Abstrict A drainage device is provided with a collection chamber, an underwater
seal chamber, and a separate flow chamber. The underwater seal chamber
which prevents the flow of atmospheric air from the device into
the pleural cavity of the patient is formed by a recessed portion
in a partition separating the underwater seal chamber from the collection
chamber. A passageway from the underwater seal chamber into the
collection chamber is located in the partition separating the chambers
and a baffle is formed around the opening to prevent excessive loss
of fluid from the underwater seal chamber into the collection chamber
when the device is inadvertently tilted. The flow chamber is closed
off from the collection chamber and is connected with the underwater
seal chamber by means of a tubular passageway adjacent the upper
wall of the drainage apparatus so as to prevent fluid from passing
from the underwater seal chamber into the outlet passageway. An
air flow meter is provided in the flow chamber to measure the rate
of air flow through the flow chamber.
Claims We claim:
1. A drainage device comprising a closed container, an inlet to
said container for connection with a thoracotomy tube, a partition
extending across at least a portion of the upper end of said container,
a recess formed in said partition beneath said inlet, a tubular
inlet member extending downwardly from said inlet to said recess
so that liquid in the recess forms a underwater seal with the lower
end of the inlet member, an outlet from said closed container, an
outlet chamber formed within said container enclosing said outlet,
a oneway valve disposed in an inlet opening in a wall of said outlet
chamber permitting fluid flow from said container inlet to said
outlet and preventing fluid flow in the opposite direction, and
a passageway connecting said inlet opening of said outlet chamber
with the remaining volume of said container, said passageway including
a series of contiguous vertically extending interconnecting conduits
interconnectd such that fluid flowing from the container inlet to
the outlet follows a tortuous path, including two bends of substantially
180 degrees within said series of vertically extending conduits.
2. A drainage device according to claim 1 and further including
a positive pressure relief valve disposed in said container connecting
said container with atmosphere to relieve positive pressure within
said container.
3. A drainage device according to claim 2 wherein said positive
pressure relief valve is disposed in a wall of said outlet chamber
on the outlet side of said oneway valve to form a passageway to
atmosphere in parallel with said outlet from said outlet chamber.
4. A drainage device according to claim 1 and further including
air flow meter means disposed in said passageway.
5. A drainage device according to claim 5 wherein said air flow
meter means includes a flow chamber located in said housing which
is fluidly connected to said outlet means and an air flow meter
located in said flow chamber, said air flow meter being fluidly
disposed between said passageway and said outlet means so that the
rate of gas flow is measured by said air flow meter.
6. A drainage device according to claim 5 and further including
an inhibiting means for inhibiting the accidental flow of liquid
into said air flow meter.
7. A drainage device according to claim 6 wherein said inhibiting
means includes a substantially vertical baffle extending around
the periphery of said opening in said partition.
8. A drainage device as claimed in claim 7 wherein said passageway
extends through said baffle and opens into the underwater seal chamber
above said opening in said partition.
9. A drainage device as claimed in claim 8 wherein said passageway
extends along the upper portion of said housing.
10. A drainage device as claimed in claim 6 wherein said inhibiting
means includes a trap means disposed fluidly between said passageway
and said flow chamber for collecting liquids passing through said
passageway.
11. A drainage device as claimed in claim 10 wherein said trap
chamber is visible from outside of said container so that the presence
of any liquid in said trap chamber is readily discernible.
12. A drainage device comprising:
a housing;
a collection chamber formed in said housing for receiving liquids
and gases from the body of a patient;
an inlet at the upper end of said housing;
a partition extending across a portion of the housing to form an
underwater seal chamber beneath said inlet;
a tubular extension connected to said inlet and projecting downwardly
into said underwater seal chamber whereby liquids from the body
of a patient are collected in the underwater seal chamber and provide
a liquid seal with the lower end of said tubular extension;
outlet means for providing an outlet to the atmosphere from said
housing;
an air flow meter means fluidly associated with said outlet means
for measuring the rate of flow of gases through said outlet means;
said air flow meter means including a flow chamber located in said
housing which is fluidly connected to said outlet means; a passageway
fluidly connecting the underwater seal chamber with said flow chamber
through which gases flow; and an air flow meter located in said
flow chamber, said air flow meter being fluidly disposed between
said passageway and said outlet means so that the rate of gas flow
is measured by said air flow meter and
said air flow meter including an enclosed elongate column disposed
in a generally vertical orientation having a horizontal cross-sectional
dimension which increases in size upwardly over the length of said
column; an air inlet located in said column adjacent the lower end
thereof; an outlet located in said column adjacent the upper end
thereof; and an air flotation element movably disposed in said column
so as to be lifted in said column by the flow of gases from said
passage to said outlet means, said air flotation element being sized
so as to fit relatively closely within said column such that, due
to the increase in cross-sectional dimension of said column, the
position of said air flotation element is indicative of the rate
of flow of gases through said flow chamber.
