Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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~ Background
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This invention relates to fluid evacuators and, more
particularly, to such evaeuators which are disposable, portable
and substantially self-contained.
The evacuation of fluids from the body of a patient is a
common medical practiee. For example, the removal of fluids from
the vieinity of a wound has been found -to aid fas-ter and firmer
healing and reduce the likelihood of infection, fever and patient ..~.
diseomfort. Fluid evaeuation usually is accomplished through .
` 10 gravity drainage, pressure dressings, eompression bandages or by
negative pressure, the latter being preferred. Convèntional
eontinuous elosed wound suetion devices inelude power-driven
. vaeuum pumps, eentral suetion systems or evaeuated bottles.
`.j With the exeeption of the evaeuated bottle, each of these
systems has many disadvantages beeause of their eost, noise
.;. . and restriction of patient mobility resulting in the retar-
~t , dation of post operative exercises, ambulation and rehabill-
. tation. .
., Other suetion wound drainage systems were developed
to overcome these disadvantages. Examples of more recent
~ eommonly used wound evacuators are shown in U.S. Patent Nos.
:~' . 3,115,138 and 3,376,868. In both of these devices the evacuator
comprises an evacuation chamber formed with resilient side
. walls whlch, after manual compression and release, tend to
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return to their original extended position~ In so returning,
they provide a reduced pressure on the interior of the container
which, when attached to the patient by means of a tube, effects
evacuation of the wound. A potential hazard with several of
these devices is the possibility of accidental compression of the
container at a time when compression is undesirable. Accidental
compression when these devices are attached to the patient
could result in the injection of air or previously removed fluids
into the patient.
Another disadvantage with devices of this type is their
wide variation of negative pressure over the specified filling
range of the devices. When empty and fully compressed these
devices often provide a vacuum higher than necessary which might -
cause leasions if tissue is sucked into or against the drainage
` tube. On the other hand, as the container becomes filled with
fluid the vacuum is reduced often to c~ level where the vacuum
. .
is relatively ineffective an~ clots or other debris may clog the
`~ drainage tube. Wound evacuators presently commercially available
have total pressure variations of about 130% or more. ;
Accordingly, it is an objective of this invention
.
to provide an inexpensive, reliable, disposable, portable,
self-contained vacu-~m drainage device which evacuates fluids
from wounds at relatively constant pressure throughout the entire
operating range of the device.
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It is another objective of this invention to provide
an Improved self-contained wound evacuator which cannot be easily
accidentally pressurized or which will prevent accidental injec- -
tion of air or previously evacuated fluids back into a patient.
A still further objective of this invention is to provide
an improved wound evacuator which is adapted for use with an
external negative pressure source in order to provide continuous
fluid flow evacuation and which also includes its own negative
pressure source to form a totally self-contained unit.
lQ Additional objectives and advantages of the invention
will be set forth in part in the description which follows, and
in part will be obvious from the description, or may be learned
by practice of the invention. The objects and advantages of
the invention may be realized and attained by means of the instru- -~
mentalities and combinations particularly pointed out in the
appended claims.
Brief Description of the Invention
To achieve the foregoing objectives and in accordance
with`the invention in one aspect there is provided a fluid
evacuator comprising a container having an inlet passageway
and an outlet passageway communicating with the interior
thereof; an inflatable member within said container; means for
deflating said inflatable member; said inlet passageway being
adapted to receive a conduit, said outlet passageway being adapted
to be connected in fluid flow communication with a negative pres-
sure source; said container including first and second spaced apart
opposed side walls, and third and fourth side walls joined to the
opposite ends of said first and second side walls, said third and
fOurth side walls being spaced apart a distance greater than the
spacing between said first and second walls; said container having
at least one resilient wall capable of being deformed inwardly by
applying an external pressure thereon, said resilient wall having
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sufficient resilience to return to an undeformed state upon
release OI said exterlla~ ~ressure, said inflatable member within
said container being resiliently expandable between a natural state
and a resiliently enlarged deformed state, the interior surface of
said container and the exterior surface of said inflatable membex
defining a fluid-receiving chamber therebetween, said inflatable
member having an opening therethrough connecting the interior of
said inflatable member with the exterior of said container, said
opening including means for restricting flow through said opening
from said inflatable member; said inlet passageway being in flow
communication with said chamber for receiving said fluid; said
- outlet passageway being in flow communication with said chamber
and including a one-way valve preventing flow into said chamber;
; and said one resilient container wall being deformable inwardly
to flow air outwardly from said chamber through said container
outlet passageway to reduce the volume of said chamber, said
inflatable member being expandable from said natural state to its
resiliently enlarged deformed state by flow of air through said
opening into said member in response to return of said one container
- 2~ wall to its undeformed state and the reduced pressure generated
;`~ thereby in said chamber whereupon return of the inflatable member
to its natural state under force of its natural resilient bias flows
air outwardly of said member through said restricted opening and
produces a substantially constant negative pressure in said chamber
for drawing fluid through said inlet passageway into said chamber.
