U.S. patent application number 09/984803 was filed with the patent office on 2002-03-07 for priming system.
This patent application is currently assigned to PALL CORPORATION. Invention is credited to Bormann, Thomas J., Delgiacco, Gerard R., Matkovich, Vlado I..
Application Number | 20020029021 09/984803 |
Document ID | / |
Family ID | 26688837 |
Filed Date | 2002-03-07 |
United States Patent
Application |
20020029021 |
Kind Code |
A1 |
Bormann, Thomas J. ; et
al. |
March 7, 2002 |
Priming system
Abstract
A device (100) such as a drip chamber that can be filled to a
predetermined level is disclosed. The device comprises a housing
(14) and a porous medium (10), wherein the porous medium allows gas
to pass therethrough.
Inventors: |
Bormann, Thomas J.;
(Melville, NY) ; Matkovich, Vlado I.; (Glen Cove,
NY) ; Delgiacco, Gerard R.; (Yonkers, NY) |
Correspondence
Address: |
LEYDIG VOIT & MAYER, LTD
700 THIRTEENTH ST. NW
SUITE 300
WASHINGTON
DC
20005-3960
US
|
Assignee: |
PALL CORPORATION
2200 Northern Boulevard
East Hills
NY
11548
|
Family ID: |
26688837 |
Appl. No.: |
09/984803 |
Filed: |
October 31, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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09984803 |
Oct 31, 2001 |
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09171994 |
Oct 29, 1998 |
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09171994 |
Oct 29, 1998 |
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PCT/US97/07706 |
Apr 18, 1997 |
|
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60016611 |
May 1, 1996 |
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60030490 |
Nov 15, 1996 |
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Current U.S.
Class: |
604/252 |
Current CPC
Class: |
A61M 5/1411 20130101;
A61M 1/3627 20130101; A61M 2205/7536 20130101 |
Class at
Publication: |
604/252 |
International
Class: |
A61M 005/00; A61M
005/14 |
Claims
What is claimed:
1. A device for transferring fluid comprising: a housing suitable
for holding gas and a liquid, the housing providing a gas flow
path; and a vent comprising a porous medium that allows gas but not
liquid in the housing to pass through the medium and from the
housing until the medium is contacted by the liquid and gas flow
stops, the porous medium including a liquophilic element and a
liquophobic element, the device allowing a desired amount of liquid
to held in the housing wherein the amount is less than the total
liquid capacity of the housing.
2. A drip chamber comprising: a housing including a porous medium
that allows liquid to fill the housing to a predetermined level
without completely filling the housing with liquid; the porous
medium allowing gas to pass from the housing exteriorly to the
device until the porous medium is contacted by the liquid, the
porous medium including a liquophilic element and a liquophobic
element.
3. A method for transferring fluid comprising: passing a fluid into
a device comprising a housing including a fluid reservoir for gas
and liquid; and a vent communicating with the housing, said vent
comprising a liquophilic element and a liquophobic element; passing
liquid into the housing and passing gas through the porous medium
until the liquid contacts the porous medium and the housing holds a
desired amount of liquid that is less than the total liquid
capacity of the housing.
4. The method of claim 3, comprising passing a biological fluid
through the device.
5. The method of claim 3, comprising passing a non-biological fluid
through the device.
6. The method of claim 5, comprising passing first and second
fluids through the device, wherein the first fluid comprises the
non-biological fluid, and the second fluid comprises a biological
fluid.
7. The device of claim 1, wherein the housing includes a plurality
of concentric channels along the gas flow path, said vent and said
housing being cooperatively arranged to allow gas to pass along the
plurality of concentric channels and from the housing.
8. The device of claim 1, wherein the housing includes a plurality
of radial channels along the gas flow path, said vent and said
housing being cooperatively arranged to allow gas to pass along the
plurality of radial channels, and from the housing.
9. The device of claim 1, wherein the housing includes a plurality
of concentric channels and a plurality of radial channels along the
gas flow path, said vent and said housing being cooperatively
arranged to allow gas to pass along the plurality of concentric
channels and the plurality of radial channels, and from the
housing.
10. The device of claim 1, wherein the porous medium has a
bacterial blocking pore structure.
11. The device of claim 7, wherein the porous medium has a
bacterial blocking pore structure.
12. The device of claim 1, wherein the housing comprises a port
through which gas passes from the housing exteriorly to the device,
the device further comprising a removable cap engageable with the
housing for covering the port.
13. The device of claim 7, wherein the housing comprises a port
through which gas passes from the housing exteriorly to the device,
the device further comprising a removable cap engageable with the
housing for covering the port.
14. The drip chamber of claim 2, wherein the porous medium has a
bacterial blocking pore structure.
15. The drip chamber of claim 2, wherein the housing comprises a
port through which gas passes from the housing exteriorly to the
device, the drip chamber further comprising a removable cap
engageable with the housing for covering the port.
16. The method of claim 3, wherein the device is not inverted while
passing the fluid into the device.
17. The method of claim 3, wherein the device housing is not
compressed before passing the fluid into the device.
Description
[0001] This application is a continuation of U.S. patent
application Ser. No. 09/171,994, filed Oct. 29, 1998, which is a
371 National phase of PCT/US97/07706, filed Apr. 18, 1997. This
application claims the benefit of U.S. provisional patent
application No. 60/016,611, filed May 1, 1996, and No. 60/030,490,
filed Nov. 15, 1996, which are incorporated by reference in their
entireties.
TECHNICAL FIELD
[0002] This invention relates to a device and method for
transferring fluid, especially for venting and/or priming fluid
transfer and/or processing systems. The present invention is
particularly useful in the administration of parenteral fluids,
e.g., drugs, nutrients, hydration solutions, and/or transfusion
products such as blood components.