13. A drainage device comprising:
a housing;
a collection chamber formed in said housing for receiving liquids
and gases from the body of a patient;
an inlet at the upper end of said housing;
a partition extending across a portion of the housing to form an
underwater seal chamber beneath said inlet;
a tubular extension connected to said inlet and projecting downwardly
into said underwater seal chamber whereby liquids from the body
of patient are collected in the underwater seal chamber and provide
a liquid seal with the lower end of said tubular extension;
outlet means for providing an outlet to the atmosphere from said
housing;
an air flow meter means fluidly associated with said outlet means
for measuring the rate of flow of gases through said outlet means;
said air flow meter means including a flow chamber located in said
housing which is fluidly connected to said outlet means; a passageway
fluidly connecting the underwater seal chamber with said flow chamber
through which gases flow; and an air flow meter located in said
flow chamber, said air flow meter being fluidly disposed between
said passageway and said outlet means so that the rate of gas flow
is measured by said air flow meter;
said air flow meter including an enclosed elongate column disposed
in a generally vertical orientation having a a horizontal cross-section
dimension which increases in size upwardly over the length of said
column; an air inlet located in said column adjacent the lower end
thereof; an outlet located in said column adjacent the upper end
thereof; and an air flotation element movably disposed in said column
so as to be lifted in said column by the flow of gases from said
passage to said outlet means, said air flotation element being sized
so as to fit relatively closely within said column such that, due
to the increase in cross-sectional dimension of said column, the
position of said air flotation element is indicative of the rate
of flow of gases through said flow chamber; and
said outlet means further including a positive pressure relief
valve located between said one-way valve and the atmosphere.
Description BACKGROUND OF THE INVENTION
The invention relates to a drainage device and more particularly
to a drainage device which is designed to drain fluids from a body
cavity such as the pleural cavity and to measure the flow of air
through the drainage device.
It is essential for normal breathing that the space within the
pleural cavity surrounding the lungs be free of liquid and be subject
to a negative pressure so as to draw the lungs outwardly to fill
this pleural cavity in order to permit proper breathing. Any invasion
of the pleural cavity such as by lung surgery or foreign objects
which pierce the ribcage or, for example, where the patient has
pleurisy, generates fluids in the pleural cavity which tend to obstruct
normal breathing operations. It is necessary to provide a device
which can remove these fluids from the pleural cavity and, at the
same time, ensure that the desired degree of negative pressure is
maintained within the pleural cavity.
One of the basic types of apparatus which have been used for this
purpose is shown, for example, in U.S. Pat. Nos. 3363626 and 3363627.
This apparatus is known as an underwater drainage apparatus and
provides three chambers, one chamber comprising a collection chamber
for collecting the fluids drained from the pleural cavity through
a thoracotomy tube, a second chamber known as an underwater seal
chamber which protects the pleural cavity from being subject to
atmospheric pressure, and a third chamber known as a pressure manometer
chamber which serves to regulate the degree of negative pressure
within the pleural cavity. This type of apparatus has been highly
successful in both removing fluids from the pleural cavity and in
maintaining the desired degree of negativity within the pleural
cavity. However, such an apparatus required prefilling the underwater
seal chamber with water and also prefilling the pressure manometer
chamber to the desired level to maintain the desired degree of negativity
within the pleural cavity. Thus, there has been a need for a drainage
device which could be attached to the patient's pleural cavity and
which provided a simplified structure not requiring a vacuum pump.
For example, in emergency situations in the field where a vacuum
pump may not be available, it is necessary to provide a device which
can be attached to a patient's pleural cavity to permit drainage
of fluids to allow the lungs to expand.
The drainage system disclosed in U.S. Pat. No. 4015603 provided
an apparatus which may or may not be used with a vacuum source.