As a further feature the fluid evacuator includes means
for ensuring that a predetermined one of said inlet and outlet
passageways does not become obturated by said inflatable member
before the other of said inlet and outlet passageways.
As a further feature of the invention, means are provided
for inflating said inflatable member and comprising a resilient
squeeze bulb in flow communication with said opening and said flow
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restricting means comprising a one-way valve, said valve including
a bleed passage therethrough s~;d hleed passage having a diameter
significantly less than said opening.
According to a preferred form of the invention, said
opening is in flow communication with the atmosphere and said
flow restricting means comprising a one-way valve preventing flow
from said inflatable member, said inflatable member including
means to vent the interior of said member to the atmosphere to
deflate said member and generate negative pressure within said
chamberO
In the preferred form of the invention, the resilient
inflatable meI~er is a substantially cylindrical bladder.
In a preferred embodiment of the invention, said
first and second sidewalls have transverse outward curvature and
said third and fourth sidewalls have a radius of transverse
curvature which conforms to the shape of the natural, unimpeded
shape of the adjacent portion of said resilient inflatable member
during inflation of said inflatable member effecting substantially
constant negative pressure at said inlet during deflation of
said resilient inflatable member.
The accompanying drawings, which are incorporated in and
constitute a part of the specification, illustrate several embodiments
of the invention and, together with the description, serve to explain
the principles of the invention.
srief Description of the ~rawings
Of the drawings:
FIGURE 1 is a perspective view of a wound evacua-
tor formed in accordance with this invention;
FIGURE 2 is a sectional view taken along line 2-2
of FIGURE 1;
FIGURE 2A is a sectional view taken along line 2A-
2A of FIGURE 2;
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FIGURE 3 is a sectional view taken along line 3-3
of FIGURE l,
FIGURE 4 is an enlarged, partially cutaway,
perspective view of the throat portion of a pressurizéd air.
: 5 source formed in accordance with one form of this.invention.
. FIGURE 5 is an empirical pressure vs. volume curve
. of a cylindrical latex bladder within a rigid container
,~ formed in accordance with this invention~
FIGURE 6, with Figures 7 and 8, appears on the same
drawing sheet as Figure 4, is an enlarged sectional view of
a portion of the wall of the wound evacuator container
- having a roughened interior surface;
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FIGURE 7 is an enlarged sectional view of a
. portion of the wall of the wound evacuator container having
. a coating on the interior surface thereof;
1.5 FIGURE 8 is an enlarged, partially cutaway
perspective view of a pressu~ized air source formed in
accordance with a second form of this invention;
. FIGURE 9 is a partial sectiona~l view of`a wound
evacuator for~ed in accordance with.another embodiment of
this invention; : . ;
. . FIGURE lO is a top view of a wound.evacuator of
. FIGURE 9, .
FIGURE ll is a sectional view of an outlet port
used in the wound evacuator of FIGURE 9; ~:
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FIGURE 12 is a bo-ttom view of the outlet port of
FIGURE 11;
: FIGURE 13 is a sectional view of an inlet port
used in the wound evacuator of FIGURE 9;
FIGURE 14 lS a sectional view taken along line 14-
14 of FIGURE 13;
FIGURE 15 is a bottom view of the inlet port of
FIGURE 13;
: FIGURE 16 is a sectional view of a combined inlet--
outlet port;
FIGURE 17 is a cross-sectional view of another embodi-
ment of the invention;
FIGURE 18 is a cross-sectional view of the embodiment
of FIGURE 17 along lines 18-18;
FIGURE 19 is a cross-sectional view similar to
that of FIGURE 18 showing the deformed resilient sidewalls;
. FIGURE 20 is a cross-sectional view similar to
that of FIGURES 18 and 19 showing the in-Elation of the
inflatable member as a result of the deformation of the side-
walls.
FIGURE 21 is a cross-sectional view of another .
. embodiment of the invention.