BACKGROUND OF THE INVENTION
[0003] Many fluid transfer systems such as fluid processing systems
function more efficiently if they can be at least partially purged
of air or gas before use. For example, it may be desirable to prime
a fluid transfer system, e.g., to displace or remove air from one
or more devices and/or tubes in the system to allow them to be
filled with liquid before continuously operating the system. Since
pockets of air or gas can block or slow the flow of liquid,
minimizing or eliminating the presence of air or gas can allow the
liquid to flow more quickly through the system.
[0004] Additionally, some transfer systems, e.g., for administering
fluid to a patient, should minimize or prevent air or gas from
passing beyond a certain location in the system. For example, some
intravenous (IV) systems include a drip chamber or a bubble trap to
capture air or gas so that it will not be administered to the
patient. The drip chamber can also be used to allow the operator of
the system to monitor the rate at which the fluid is administered.
For example, the operator may observe the drip chamber to ensure
that the patient is receiving the liquid at a given rate, e.g., a
rate of so many drops of liquid per minute. If desired, the rate
can be changed and the new rate can be monitored by observing the
rate at which the drops of liquid pass through the chamber.
[0005] There are drawbacks to conventional fluid transfer systems.
For example, some systems for administering transfusion products
require a labor intensive effort by the operator of the system.
Illustratively, when transfusing blood or blood products,
especially when filtering and administering blood at the patient's
bedside, the operator of the system may have to start the flow of
blood from the source bag with the drip chamber initially inverted
until the drip chamber is about 2/3 full. Then the partially filled
drip chamber is placed in the upright position and the system is
primed. After the system is primed, blood can be administered, and
the rate monitored through the drip chamber.
[0006] The operator must carefully monitor the initial filling of
the inverted drip chamber, since overfilling the chamber leads to
difficulties in monitoring the drip rate. For example, a high level
of fluid in the chamber can provide insufficient space for a drop
to form before it contacts the fluid in the chamber, making it
difficult to count drops. On the other hand, underfilling the
chamber increases the possibility that air will pass through the
chamber, with possibly adverse consequences for the patient.
[0007] Accordingly, there is a need in the art for a device and
method that provides for efficient priming of a fluid processing
system, e.g., that allows a drip chamber to be filled to a desired
level without a labor intensive effort. In particular, there is a
need in the art for a "level setting" drip chamber, that
automatically vents air or gas, without overfilling.
[0008] The present invention provides for ameliorating at least
some of the disadvantages of the prior art. These and other
advantages of the present invention will be apparent from the
description as set forth below.
SUMMARY OF THE INVENTION
[0009] In accordance with an embodiment of the present invention, a
device for use in a fluid transfer system is provided that vents
gas, without overfilling with liquid. Illustratively, gas can be
vented from a flow metering device such as a drip chamber, and the
drip chamber can be filled to a desired level of liquid, wherein
the amount of liquid in the chamber is less than the total liquid
capacity of the chamber. In a more preferred embodiment, the device
vents gas, and seals after venting, without overfilling with
liquid.
[0010] In an embodiment, once fluid flow toward the device is
initiated by the operator of the fluid transfer system, the device
automatically vents gas and fills to a desired level, without
operator involvement. For example, the operator does not need to
squeeze and/or invert the device. Moreover, the device can be
filled with liquid, and subsequently utilized during administration
of the liquid, while keeping the device in an essentially upright
position, and without allowing gas or air to enter the device
through the vent.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a cross-sectional view an embodiment of a venting
device according to the present invention.
[0012] FIG. 2 is a view of the device of FIG. 1 along line A-A.
[0013] FIG. 3 is a view of the device of FIG. 2 along line B-B,
showing a porous medium for passing gas therethrough located in the
device.
[0014] FIG. 4 is a cross-sectional view of the upper chamber and
the porous medium of the device of FIG. 1.
[0015] FIG. 5 is a cross-sectional view of the lower chamber of the
device of FIG. 1.
[0016] FIG. 6 is an embodiment of a fluid processing system
according to the present invention, including a venting device, and
a device for filtering biological fluid.
[0017] FIG. 7 is an embodiment of another fluid processing system
according to the present invention, including a venting device.
[0018] FIG. 8 is a cross-sectional view of another embodiment of a
venting device according to the present invention.
[0019] FIG. 9 is an embodiment of another fluid processing system
according to the present invention, including a cross-sectional
view another embodiment of a venting device.
[0020] FIG. 10 is an embodiment of another fluid processing system
according to the present invention, including a venting device, a
device for filtering biological fluid, and a plurality of
containers.
SPECIFIC DESCRIPTION OF THE INVENTION
[0021] In accordance with the present invention, a device for
transferring fluid is provided comprising a housing comprising a
fluid reservoir for gas and liquid; a vent communicating with the
housing, the vent comprising a liquid sealable porous medium that
allows gas in the housing to pass through the medium until the
medium is contacted by the liquid, the vent and the housing being
cooperatively arranged to allow the gas to be vented from the
housing and for liquid to fill the housing to a predetermined level
that is less than the total liquid capacity of the housing.
[0022] The present invention also provides a device for
transferring fluid comprising a housing having a fluid reservoir
for gas and liquid; a vent communicating with the housing, the vent
comprising a porous medium that allows gas in the housing to pass
through the medium until the medium is contacted by the liquid, the
vent and the housing being cooperatively arranged to allow the gas
to be vented from the housing and for liquid to fill the housing to
a predetermined level that is less than the total liquid capacity
of the housing.
[0023] In some embodiments, the device for transferring fluid
comprises a flow metering device such as a drip chamber. The device
may also include a structure such as a cap, plug, and/or valve
capable of engaging with the housing, e.g., to cover and/or seal
the vent.
[0024] The present invention also provides a drip chamber
comprising a housing including a porous medium that allows liquid
to fill the housing to a predetermined level without completely
filling the housing with liquid, the medium allowing gas to pass
from the housing until the medium is contacted by the liquid, the
medium including a liquophilic element and a liquophobic
element.