The underwater seal in this system is located at the lower end of
the thoracotomy tube at the upper end of the drainage device. In
the device shown in this prior patent, the underwater seal is formed
by liquid drained from the patient's pleural cavity. The location
of the underwater seal chamber at the lower end of the thoracotomy
tube as disclosed in U.S. Pat. No. 4015603 created a problem in
certain unusual circumstances. In a case of a patient having a blockage
in the bronchial tubes, such that the patient was having severe
problems in getting air into the lungs, exceedingly high negativity
was being created in the pleural cavity. Such high negativity caused
the fluid in the underwater seal to be drawn upwardly through the
thoracotomy tube and, if the degree of negativity was sufficiently
high, it was possible for fluid to reenter the pleural cavity. This
condition of fluid from the underwater seal chamber reentering the
pleural cavity could cause infection or otherwise create problems
for the patient. In addition, it was possible to entirely lose the
seal provided by the underwater seal chamber during periods of high
negativity in the pleural cavity. The loss of the water seal has
a potential for serious damage in the event the suction becomes
disconnected or the device is used as a two bottle system with the
collection chamber open to atmosphere.
In U.S. Pat. No. 3853128 there is disclosed a positive pressure
relief valve in a drainage apparatus having a conventional underwater
seal and manometer chamber. The positive pressure relief valve is
disposed between the underwater seal and manometer chambers and
provides relief from high pressure surges within the collection
chamber. The device disclosed in U.S. Pat. No. 3853128 must, however,
be prefilled prior to use and does not function as a two chambered
device which is usable without prefilling. In U.S. Pat. No. 3559647
there is disclosed an underwater drainage apparatus having seal
which is provided with a gas flow meter at the bottom of the seal.
The gas flow meter is comprised of a series of orifices located
at the bottom of the underwater seal. The more orifices which gas
passes through, the greater the gas flow. However, this type of
flow meter is suitable only for indicating the gas flow in steps.
SUMMARY OF THE INVENTION
In accordance with the invention an improved medical drainage device
for draining fluids from the body of a patient is provided which
enables the operator to monitor the air flow through the device.
The air flow meter is simple and rugged in construction and efficient
and dependable in use. According to the invention, the surgical
drainage apparatus comprises a housing with an outlet which is connected
to a suitable source of suction so that fluids can be drawn into
the housing through a fluid inlet. A collection chamber is formed
in the housing which receives the fluids from the patient and a
partition extending across a portion of the housing forms an underwater
seal chamber beneath the inlet. A tubular extension connected to
the inlet projects downwardly into the underwater seal chamber to
provide a fluid seal. An air flow meter means is fluidly associated
with the outlet means to measure the rate of flow of air through
the outlet means. The apparatus of the invention is completely "dry"
prior to use, i.e., does not require any prefilling by the user.
In a preferred embodiment of the invention, the air flow meter
means includes a flow chamber and a passageway extending from the
underwater seal chamber to the flow chamber. An air flow meter is
located in the flow chamber. Preferably, an inhibiting means inhibits
the accidental flow of liquids into the air flow meter. The inhibiting
means can be a vertical baffle around the opening of the partition
or a trap at the end of the passageway prior to the air flow meter.
The air flow meter is an enclosed elongate column having a horizontal
cross-sectional dimension which increases in size upwardly and an
air flotation element movably disposed in the column which is lifted
by the flow of air. A one-way valve is also provided to permit the
escape of gases from within the collection chamber when the pressure
within the chamber is higher than atmospheric but which otherwise
prevents the passage of air from the atmosphere to the collection
chamber. When the drainage device is used with regulated suction,
a positive pressure release valve is included to prevent the build-up
of excessive positive pressure within the device in the event of
failure of the suction pump or in the event of a sudden, very high
pressure surge within the pleural cavity.
Additional features and advantages of the present invention will
be apparent from a consideration of the following detailed description
of the preferred embodiments of the invention in connection with
the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the two-chambered underwater drainage
device with a flow meter according to the present invention.
FIG. 2 is a front cross-sectional elevation view of the of the
drainage device depicted in FIG. 1 taken along line 2--2.