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Detailed Description
of Preferred Embodiments
Throughout the spec1fication and claims, terms
of orientation, such as front, back, up and down are employed
with respect to the orientation shown in the drawings in
; order to simplify description of the invention and are not
; intendèd to limit the location or direction of the elements
with respect to which these terms are used. -
In accordance with the invention, the wound
evacuator includes a housing and a first port serving as
a fluid inlet port communicating with the interior of the
housing. The first port is adapted to receive a tube
designed to be placed internally within a patient adjacent
to a wound in order to remove fluids from the vicinity of
i 15 the wound. As here embodied, a selE~contained wound
¦ evacuator 10 is formed with a container 12 having opposed
firs-t and second side walls 16, 18 (hereinafter called
; front and back walls~, opposed third and fourth side walls20, 22 adjacent to the front and back walls 16, 18 and a
bottom wall 24. The container 12 is relatively rigid,
which means that it will not deform substantially when it
is subjected to the normal forces to which devices of this
sort are expected to be exposed. The container 12 is pro-
vided with at least one port, such as port 26, extending
-through and communicating wit -the interior oF the container
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: 12. The port 26 is adapted to receive flexible tubing 28
which is to be inserted into a patient adlacent-to the
wound being treated. The tubing 28 is conventional wound
tubing which is non-toxic, non-pyrogenic, inert, non-
porous and non-degradable when used in i-ts intended environ-
ment and which has a plurality of openings 29 at its distal
end.
While a single port 26 is sufficient for operation
.: of the self-contained wound evacuator 10 as described
below, it is preferred that a second port 30 be provided
to serve as an outlet port to permit expulsion of air
contained within the container 12 and to permi-t removal of
fluid which is received within the con-tainer 12 during
utilization of the wound evacua-tor 10. A suitable closure
or cap 32 is provided to permit selective opening and
closing of the second port 30.
: In accordance with the invention an air inflatable
member is mounted within the container 12 and means for
infIating and deflating the inflatable member are provided.
As here embodied, the inflatable member is a resilient
bladder 40 having an opening at one end 42 thereof. A means
for inflating the bladder 40 preferably is a manually
~: ` operated pump, such as a hand-operated bulbous resilient
member having a resiliency at least only sligh-tly greater
than the resiliency of the bladder 40. Such a resilient
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member is a rubber bulb 44 having an air inlet 46 and an
open neck 48. The open end 42 of the bladder 40 is mounted `
'. in the neck 48 of the bulb 44'so that air expelled through
the bulb neck 48 is forced to enter the bladder 40. While
the bladder can be mounted directly on the walls of the .
bulb neck 48, the embodiment illustrated in FIGURES 2 - 4 . .:::
: employs a plug 50 which is force-fitted within the neck 48.
the plug 50 having an air passageway 52 axially therethrough.......... . ~
The pluy 50 is provided with.an annular recess 54 to receive : -
the open end 42 of the bladder, the open end of the bladder
being trapped between the exterior of the plug 50'and the'
interior oE the bulb neck 48 to fixedly hold the bladder . ~:
in place. The bulb`44 serves as the means to infla-te the `
. bladder 40 while the resiliency of the bladder serves as .-
the means for defIating the bladder. '
¦ While the bulb air inlet 46 is shown at the top
of the bulb 44, it could be located at any other'position.
For example, with the container 12 as shown, locating the alr
. inlet on the side has been found particularly convenient
because it is easier to block the air inlet 46' with a finger
or the heel of a hand. Furthermore, in order to ensure
quick opening of the inlet 46' on release of the bulb so .
. that the bulb quickly refills with air entering through
the inlet 46' rather than being withdrawn from the bladder .
40, an irregular surface,'such as a bead 51 is provided
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through which the inlet is formed. The bead 51 prevents the
finger or hand from sealing the inlet during re-turn
of the bulb to its normal unsqueezed condi-tion.
Further in accordance with the invention, valve
means are provided which are responsive to the difference
in pressure between the bulb 44 and the bladder 40 so that
when the pressure in the bulb exceeds the pressure in the
bladder, the valve means permit free flow of air from the
bulb to the bladder. However, when the pressure-ln the
bladder 40 exceeds the pressure in the bulb 44, the valve
means restrict the flow rate from the bladder to a pre- -
determined minimal quantlty.
In order to control the rate of deflation of the
bladder 40, a slow leak check valve, such as a flapper
valve 56 having a small diameter bleed vent 58 -therethrough,
is mounted on the bladder side oE the plug 50. When the
bulb 44 is squeezed, the flapper valve 56 permits air to
be expelled freely from the bulb into the bladde~r 40 since
the pressure differential across the flapper valve 56 durin~
such an operation forces the flapper valve away from the plug
50 thereby~-permitting air to flow easily into the bladder 40.