[0025] In accordance with the invention, a system for transferring
at least one fluid is provided, the system comprising the device
for transferring fluid, and a container suitable for holding a
fluid to be transferred, wherein the device is in fluid
communication with the container. In an embodiment, the device
comprises a drip chamber, and the system also includes a filter,
e.g., a blood filter such as a leukocyte filter, interposed between
the drip chamber and the container. In some embodiments, the system
includes a plurality of containers, e.g., suitable for holding
different fluids to be transferred.
[0026] An embodiment of a system for transferring at least one
fluid in accordance with the invention comprises the device for
transferring fluid, and a filter suitable for filtering a fluid to
be transferred, wherein the device is in fluid communication with
the container.
[0027] The present invention also provides a method for
transferring one or more fluids comprising passing a fluid into a
device comprising a housing including a fluid reservoir for gas and
liquid, and a vent communicating with the housing, the vent
comprising a liquid sealable porous medium that allows gas in the
housing to pass through the medium until the medium is contacted by
a liquid; passing liquid into the housing and passing gas through
the porous medium until the liquid contacts the porous medium and
the housing is filled to a predetermined level that is less than
the total liquid capacity of the housing.
[0028] In accordance with embodiments of the invention, the
transferred fluid or fluids are transferred to a desired location,
e.g., the fluids are transferred to a container, or are
administered to a patient. In an embodiment, one of the fluids to
be transferred is a biological fluid such as blood or a blood
component, and the method also includes administering the
biological fluid to a patient. For example, a first fluid, e.g., a
non-biological fluid such as saline, can be passed through the
device and administered, and subsequently a second fluid such as a
biological fluid can be passed through the device and administered.
In some embodiments, the method includes filtering one or more
fluids, e.g., to remove undesirable material therefrom, before
administering the fluid(s). Illustratively, at least one fluid such
as a biological fluid, e.g., blood, a blood product, or a blood
component, can be filtered to remove undesirable material such as
leukocytes therefrom, before administering the biological fluid to
the patient.
[0029] Embodiments of the present invention provide for efficient
separation of gas or air from a fluid flow path. More preferred
embodiments provide for efficient separation of gas or air from
fluid delivery systems, e.g., systems involving parenterally
administered fluids, such as intravenously administered liquids,
for example, biological fluids such as blood, blood products, and
blood components; drugs and/or nutrients. Thus, gas can be
separated from the fluid delivery system, e.g., vented to the
atmosphere, or the gas can be directed to a desired location within
the system, e.g., away from a desired liquid flow path. As used
herein, the term "gas" includes air.
[0030] In accordance with the invention, a biological fluid
includes any treated or untreated fluid associated with living
organisms, particularly blood, including whole blood, warm or cold
blood, and stored or fresh blood; treated blood, such as blood
diluted with at least one physiological solution, including but not
limited to saline, nutrient, and/or anticoagulant solutions; blood
components, such as platelet concentrate (PC), platelet-rich plasma
(PRP), platelet-poor plasma (PPP), platelet-free plasma, plasma,
fresh frozen plasma (FFP), components obtained from plasma, packed
red cells (PRC), transition zone material or buffy coat (BC); blood
products derived from blood or a blood component or derived from
bone marrow; red cells separated from plasma and resuspended in a
physiological fluid; and platelets separated from plasma and
resuspended in a physiological fluid. The biological fluid may have
been treated to remove some of the leukocytes before being
processed according to the invention. As used herein, blood product
or biological fluid refers to the components described above, and
to similar blood products or biological fluids obtained by other
means and with similar properties.
[0031] A "unit" is the quantity of biological fluid from a donor or
derived from one unit of whole blood. It may also refer to the
quantity drawn during a single donation. Typically, the volume of a
unit varies, the amount differing from patient to patient and from
donation to donation. Multiple units of some blood components,
particularly platelets and buffy coat, may be pooled or combined,
typically by combining four or more units.
[0032] Each of the components of the invention will now be
described in more detail below. Like components have like reference
numbers.
[0033] In the exemplary embodiment illustrated in FIGS. 1-5, and 9,
device 100 includes a housing 14, having at least one inlet 1 and
an outlet 2; a lumen 21 for fluid flow between the inlet and the
outlet; and a vent 3 providing a gas flow path. Vent 3 comprises a
porous medium 10 that allows gas, but not liquid, to pass from the
lumen 21 through a port 4 into a gas passageway 5 and through a
port 30. Typically, porous medium 10 is located in the housing 14,
and has a surface 10a facing the inlet 1, and a surface 10b facing
the outlet 2. Preferably, porous medium 10 has a portion of the
surface 10a near or adjacent to port 4 of gas passageway 5. In some
embodiments, e.g., as illustrated in FIG. 9, the device 100
includes at least two inlets 1, 1'.
[0034] Typically, as illustrated in FIGS. 1, 3, and 4, housing 14
includes a first portion 16, having an inlet 1, and a groove 29.
The first portion 16 also includes a nipple 22 having a port 23
leading to lumen 21. Preferably, the nipple 22 and port 23 allow
liquid to enter the lumen 21 in the form of droplets.
[0035] As illustrated in FIGS. 1 and 5, housing 14 also includes a
second portion 18 having an outlet 2, and a lip 19. In the
embodiment shown in FIG. 1, the first portion 16 and the second
portion 18 are sealed to form a first chamber 15 and a second
chamber 20 encompassing lumen 21 and porous medium 10.
[0036] Preferably, as illustrated in FIGS. 2 and 3, porous medium
10 is annular in shape, and surface 10a faces a series of ribs 25,
26, 28, and/or channels 24, 27 in the first portion 16. Typically,
in those embodiments having an annular porous medium 10, the ribs
25, 26, and 28, and the channels 24 are generally concentric. In
the illustrated embodiment, first portion 16 also includes radial
channels 27.
[0037] In an embodiment, the device 100 includes a flow control
device 401, e.g., a valve as illustrated in FIG. 9. Exemplary flow
control devices 401 comprise check valves or one-way valves.