FIG. 3 is a front cross-sectional elevation view of an alternative
embodiment of a drainage device with a flow meter.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now more specifically to the drawings where like numerals
are used to represent like elements throughout the several views,
there is depicted in FIGS. 1 and 2 an underwater drainage device
10 that comprises a housing 12 which may be formed of a rigid transparent
plastic material or the like. Housing 12 is depicted in the present
embodiment in a substantially box-like shape having four vertical
walls when in the upright position, namely a front wall 14 a rear
wall 16 a first end wall 18 and a second end wall 20. In addition,
housing 12 is provided with a top wall 22 and a bottom wall 24.
Underwater drainage device 10 is also provided with an inlet 26
for attachment to a thoracotomy tube which extends into the patient's
pleural cavity. An outlet 28 is adapted to connect housing 12 with
a suitable source of suction. Housing 12 is further provided with
a first opening 30 in the upper portion of first end wall 18 and
a second opening 32 located adjacent outlet 28. Grommets 34 and
36 respectively, are disposed in first opening 30 and second opening
32. Removable covers 35 and 37 are positioned in sealing engagement
with container 12 over respective grommets 34 and 36.
As shown in FIGS. 1 and 2 an internal inlet tube 38 extends downwardly
from drainage device inlet 26 and terminates at a sloping main partition
40. Main partition 40 extends horizontally from first end wall 18
toward second wall 20 and transversely from front wall 14 to rear
wall 16 to divide drainage device 10 into an upper underwater seal
chamber 42 and a lower collection chamber 44. One corner of main
partition 40 located below inlet tube 38 is provided with a U-shaped
recessed portion 46. Recessed portion 46 is defined by a cup portion
48 having a semicircular side 50 attached to a circular bottom 52.
The other side of cup portion 48 is formed by front wall 14.
Cup portion 48 is located and sized so as to satisfy two, somewhat
conficting criteria. The purpose of cup portion 48 is to retain
liquid drained form the pleural cavity so that after a predetermined
amount of liquid has been drained and the bottom of inlet tube 38
is covered, a seal is automatically formed. Thus, one criterion
is that cup portion 48 be small enough so that only a relatively
little amount of liquid need by drained from the pleural cavity
of the patient before a seal is formed. On the other hand, it is
an important feature of the present invention that the seal, once
formed, is not destroyed by the inadvertent tilting of drainage
device 10. Hence, cup portion 48 should have a sufficiently large
enough capacity so that should some liquid be lost therefrom, the
seal will not be broken. Obviously, the bottom of inlet tube 38
can extend downwardly into cup portion 48 to aid in preventing the
loss of a seal if drainage device 10 becomes tilted. However, this
has a disadvantage in that the greater the height of the liquid
up inlet tube 38 the greater the differential in pressure will
be between the pleural cavity and the seal chamber. Therefore, in
a presently preferred embodiment of the present invention, the bottom
of inlet tube 38 extends only to the bottom of main partion 40.
As mentioned above, main partition 40 is sloped from a position
nearer second end wall 20 to first end wall 18. Thus, main partition
40 is spaced at a greater distance from top wall 22 adjacent end
wall 18 than at the position nearer second end wall 20. The sloping
of main partition 40 permits the liquid accumulating in seal chamber
42 to flow in the direction of cup portion 48 thereby tending to
keep cup portion 48 filled upon a minor tilting of drainage device
10.
Located substantially centrally in main partition 40 is an opening
54 for permitting the flow of fluid (i.e., both liquid and gas)
from underwater seal chamber 42 into collection chamber 44. As shown,
means surrounding opening 54 is provided to prevent a substantial
loss of liquid from underwater seal chamber 42 into collection chamber
44 should drainage device 10 be tipped. This means includes a U-shaped
baffle 56 that extends between main partition 40 and top wall 22.
The open end of baffle 56 faces first end 18 and is aligned substantially
parallel therewith. A gate 58 is connected at each end to the open
ends of baffle 56 and is also connected at the bottom to main partition
40. Gate 58 extends upwardly a predetermined distance toward top
wall 22 such that the depth of liquid in underwater seal chamber
42 when drainage device 10 is in the normal upright position, is
determined by the height of gate 58. Thus, as soon as the liquid
drained from the pleural cavity accumulates in underwater seal chamber
42 to a depth greater than the height of gate 58 the extra liquid
flows over gate 58 through opening 54 into collection chamber 44
below. A drip ledge 60 is located on the underside of main partition
40 directly below the bottom of gate 58. Drip ledge 60 permits a
more efficient flow of the overflow liquid from underwater seal
chamber 42 into collection chamber 44. As shown in FIG. 1 a notch
62 can be centrally provided in gate 58 so as to more accurately
control the depth of the reservoir liquid in underwater seal chamber
42.