However, when the bladder is at least partially inflated
` and the bulb 44 is returning from its squeezed or collapsed
position to its normal or expanded position, the pressure
within the bladder is higher than -the pressure within the
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bulb and the flapper valve is forced against the plug 50
thereby obturating the air passageway 52 except for the
vent 5~ and preventing most of the air from leaving the
. bladder 40. After the bladder is inflated and the wound
tubing 28 is inserted in a patient for evacuation, the small
bleed vent 58 permits air to be expelled from the bladder 40
. throuyh the passageway 52. .
. . To utilize the self-contained wound evacuator
. 10 of this inven-tion -the distal end of.-the wound tubing .
28 is inserted in the patient before the proximal end is
connected to the container 12 and closed by a conventional
. pinch clamp. The closure 32 lS removed from the outlet port
30 and the hladder 40 is infla-ted by alternately squeezing
and releasing the bulb 44. When squeezing the bulb 44 the
user covers the air inlet 46 to prevent air :Erom being expelled
through the .inle-t, thereby requiring that all air expelled
from the bulb 44 passes through the air passageway 52.into
. the bladder 40. When the bulb is released air enters the bulb
through the inlet 46. The flapper valve 56 prevents a substantial
20 amount of air from flowing from the bladder 40 back into the bulb
: 44. Continued pumping of the bulb infl:ates the bladder 40
which forces the air within the container 12 out thro~gh -the out-
let port 30 until such time as the inflated bladder substantially
: . - fills the container 22. At that time, -the proximal end of .
~:: 25 the wound tubing 28 is connected to the inlet port 26 (or the
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pinch clamp is opened) and ~he c1Osure 32 ia placed in the
outle-t port 30 thereby closing the port. As the bladder
deflates, the air in the bladder passes.outwardly through
: the bleed vent 58, the air passageway 52 and -the bulb air
: 5 inlet 46. Deflation of the bladder 40 produces a negative
pressure at the port 26 which causes fluids in the vicinity
of the openings 29 at the distal end of the wound tubing 28
to pass through the tubing into the container 12.
. After the container 12 is filled with body fluid,
the closure 32 is removed from the port 30 and the container
; is emptied, either by gravity feed (pouring the fluid out
through the port) or by attaching the port 30 to the.low
pressure side of a pump and pumping the fluid out. The body
; . fluid can also be expressed from the container 12 by closing .
the pinch clamp and pumping the bulb 44. As the bladder
inflates, it forces the body fluid out of the container and,
when empty the bladder is fully inflated and the wound
. evacuator.10 is ready.for reuse. If only a single port 26
. is used,-.the container is drained through the port 26.
: 20 In order to provide substantially constant.nega-
. tive pressure at the inlet port 26 throughout the entire .
.~ operating range.of the wound evacuator 10, and to utilize
substantially the entire volume of the container, the container 12
. and the bladder 40 should have a combined actual or effective
25 configuration so that the container does not physically interfere
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llOlZ~36
with or distort the inflation of the bladder 40 in at least
one direction of inflation. The terms "constant pressure"
and "substantially constant pressure" as used throughout ~
this specification and in the claims are intended for use in
a relative sense and do not imply absolute constant or unchanging
pressure. For example a total pressure variation of up to
about 20~-306 throughout about 90% of the deflation range is
acceptable.
A low profile container 12 (relatively narrow from
front 16 to back 18) is preferred because it can be more
confortably and conveniently worn by a patient or attached
to a support, such as a bed or chair. These advantages can
be obtained if the front and back walls 16, 18 are substantially
flat and relatively closely spaced apart. Substantially
flat front ànd-back walls are walls which either are truly
flat or which have a radius of curvature much greater than
the radius of the bladder 40 when the bladder contacts the
front and back walls 16, 18. Where a substantial vacuum is
to be induced in the container 12, it may be preferred -to
form the front and back walls 16, 18 with a shallow outward
curvature llarge radius of curvature) to provide structural
- strength without adversely affec-tlng the low profile of the
container. -
It also is desirable to be able to stand the container
12 vertically on a flat sur}ace, and, therefore, the bottom wall
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24 of the container preferably should be fla-t. .
It has been found that satisfactorily constant
pressure can be obtained with a cylindrical bladder when the
bladder is inElated in a low profile container ("flat" front
and back walls) if -the side walls 20, 22 adjacent to the
"flat" front and back walls 16, 18 actually or effectively
conform to the shape of -the inflated bladder 40.