[0038] In another embodiment as illustrated in FIG. 8, the porous
medium 10 is located more exteriorly to housing 14. For example,
porous medium 10 can be disposed in a separate vent housing 50
adjacent housing 14. Gas and liquid pass from lumen 21 through port
7 and passageway 6 to porous medium 10 in vent housing 50. Porous
medium 10 allows gas, but not liquid, to pass therethrough to port
30.
[0039] FIGS. 6, 7, 9 and 10 illustrate embodiments of a typical
system 500 utilizing device 100 during the transfer of at least one
fluid to a desired destination. For example, the embodiments of the
systems are especially useful for the administration of at least
one fluid such as a parenteral fluid to a patient. FIGS. 6, 9, and
10 also include an optional filter 300, e.g., for filtering a fluid
before administering it to the patient. The illustrated embodiments
of the system include a container 200 for holding a fluid such as a
parenteral fluid, wherein the container is in fluid communication,
via conduits such as conduits 210, 210', 220 and 230, with the
filter 300 (if present), the device 100, and the destination of the
fluid, e.g., a patient. In some embodiments, e.g., as illustrated
in FIGS. 9 and 10, the system includes two or more containers 200,
200' for holding fluid.
[0040] Typically, in those embodiments of a system that include a
plurality of containers, the containers hold different parenteral
fluids. Illustratively, using the embodiments of the systems
illustrated in FIGS. 9 and 10 for reference, container 200' may be
suitable for holding one fluid, e.g., a biological fluid such as
blood, one or more blood products, or one or more blood components,
and container 200 may be suitable for holding another fluid, e.g.,
a non-biological fluid that is compatible with the biological
fluid, such as saline.
[0041] The system also includes at least one, and more preferably
at least two, flow control devices 400,400' such as clamps.
Typically, the system, which can be open or closed, includes one or
more connectors. For example, in some embodiments, the system
includes a "spike" for connecting a conduit to a container. Of
course, in other embodiments, components of the system can be
connected in accordance with other protocols known in the art,
e.g., via sterile docking.
[0042] It is intended that the present invention is not to be
limited to the above listed components of the system. For example,
the system may have components such as, but not limited to,
connectors, additional containers, injection ports, and additional
vents such as gas inlets and/or gas outlets. For example, FIG. 10
illustrates an embodiment of a system including an additional vent
101 comprising a gas inlet and/or gas outlet, wherein the vent 101
includes a porous medium suitable for passing gas therethrough.
[0043] As noted above, the embodiments of the device and system
provide for venting gas, and vent 3 provides a gas flow path,
wherein gas, but not liquid, passes through a porous medium 10.
Porous medium 10, which is preferably a membrane or film, includes
at least a liquophobic portion, and preferably includes a
liquophobic portion and a liquophilic portion. Even more
preferably, the porous medium 10 includes at least one liquophobic
porous element or layer and at least one liquophilic porous element
or layer. Typically, a liquophobic element is superimposed on a
liquophilic element. Preferably, the liquophobic element or layer
is hydrophobic, and the liquophilic element or layer is
hydrophilic. In some of the embodiments wherein the porous medium
10 lacks a liquophilic element or layer, the liquophobic element or
layer is hydrophobic.
[0044] Both the liquophobic and the liquophilic elements or layers
allow gas to pass through. However, the liquophobic element is not
wettable, or poorly wettable, by the liquid being transferred in
the system, and the liquophilic element is wettable by the liquid.
Once the liquophilic element is contacted or covered (e.g., wetted)
by the liquid being transferred, gas flow through the vent 3 stops,
and the medium 10 is sealed. Once the medium is sealed, gas or air
external to the device 100 is also prevented from flowing through
the medium, even when the level of liquid in the device
subsequently decreases. Of course, particularly when the device 100
is left essentially unattended while fluid is being administered,
it may be additionally desirable to block or seal the port 30,
e.g., with a cap or cover, after gas has been vented and the
liquophilic element has been wetted. In those embodiments wherein
the porous medium 10 lacks a liquophilic element or layer, after
the liquophobic element has been covered by the liquid, the port 30
should be blocked or sealed, at least temporarily, to prevent gas
external to the device 100 from entering the device through the
port.
[0045] In the embodiment shown in FIG. 1, porous medium 10 includes
a first surface 10a and a second surface 10b. In some embodiments,
porous medium 10 includes two layers, e.g., superimposed layers,
with surface 10a representing the surface of liquophobic layer that
is not facing the liquophilic layer, and with surface 10b
representing the surface of liquophilic layer that is not facing
the liquophobic layer. As illustrated in FIGS. 2-4, a portion of
surface 10a is near or adjacent port 4 at the end of gas passageway
5. In another embodiment including superimposed layers, as
illustrated in FIG. 8, a portion of surface 10b is near or adjacent
port 7 at the end of passageway 6.
[0046] In accordance with one embodiment according to FIGS. 1-3,
the porous medium 10 comprises the liquophobic element and the
liquophilic element arranged in the housing 14 to vent gas through
gas passageway 5 until the liquophilic element is contacted or
covered by the liquid being transferred.
[0047] Similarly, in accordance with one embodiment according to
FIG. 8, the medium 10 comprises the liquophobic element and the
liquophilic element arranged near the housing 14 to vent gas from
passageway 6 until the liquophilic element is contacted with, or
covered by, the liquid being transferred.
[0048] In some of the preferred embodiments, gas flow automatically
stops when the liquophilic element is wetted, without liquid
substantially passing through the liquophobic element. Once the gas
flow stops, the device 100 has been filled to the desired level,
without overfilling. Gas remaining in the interior of the housing
14 will not be displaceable, and the liquid will stop rising in the
housing. Furthermore, once the liquophilic element is wetted, the
medium 10 is sealed, preventing gas from entering the device 100
through the medium.