A vertical partition 70 is attached to the end of partition 40
near second end wall 20. Vertical partition 70 extends transversly
between front wall 14 and rear wall 16 and vertically extends between
top wall 22 and a floor 72. Floor 72 extends horizontally from vertical
partition 70 to second end wall 20 and from front wall 14 to rear
wall 16. Vertical partition 70 and floor 72 form a corner chamber
in housing 12 which is further subdivided by a second vertical partition
74 parallel to vertical partition 70 and a transverse partition
76 located between vertical partition 70 and second vertical partition
74. As shown best in FIG. 1 this forms three separate chambers
in the corner of housing 12: a flow chamber 80 a connecting chamber
82 and an outlet chamber 84.
Fluid communication is provided between upper seal chamber 42 and
flow chamber 80 by a channel passageway 86. As shown best in FIG.
1 passageway 86 extends along top wall 22 from one end which is
located above gate 58 through baffles 56 to the other end which
terminates at vertical partition 70.
Disposed along front wall 14 in flow chamber 80 is a flow meter
90. Flow meter 90 includes an enclosed elongate column 92 extending
in a generally vertical direction. The horizontal cross-sectional
dimension of column 92 increases gradually in size upwardly over
the length thereof. It should be noted that the lower end of column
92 is spaced slightly above floor 72. The upper end of column 92
is fluidly connected to a second channel passageway 94. As shown
in FIG. 1 second channel passageway 94 extends from column 92 along
top wall 22 to transverse partition 76.
Connecting chamber 82 lies below grommet 36 which is positioned
in top wall 22. Thus, access to connecting chamber 82 can be provided
through grommet 36 when desired. One-way fluid communication out
of connecting chamber 82 and into outlet chamber 84 is provided
through a suitable one-way valve 96 located on second vertical partition
74. Disclosed in one of the applicants' prior U.S. Applications,
Ser. No. 107329 filed Dec. 26 1979 and entitled DRAINAGE DEVICE
WITH SEPARATE OUTFLOW CHAMBER now U.S. Pat. No. 4312351 issued
Jan. 26 1982 and Serial No. 120295 filed Jan. 11 1980 and entitled
TWO-CHAMBER UNDERWATER DRAINAGE APPARATUS WITH ONE-WAY OUTFLOW VALVE
now U.S. Pat. No. 4324244 issued Apr. 13 1982 incorporated herein
by reference, is a suitable construction for a one-way valve 96.
As shown by these prior applications and in FIGS. 1 and 2 a central
orifice 98 and four peripheral orifices 100 extend through second
partition 74. One-way valve 96 has a stem 102 that is mounted in
central orifice 98 and an enlarged head 104 that extends over peripheral
orifices 100. Thus, when pressure in underwater seal chamber 42
collection chamber 44 flow chamber 80 and connecting chamber 82
exceeds the pressure in outlet chamber 84 head 104 of one-way valve
96 is forced away from second vertical partition 74 so as to permit
the passage of gases into outlet chamber 84 and to equalize the
pressures therebetween. However, when the pressure is higher within
outlet chamber 84 than within the rest of drainage device 10 one-way
valve 96 remains closed preventing fluid communication in the opposite
direction. For convenience, a suitable aperture 106 located in second
end wall 20 is provided for inserting head 104 into position on
second vertical partition 74. Aperture 106 is then sealed by a cover
108.
Outlet chamber 84 is fluidly connected to a suitable source of
suction or to the atmosphere through outlet 28 in top wall 22 which
is positioned above outlet chamber 84. Extending downwardly from
top wall 22 and into outlet chamber 84 is a positive pressure release
valve 110. The purposes for and the detailed structure of release
valve 110 are described in greater detail in the aforementioned
pending patent applications of one of the inventors. Release valve
110 includes an enclosed valve chamber 112 having a bottom 114 with
an aperture 116 therein. A ball 118 is located in valve chamber
112 and is normally seated on aperture 116. Fluid communication
is provided between valve chamber 112 and the outside atmosphere
through two valve outlets 120 in top wall 22 located above valve
chamber 112. The purpose of positive pressure release valve 110
is to provide a means for release of high positive pressure to atmosphere
in the event very high pressures are reached within collection chamber
44 underwater seal chamber 42 flow chamber 80 connecting chamber
82 and outlet chamber 84 and the device is operated with a vacuum
pump which is malfunctioning or unable to provide release for such
high pressure. Normally, ball 118 remains seated over aperture 116
to maintain release valve 110 closed and release valve 110 opens
only in response to pressures within drainage device 10 in excess
of atmospheric pressure.
