure takes only a few minutes.
Once all the air has been removed from the system, a port 28 of
patient stopcock 23 is attached to a catheter 32. Blood can be
drawn through side port 30 of patient stopcock 23, assuring that
all air has been removed from the catheter. When patient stopcock
23 is closed to side port 30, the system is totally closed and room
air cannot enter. One-way valve element 21 of dual in-line check
valve 15 keeps blood from flowing upstream along tube 22 towards
dual check valve 14.
When a CO.sub.2 infusion procedure is being performed, it is
important to reduce the resistance to gas flow in catheter 32 as
much as possible. If the resistance is too high, the gas can build
up pressure and exit the catheter explosively. This can result in
pain for the patient and inconsistent imaging.
The best way to reduce the resistance is to remove the liquid
(saline or blood) that is in catheter 32. This liquid will pose the
most significant resistance problems to CO.sub.2 flow. To perform a
liquid removal procedure, distal stopcock 16 is opened and a
limited aliquot (e.g., 3-5 ml) of CO.sub.2 is drawn into purge
syringe 17. Plunger 29 of purge syringe 17 is subsequently advanced
in a pressure stroke. During this pressure stroke, one-way valve
element 20 of in-line check valve 15 closes and one-way valve
element 21 opens. CO.sub.2 gas flows through patient stopcock 23
into catheter 32. This small amount of CO.sub.2 displaces the blood
or other liquid that is in catheter 32, thereby generating a gas
path which is lower in resistance to flow than the patient's blood.
One-way valve element 21 of in-line check valve 15 closes from the
back pressure of the CO.sub.2 gas in catheter 32, thus making it
difficult for blood to flow back into catheter 32.
To infuse carbon dioxide into a patient, plunger 26 of delivery
syringe 13 is drawn back. One-way check valve element 18 closes and
one-way check valve element 19 opens, allowing flow from reservoir
bag 11 into delivery syringe 13. Distal stopcock 16 is closed.
Plunger 26 of the delivery syringe 13 is advanced in a pressure
stroke and the gas is injected into the patient through one-way
check valve element 18, tube 22, in-line check valve 15, patient
stopcock 23 and catheter 32. For another injection, the retraction
and advancing of plunger 26 are repeated. The user can continue
until all the CO.sub.2 in reservoir bag 11 is used, without having
to disconnect any of the elements, e.g., syringe 13, from the
system.
FIG. 2 shows a modified design in which in-line check valve 15 has
been replaced with an in-line check valve in the form of a single
one-way valve 34 and in which stopcock 16 and purge syringe 17 have
been removed. The advantage to this design is that there is one
less connection so the system becomes even more safe to use. The
purge of the liquid from the catheter is done using delivery
syringe 13.
While the invention has been described in connection with what is
presently considered to be the most practical and preferred
embodiments, it is to be understood that the invention is not to be
limited to the disclosed embodiment, but on the contrary, is
intended to cover various modifications and equivalent arrangements
included within the spirit and scope of the appended claims.
* * * * *