[0049] In those embodiments wherein the porous medium 10 includes a
liquophobic element and lacks a liquophilic element, gas flow
automatically stops when the liquophobic element is covered with
liquid, without the liquid substantially passing through the
liquophobic element. Once the gas flow stops, the device 100 has
been filled to the desired level, without overfilling. Gas
remaining in the interior of the housing 14 will not be
displaceable, and the liquid will stop rising in the housing.
[0050] A variety of materials may be used, provided the requisite
properties of the porous medium 10 are achieved. These properties
include the necessary strength to handle the differential pressures
encountered in use and the ability to provide the desired
permeability without the application of excessive pressure.
Suitable starting materials include synthetic polymers including
polyamides, polyesters, polyolefins, particularly polypropylene and
polymethylpentene, perfluorinated polyolefins, such as
polytetrafluoroethylene, polysulfones, polyvinylidene difluoride,
polyacrylonitrile and the like, and compatible mixtures of
polymers. Within the class of polyamides, suitable polymers
include, for example, polyhexamethylene adipamide,
poly-.epsilon.-caprolactam, polymethylene sebacamide,
poly-7-aminoheptanoamide, polytetramethylene adipamide (nylon 46),
polyhexamethylene azeleamide, and polyhexamethylene adipamide
(nylon 66). In an embodiment, skinless, substantially
alcohol-insoluble, hydrophilic polyamide membranes, such as those
described in U.S. Pat. No. 4,340,479, are suitable.
[0051] Typically, the porous medium 10 has a pore size of about 5
micrometers or less, more preferably, about 3 micrometers or less,
even more preferably, about 2 micrometers or less. In those
embodiments including administering fluid(s) to a patient, the
medium 10 typically has a bacterial blocking pore structure to
preclude bacteria from entering the system through the vent. For
example, the medium can have a pore size of about 0.2 micrometer or
less. In those embodiments having liquophobic and liquophilic
layers, either or both layers can have the bacterial blocking pore
structure.
[0052] The device can include additional layers or elements, e.g.,
for use as spacers and/or supports with respect to the porous
medium 10. An exemplary support or spacer layer can be a mesh or
screen.
[0053] Exemplary porous media 10, including liquophobic and
liquophilic elements, include those disclosed in International
Publication No. WO 91/17809 and U.S. Pat. Nos. 5,126,054 and
5,451,321.
[0054] The housing 14 can be fabricated from any suitable
impervious material, preferably a rigid material, such as any
thermoplastic material, which is compatible with the fluid being
processed. For example, the housing can be fabricated from a metal,
or from a polymer. In an embodiment, the housing is a polymer,
preferably a transparent or translucent polymer, such as an
acrylic, polypropylene, polystyrene, or a polycarbonated resin.
Such a housing is easily and economically fabricated, and allows
observation of the passage of the liquid through the housing.
[0055] The surfaces of the housing contacting the fluid may be
treated or untreated. For example, the surfaces of the housing
contacting the fluid may be rendered liquophilic for better
priming. Methods for treating the surface of the housing include
but are not limited to radiation grafting and gas plasma
treatment.
[0056] The housing may be configured for ease of use. For example,
the housing may include a bracket or hook for ease of mounting or
support during administration of a parenteral fluid.
[0057] The housing can be sealed as is known in the art. For
example, first portion 16 and second portion 18 can be welded
together, e.g., after fitting lip 19 into groove 29. Additionally,
the porous medium 10 can be sealed within the housing 14 to achieve
convenience of use, rapid priming, and efficient gas clearance.
Suitable methods for sealing, fitting, and/or bonding the medium
within or to the housing are known in the art. For example, the
porous medium 10 can be compression sealed or interference fit
within the housing, or bonded to the housing. The porous medium can
be welded to the housing, e.g., heat welded or ultrasonically
welded.
[0058] The housing 14 can include an arrangement of ribs, walls or
projections, or may comprise one or more channels, grooves,
conduits, passages, or the like which may be serpentine, parallel,
curved, radial, spiral, or have a variety of other configurations.
Typically, at least one projection faces the first surface 10a
and/or faces the second surface 10b of the porous medium 10. The
ribs, walls or projections may be used to define the channels,
grooves, conduits, or passages. Typically, the housing 14 includes
at least one rib, wall, or projection to support and/or position
the porous medium 10 within the housing. In some embodiments, the
housing includes at least one rib, wall or projection to improve
the efficiency of gas flow, e.g., by supporting or positioning the
porous medium 10 within the housing while providing clearance
between portions of the first surface 10a and the housing.
[0059] Typically, as illustrated in FIG. 2 first portion 16
includes ribs 25 and channels 24, which are preferably concentric
ribs and channels, to allow more efficient flow of gas to the gas
passageway 5. The first portion can also have radial channels 27,
and at least one, more preferably, at least two, additional ribs
such as concentric ribs 26 and 28. FIGS. 2 and 3 also illustrate
rib 26, that preferably positions the medium 10 with respect to
first portion 16.
[0060] In the embodiment illustrated in FIG. 1, the first portion
16 and the second portion 18 are sealed to form a first chamber 15
and a second chamber 20, encompassing lumen 21. The first and
second chambers can be similar in volume, or one chamber can be
larger in volume than the other. For example, in some embodiments
according to FIG. 1, the ratio of the volume of the first chamber
to the second chamber can be in the range of about 1:1 to about
3:1.
[0061] In some embodiments, e.g., as illustrated in FIG. 8, the
porous medium 10 can be located in an additional housing, such as
vent housing 50. Exemplary housings include those disclosed in
International Publication No. WO 91/17809 and U.S. Pat. Nos.
5,126,054 and 5,451,321. These International Publications and
Patents also disclose suitable vents 101 (e.g., as illustrated in
FIG. 10) such as gas inlets and/or gas outlets.
[0062] In some embodiments, the device 100 can also include a cap
or closure, e.g., for covering or sealing port 30. For example, in
accordance with any embodiments of the device 100 (e.g., with or
without a check valve, with or without a liquophilic element), a
cap can be used to cover port 30 to prevent the entry of gas, and
to uncover port 30 to allow gas to exit the device.