When drainage device 10 is used, it is normally used with a suction
attached to outlet 28 from a controlled suction device. However,
in some cases, drainage device 10 can also be used without a suction.
In either case, drainage device 10 is used without prefilling the
fluid seal. A thoracotomy tube (not shown) is connected between
the pleural cavity of the patient and inlet 26. One-way outlet valve
96 protects the patient from the admission of atmospheric air with
the resulting danger of pneumothorax. The liquid secretions from
the pleural cavity initially fill cup portion 48 to provide an underwater
seal at the lower end of inlet tube 38. When cup portion 48 is filled
with liquid, the liquid overflows onto the top of main partition
40 Initially, accurate measurements of the liquid secretion can
be made inside cup portion 48 which can be calibrated.
In the event that suction is used, the hose from a regulated suction
source is attached to outlet 28 and the desired degree of negativity
is maintained within collection chamber 44 underwater seal chamber
42 and the pleural cavity. When operated with suction, additional
protection is provided against possible buildup of positive pressure
within collection chamber 44 and the pleural cavity of the patient
by positive pressure release valve 90 which can open in the event
of sudden high pressure surges within drainage device 10.
In the use of drainage device 10 wherein the underwater seal is
formed directly at the end of internal inlet tube 38 by the liquid
secretions from the pleural cavity of the patient, it is important
that drainage device 10 be constructed so that excessive negativity
within the pleural cavity, such as might by caused by blockage in
the bronchial tubes or the like, cannot cause the fluid within the
underwater seal to rise within inlet tube 38 and into the throacotomy
tube and pass back into the pleural cavity. This is precluded in
the presently disclosed apparatus because of the incorporation of
one-way valve 96.
As drainage device 10 operates to collect fluids from the pleural
cavity, gases which are passed from the pleural cavity into device
10 through inlet 26 are subsequentally conducted out of drainage
device 10. These gases pass through channel passageway 86 into
flow chamber 80 into flow meter 90 and the bottom of column 92
out of the top of column 92 into second channel passageway 94 into
connecting chamber 82 through one-way valve 96 into outlet chamber
84 and finally out of drainage device 10 through outlet 28. The
rate of flow of these gases is indicated by ball 118 which rises
in column 92. As discussed above, column 92 increases in cross-sectional
dimension upwardly so that ball 118 rises to a height in column
92 which is indicative of the specific rate of flow of gases through
column 92. The rise of ball 93 is visible through front wall 14
so that the rate of flow of gases through drainage device 10 is
easily discernable. The rate of flow of gases is important in determining
whether drainage device 10 is functioning properly and whether an
air leak exists in the pleural cavity of the patient. Where an air
leak does exist in the pleural cavity of the patient, the greater
the flow of air through flow meter 90 the greater the air leak
present in the patient's pleural cavity.
If drainage device 10 is accidentally tipped or tilted, because
of U-shaped baffle 56 and the location of channel passageway 86
an inhibiting means is provided to prevent the flow of fluids from
underwater seal chamber 42 into flow chamber 80. The introduction
of liquids into flow chamber 80 would cause flow meter 90 to malfunction.
It sould be noted that during an accidental tilting, gate 58 blocks
the entrance of fluid through opening 54 in main partition 40 and
together with the sloping of main partition 40 assure that a sufficient
reservoir of liquid is maintained in seal chamber 42 to keep cup
portion 48 full of liquid and the seal intact.
Depicted in FIG. 3 is an alternative embodiment of the present
invention which includes a drainage device 10' which is similar
in many respects to drainage device 10. Thus, drainage device 10'
has a housing composed of a front wall, a rear wall 16', a first
end wall 18', a second end wall 20', a top wall 22', and a bottom
wall. Top wall 22' includes an inlet 26' and an outlet 28'. Depending
from inlet 26' is internal inlet tube 38'. Housing 12' is divided
horizontally by a main partition 40' to form an underwater seal
chamber 42' and a lower collection chamber 44'. Lower collection
chamber 44' is further divided into three collection wells by vertical
walls 45'.