[0063] The device 100 may be incorporated into a variety of fluid
transfer and/or processing systems or sets. Embodiments of
exemplary systems 500, which are preferably parenteral fluid
administration sets, are illustrated in FIGS. 6, 7, 9 and 10.
[0064] Typically, the system includes at least one container for
holding the fluid to be transferred, and one or more conduits that
provide fluid communication between the container, the device 100,
and the destination of the fluid, e.g., a patient receiving the
transferred fluid. As illustrated in FIGS. 7, 9, and 10, the system
can also include at least one filter for filtering the fluid to be
transferred.
[0065] The containers 200, 200' which can be used in the system can
be constructed of any material compatible with the fluid to be
transferred. A wide variety of suitable containers are already
known in the art. Typically, container 200, 200' comprises a
flexible material, for example, polyvinyl chloride (PVC). An
exemplary container is a flexible bag, e.g., as is used for holding
blood or blood components. Alternatively, the containers may be
composed of a non-flexible material. It is intended that the
invention should not be limited by the type or composition of the
container being employed.
[0066] As with the containers, the conduits 210, 210', 220, and 230
can be constructed of any material that is compatible with the
fluid(s) to be transferred. Typically, the conduits comprise
flexible material. A preferred material is PVC, for example. As
used herein, the conduits are any tubing or means which provide
fluid communication between the various components of the
administration set. At least one flow control device 400,400' such
as a clamp (including, for example, a roller clamp), seal,
stopcock, valve, transfer leg closure, or the like, may be
associated with at least one of the conduits in order to facilitate
a desired function, i.e., to open, close, and/or modulate the
desired flow of the fluid (e.g., parenteral fluid) and/or gas. In
some embodiments, particularly for some of the embodiments that
include administering fluid to a patient, the flow control device
400' downstream of the device 100 comprises a roller clamp to
control the flow rate.
[0067] Typically, as illustrated in FIGS. 7, 9, and 10, the system
also includes at least one filter 300, preferably upstream of
device 100, to filter the fluid to be transferred. A variety of
filters are suitable for use in the system, e.g., IV filters, e.g.,
for administering drugs and/or nutrients; and blood filters,
including leukocyte filters. Typically, the filter comprises a
filter assembly, including a housing having an inlet and an outlet
and providing a fluid flow path between the inlet and the outlet,
and a porous filter medium for filtering the fluid disposed between
the inlet and the outlet and across the fluid flow path.
[0068] In some embodiments, the leukocyte filter comprises a
synthetic polymeric leukocyte depletion medium, more preferably a
synthetic, polymeric, fibrous medium. In an embodiment, the
leukocyte depletion medium has a Critical Wetting Surface Tension
(CWST) of about 55 dynes/cm or greater, e.g., about 60 dynes/cm or
greater. For example, the CWST can be in the range of about 62
dynes/cm to about 100 dynes/cm. Exemplary leukocyte filters include
those disclosed in, for example, U.S. Pat. Nos. 4,925,572;
4,880,548; and 5,217,627.
[0069] Embodiments of a method according to the invention include
locating the device in a fluid flow path between a source of fluid,
e.g., a container, and the intended destination of the fluid, e.g.,
a patient, and transferring the fluid through the device. For
example, referring to the exemplary embodiments illustrated in
FIGS. 6, 7, 9, and 10, fluid flow control devices 400,400' such as
clamps upstream and downstream of the device 100 are typically
closed initially, and then the flow control device upstream of
device 100 is opened, to allow fluid to enter the housing. Since
the flow control device downstream of the device 100 remains
closed, gas (e.g., gas displaced into the housing by liquid passing
through the conduit(s)) passes through the vent 3 as the device
fills with liquid.
[0070] The device 100 can be filled and used (e.g., during fluid
administration) without being inverted. Preferably, device 100
remains in an upright, or essentially upright, position during
filling and subsequent use. Accordingly, once the operator of the
fluid transfer system, e.g., a nurse, opens the appropriate
upstream flow control device(s), the device can automatically vent
and fill to a desired level, without operator involvement. As a
result, there is no need for the operator to carefully monitor the
system during priming, and the operator can perform other tasks in
the meantime. Since the device automatically fills to a
predetermined level, there is no need for the operator to rush back
to the system to avoid overfilling. After the device fills to the
desired level, the flow control device downstream of device 100 is
opened, and the fluid is passed to the desired destination.
[0071] Using FIG. 1 (illustrating an embodiment of the device), as
well as FIGS. 7, 9, and 10 (illustrating embodiments of the system)
for reference, fluid is passed, e.g., by gravity, from container
200 through at least one conduit to device 100, while the flow
control device 400' downstream of device 100 is closed. Liquid and
gas enter the housing 14 via inlet 1. Preferably, device 100 (FIG.
1) includes a nipple 22 and a port 23, and fluid passes into lumen
21 in the form of droplets. Since the fluid flow path downstream of
the device 100 remains closed, the device acts as a reservoir, as
second chamber 20 fills with liquid. As the second chamber 20 fills
with liquid, gas is displaced. Some of this gas is vented from the
device, i.e., the gas passes from the interior of the housing along
a gas flow path through porous medium 10 via surface 10b and
surface 10a, and through port 4 and gas passageway 5 to the
exterior of the housing. In those embodiments wherein the housing
includes ribs and channels, e.g., ribs 25 and channels 24 and 27 as
illustrated in FIG. 2, gas passes along channels 24 and 27 through
port 4 to gas passageway 5 to more efficiently vent the device.
[0072] Second chamber 20 (shown in FIG. 1) continues to fill with
liquid, and eventually, the level of liquid will reach surface 10b
of porous medium 10. Once liquid covers the surface 10b, gas flow
through the vent 3 stops, without liquid substantially passing
through the medium 10. Once the gas flow stops, the device 100 is
filled to the desired level, as gas remaining in the interior of
the housing 14 will not be displaceable, and the liquid will stop
rising in the housing. Furthermore, in those embodiments wherein
porous medium 10 includes a liquophobic element (presenting surface
10a) and a liquophilic element (presenting surface 10b), once
liquid covers the liquophilic element, the vent 3 is sealed. Once
vent 3 is sealed, gas exterior to the device is prevented from
entering the device, even if the liquid level in second chamber 20
decreases. As noted earlier, if desired, the port 30 can be blocked
or covered (e.g., with a cap) after the vent 3 is sealed.
[0073] In some of those embodiments wherein the porous medium 10
lacks a liquophilic element or layer, the port 30 should be blocked
or covered (at least temporarily) after gas flow stops and the
liquid covers surface 10b. However, after transfer, e.g.,
administration, of the fluid is essentially completed, the operator
of the system can uncover the port to recover some of the fluid
retained in the device 100. For example, after administering the
fluid to a patient, the operator can remove the cap, and drain some
of the liquid retained in the device and downstream conduit(s) into
the patient, and then the operator can manually stop the flow of
liquid before gas can reach the patient.
[0074] In preferred embodiments, gas flow stops when the device 100
is about 2/3 filled with liquid. Illustratively, when passing a red
blood cell-containing fluid such as packed red cells (PRC) or whole
blood into the device, the device has a total capacity of, for
example, about 15 cc, and gas flow stops when the device contains
about 10 cc of liquid. In another embodiment, when passing a
platelet-containing fluid such as platelet concentrate (PC) into
the device 100, the device has a total capacity of, for example,
about 9 cc, and gas flow stops when the device contains about 6 cc
of liquid.
[0075] Once the device is filled, the liquid can be delivered as
desired. For example, using FIGS. 7, 9, and 10 for reference, the
flow control device 400' downstream of device 100 (e.g., a flow
control device such as a roller clamp) can be opened, and the fluid
can be administered to a patient.
[0076] In some embodiments, e.g., as illustrated in FIGS. 6, 9, and
10, the system 500 also includes a filter 300 such as a leukocyte
depletion filter, and the container 200 (FIG. 6) or 200' (FIGS. 9
and 10) contains a leukocyte-containing biological fluid such as
blood or a blood component. Using FIG. 6 for reference (the
embodiments of the system illustrated in FIGS. 9 and 10 can be
operated similarly), flow control devices 400,400' are typically
initially closed, and the flow control device 400 between the
container of leukocyte-containing biological fluid and filter 300
is opened. If desired, the container of biological fluid may be
squeezed to more efficiently prime the filter 300. Fluid exiting
the filter 300 enters the device 100, which vents gas and fills
with liquid as described earlier. After the device automatically
vents and fills to a desired level, the flow control device 400'
downstream of device 100 can be opened, and the liquid can be
administered to the patient.
[0077] If desired, the device 100 can initially be filled with one
fluid, e.g., a non-biological fluid such as saline, and after the
device vents gas and fills with this liquid, the liquid is
administered and then a second fluid, e.g., a biological fluid that
is compatible with the non-biological fluid, is passed through the
device and administered.
[0078] For example, using the embodiment of the system illustrated
in FIG. 10 for reference, wherein the exemplary fluids are saline
and biological fluid, container 200 contains saline, and the
container 200' contains a leukocyte-containing biological fluid,
flow control devices 400,400' are typically initially closed, and
then flow control device 400 between the container 200 and the
device 100 is opened. Saline enters the device 100 which
automatically vents and fills to the desired level.
[0079] The flow control device 400 between container 200' and the
filter 300 can also be opened, and the filter can be primed as is
known in the art. For example, an additional vent 101 such as a gas
outlet can be interposed between filter 300 and the junction of
conduits 210 and 220, and, with a flow control device 400
(interposed between the gas outlet and the junction of conduits 210
and 220) closed, gas displaced by the biological fluid can be
passed through the gas outlet. If the gas outlet includes a
liquophilic element and a liquophobic element, gas will pass
through the elements until the liquophilic element is covered or
wetted with liquid, and gas flow stops. If the gas outlet includes
a liquophobic element, the outlet should be capped or blocked after
the gas displaced by the biological fluid is passed through the
outlet. Alternatively, e.g., in some embodiments wherein the system
lacks an additional vent 101 such as a gas outlet, gas displaced by
the biological fluid can be passed via conduits 220 and 210 into
container 200 after a flow control device 400 interposed, for
example, between filter 300 and the junction between conduits 210
and 220, is opened.
[0080] If desired, the filter 300 can be primed with one fluid
(e.g., biological fluid) and the device 100 can be filled with
another fluid (e.g., saline) simultaneously, or nearly
simultaneously. For example, using the embodiment of the system
illustrated in FIG. 10 for reference, if flow control devices 400
(interposed between the gas outlet and the junction of conduits 210
and 220), and 400' (downstream of the device 100), both remain
closed, opening the other flow control devices 400 illustrated in
FIG. 10 allows gas to be displaced through vent 101 (downstream of
filter 300) and port 30 (of device 100).
[0081] In accordance with these embodiments described above, the
flow control device 400' downstream of the device 100 is then
opened, and the first fluid (e.g., saline) is administered to the
patient. Subsequently, the flow control device 400 between
container 200 and the device 100 is closed, and the flow control
device 400 interposed between the filter 300 and the device 100 is
opened. The filtered biological fluid is then administered to the
patient.
[0082] If desired, the shift from administering one fluid to
administering another fluid can be carried out quickly and easily.
For example, the filter 300 can be primed with biological fluid,
and the device 100 can be filled to the desired level with saline
nearly simultaneously as described above. After the device 100
fills to the desired level, flow control device 400' is opened and
saline is administered. As soon as it is desirable to administer
the filtered biological fluid, the flow control device 400
interposed between container 200 and device 100 is closed, and the
flow control device 400 interposed between vent 101 and device 100
is opened. The filtered biological fluid will then pass into device
100 and the fluid is administered to the patient. Administration
can be carried out without delaying to prime the filter 300, since
the filter 300 was previously primed.