Main partition 40' includes a recessed portion 46' having a cup
portion 48'. Main partition 40' is spaced from first end wall 18'
so as to provide an opening 54' between underwater seal chamber
42' and lower collection chamber 44'. Located adjacent opening 54'
is a gate 58' extending above main partition 40' and a drip ledge
60' located immediately below gate 58'.
In this embodiment, a vertical partition 70' and a floor 72' separate
a corner of housing 12' from underwater seal chamber 42' and lower
collection chamber 44'. A second vertical partition 74' and a trap
partition 75' further divide the corner of housing 12' into a trap
chamber 78', a flow chamber 80', a connecting chamber 82', and an
outlet chamber 84'. A channel passageway 86' running along the underside
of top wall 22' connects underwater seal chamber 42' with trap chamber
78'. Adjacent the end of channel passageway 86' and in the center
of trap chamber 78' is a drip ledge 88'. An air flow meter 90' having
a column 92' is disposed vertically in flow chamber 80'. The bottom
of column 92' is located adjacent, but spaced from, floor 72' while
the top of column 92' is open to connecting chamber 82'. Housing
12' is further provided with a one-way valve 82' and a positive
pressure release valve 110' similar to one-way valve 96 and release
valve 110 described above.
In use, drainage device 10' functions in the same manner as described
above with respect to drainage device 10. Thus, inlet 26' is connected
by a thoracotomy tube to the pleural cavity of the patient and outlet
28' is preferably connected to a suitable source of suction. As
fluids from the patient collect in cup portion 48', an underwater
seal is quickly formed with internal inlet tube 38'. As sufficient
liquid collects, additional liquid overflows gate 58' and is collected
in the first well in collection chamber 44'. In the mean time, gases
which are conducted through the thoracotomy tube pass through internal
inlet tube 38', into underwater seal chamber 42', into channel passageway
86', through trap chamber 78', into flow chamber 80', through flow
meter 90', into connecting chamber 82', through one-way valve 96',
into outlet chamber 84', and finally out of housing 12' through
outlet 28'. The rate of flow of the gases is determined by flow
meter 90' on the same manner as discribed above with respect to
flow meter 90.
Should housing 12 be inadvertently tilted towards first and wall
18 gate 58' acts to maintain the fluid in underwater seal chamber
42. Should housing 12 be tilted inadvertently in the other direction,
the fluid pools in the area between vertical partition 75' and main
partition 40'. Thus, with channel passageway 86' located along top
wall 22', the fluid in underwater seal chamber 42' is inhibited
from entering channel passageway 86' while still being retained
in underwater seal chamber 42'.
If liquid from underwater seal chamber 42' should inadvertently
enter channel passageway 86', the liquid continues along channel
passageway 86' until it drips into trap chamber 78'. To assure that
the liquid falls into trap chamber 78', drip ledge 88' is positioned
so as to prevent any of the liquid from being drawn directly from
channel passageway 86' into flow chamber 80'. Obviously, any liquid
collecting or impinging on drip ledge 88' falls into trap chamber
78'. The top angled portion of trap partition 75' also helps to
maintain any liquid in the gas flow exiting from channel passageway
86' from passing into flow chamber 80'. As the front wall of housing
12' is preferably made from a transparent plastics material, the
presence of liquids in trap chamber 78' is immediately viewable.
Thus, if any liquids are seen in trap chamber 78', the use of drainage
device 10' should be immediately discontinued and replaced with
a new drainage device 10' because of the danger of the liquid blocking
air flow meter 90' which could result in a tendin pneumothorax.
While drainage devices 10 and 10' can rest on their bottom walls,
it would also be possible to provide drainage devices 10 and 10'
with a hanger attachment to further stabilize the device or to allow
the device to be hooked on to a bedside. Such a hanger device is
also disclosed in the above mentioned pending applications.
Although the invention has been described relative to exemplary
embodiments thereof, it will be understood that variations and modifications
can be effected in these exemplary embodiments without departing
from the scope and spirit of the invention.
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