[0083] In some embodiments, e.g., wherein the filter 300 comprises
a leukocyte depletion filter, the biological fluid is depleted of
at least about 99%, more preferably, at least about 99.9%, or more,
of the leukocytes as the fluid passes through the leukocyte
depletion filter.
[0084] As noted above, embodiments of the method can also include
capping and uncapping the device 100. For example, the device can
include a cap that engages with the housing, e.g., to cover port
30, and the port can be uncapped while the device initially fills
with liquid and vents gas. After the device automatically fills to
the desired level, the port can be capped at least temporarily as
described earlier. If desired, the port can remain capped while the
fluid(s) are subsequently administered to the patient, e.g., to
provide an extra barrier preventing gas from the outside
environment from entering the device 100 through the port 30.
[0085] In a variation of the embodiments illustrated in FIGS. 1 and
9, porous medium 10 comprises a liquophobic element having surface
10a and surface 10b, and porous medium 10 lacks a liquophilic
element. Since surfaces 10a and 10b are both liquophobic, both
surfaces can resist the passage of liquid(s) therethrough.
Typically, as described above, the port 30 should be closed,
covered or blocked after liquid covers surface 10b of porous medium
10. Additionally, or alternatively, a liquid can be placed in gas
passageway 5 to provide a column of liquid in the passageway. Since
this liquid in the passageway 5 is typically discarded along with
the device after the device is used, it is more economical to
utilize a drug and nutrient free liquid such as water in the
passageway, in contrast with the parenteral fluid to be passed
through the device and into the patient.
[0086] In accordance with another embodiment, the device 100 can
include a flow control device such as a valve that allows gas to
pass from the device and prevents gas from entering the device. For
example, the flow control device can be disposed in the gas
passageway 5, or a cap can include the flow control device 401.
Illustratively, in an embodiment of the invention wherein device
100 has a liquophobic porous medium 10, and includes a check valve
in the gas passageway 5, gas passes through the porous medium 10,
through the check valve in the gas passageway 5, and through the
port 30. The check valve allows gas to exit the device through port
30, and prevents gas from entering the device through the port
30.
[0087] Using FIGS. 1 and 7 for reference, as parenteral fluid
passes from container 200 into the device 100, liquid and gas enter
the housing via inlet 1. As the device fills with liquid, gas is
displaced, and passes through surfaces 10b and 10a, through the
column of liquid in passageway 5, and through port 30. Once the
level of fluid in second chamber 20 reaches surface 10b, gas flow
through medium 10 stops, without liquid passing through the medium
10. Moreover, the liquid in passageway 5 prevents gas or air
exterior to the device from entering the device, even if the liquid
level in second chamber 20 decreases. However, after the fluid
level reaches surface 10b, additional gas entering the housing via
inlet 1 can be vented through surfaces 10a and 10b, through the
column of liquid in passageway 5, and through port 30.
[0088] Alternatively, using FIGS. 1 and 9 for reference, as
parenteral fluid passes from container 200 into the device 100,
liquid and gas enter the housing via inlet 1. As the device fills
with liquid, gas is displaced, and passes through surfaces 10b and
10a, through the flow control device 401 (e.g., a check valve) in
passageway 5, and through port 30. Once the level of fluid in
second chamber 20 reaches surface 10b, gas flow through medium 10
stops, without liquid passing through the medium 10. Moreover, the
flow control device 401 in passageway 5 prevents gas or air
exterior to the device from entering the device, even if the liquid
level in second chamber 20 decreases. However, after the fluid
level reaches surface 10b, additional gas entering the housing via
inlet 1 can be vented through surfaces 10a and 10b, through the
flow control device in passageway 5, and through port 30. If
desired, the device can also include a cap that engages with the
housing, e.g., to cover port 30. In those embodiments, the device
is uncapped while gas is vented, and capped while parenteral fluid
is being administered.
[0089] Of course, in some alternative embodiments, e.g., wherein
the cap (rather than the gas passageway 5) includes the flow
control device 401 such as a check valve, the device can remain
capped while venting.
[0090] In some of those embodiments wherein a plurality of
parenteral fluids are utilized, e.g., in accordance with the
embodiments as illustrated in FIGS. 9 and 10, wherein the porous
medium 10 comprises a liquophobic medium, and lacks a liquophilic
element or portion, the first parenteral fluid (e.g., saline or a
blood component) may be passed into the device and gas is vented as
described above. After gas is vented, the parenteral fluid is
administered. Typically (using the embodiment illustrated in FIG. 9
for reference), when it is desirable to utilize a second (e.g., a
different) parenteral fluid, the flow control devices 400,400'
downstream of the device 100, and interposed between the device 100
and the container for the first parenteral fluid, are closed, and
the flow control device 400 interposed between the container for
the second parenteral fluid and the device 100 is opened. The
second parenteral fluid is passed into the device 100. Gas
displaced by the second parenteral fluid into the device can be
vented through the liquophobic porous medium 10 until the medium is
contacted with the second parenteral fluid. The downstream flow
control device 400' (e.g., associated with conduit 230) can then be
opened, and the second parenteral fluid can be administered. The
flow control device 401 and/or the capping of the port 30 will
prevent gas from entering the device through port 30.
[0091] All of the references cited herein, including publications,
patents, and patent applications, are hereby incorporated in their
entireties by reference.
[0092] While the invention has been described in some detail by way
of illustration and example, it should be understood that the
invention is susceptible to various modifications and alternative
forms, and is not restricted to the specific embodiments set forth.
It should be understood that these specific embodiments are not
intended to limit the invention but, on the contrary, the intention
is to cover all modifications, equivalents, and alternatives
falling within the spirit and scope of the invention.
* * * * *