In order to actually conform the side walls 20, 22
to-the-bladder shape, the side walls 20, 22 are Eormed with
a transverse outward curva-ture (from front wall to back
wall) as can be seen in FIGURE 2~. Prefcrably, the radius
of transverse curvature is Wc/2 where W is the distance
between the front and back walls 16, 18. It is also desirable
to avoid corners at the top and bottom of the side walls
and, therefore, rounded upper and lower ends are formed or,
alternatively, the side walls 20, 22 can be formed with a
longitudinal curvature from top to bottom as can be seen in
FIGURES 1 and 2.
While satisfactory results can be obtained over
a relatively wide range of front-to-back wall spacing, more
consistently re].iable results and more useful filing volume
for a given container slze while maintaining relatively con-
stant pressure can be obtained if the front and back walls
16, 18 are spaced apart a distance greater than twice the
diameter of the uninflated bladder (Wc 2Df).
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; In accordance with this invention, insteacl of
actually conforming the side walls 20, 22 to the inflated
bladder shape, the side walls 20, 22 can be made to "effec-
tively" conform to the bladder shape by controlling the
pressure within the container. More specifically, with
inlet port 26 closed as the bladder 40 is inflated, the air
inside the container 12 is expelled through the outle-t port
30 until the bladder ceases to expand within the container.
; After the bladder contacts the side walls 20, 22 and continues
-to inflate, it reaches a position within the container
wherein the bladder is about to be forced into a shape which
is different from what it would be if the side walls 20, 22
were nonexistent. At that -time, the outlet por-t is occluded
by the bladder to prevent further expulsion of air from the
container 12. Any further pressurization of the bladder 40
~` by pumping -the bulb 44 results in a concommitant increase in
pressure inside the container since the air cannot escape.
Upon release of the bulb 40 the pressure in -the bladder and
container drops to atmospheric pressure by virtue of the escape
of the air from the bladder 40 through the check valve bleed
port 58 and the bulb air inlet 46 at a predetermined rate to
the atmosphere. This concept of pressure equalization in the
container and bladder when the bladder is about to be deformed
into a shape which adversely affects the constant pressure
curve is referred to throughout the specification and claims
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as "effective" conformation of -the ~ontainer shape with the
bladder shape.
As herein embodied, the outle-t por-t 30 is occluded
by the bladder 40 when it reaches its predetermined shape.
This is effected by forming the outlet port 30 with an
inwardly ex-tending protuberance 31 which projects inwardly
an amount calculated to bring it in contac-t with the bladder
at the appropria-te bladder inflation level. The outlet port
30 and protuberance 31 can be formed as an in-tegral part of
the container 12 or i.t can be formed by a separate member
mounted in an opening formed in the container I2. When this
outle-t port-occluding concept is employed the shape of the
container 12 is not critical.
With respect to a container with ac-tually conforms
to the bladder shape and which has a satisfactory low profile,
substantlally constant negative pressure duriny defla-tion of
a bladder has been obtained with a container and la-tex
cylindrical bladder having the shapes generally shown in
FIGURES 2, 2A and 3 and having the followiny dimension ratios.
Df = dlameter of bladder;
I,f = length of bladder = 3.0 - 4.0 Df; -
W = width of container = 2.5 Df;
R = radius of transverse curvature of side
walls = Wc/2; .
Dc = length of container = 1.8 Lf;
P = container interior perimeter 22 Df;
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The bladder thickness (Ft) together with the
characteristics of the bladder material (actually, the
modulus of elasticity) determines -the vacuum level produced
within the container. Eor a latex bladder, a bladder thickness
of 0.01 Df has been found to produce a constant negative
pressure in the above described container of approximately
30 inches of water (see FIGURE 5). The container perimeter/
bladder diameter ratio is calculated to provide not greater
than a seven-fold increase in bladder perimeter which has
been found to be within a safe stress range for a latex
bladder. For a convenient and comfortable evacuator profile,
the bulb diameter (Db) should be approximately equal to the
width of the container (Db = W ).
These ratios provide a self-con-tained wound evacuator
lS having satisfactory performance by providing relatively
constant pressure in a desired pressure range ~-29 to -35
inches of`water) and a safe stress for a bladder made of natural
late~. The bladder can also be formed from any synthetic elas-
tomer, such a polyurethane. FIGURE 5 is a pressure vs. curve
of a latex bladder having a 3/4" uninflated dia~e-ter, a 2-1/2"
free length and a 0.012" walls thickness which was inflated in a
rigid container having dimensions substantially in accordance
with the above dimension ratios. As can be seen, the vacuum
within the container remains be-tween 31.3 inches of water at a
bladder volume of about ~.5 times the uninflated bladder volume
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(4.5Vl) and 29 inches of water at which time the bladder
first touched the relatively close container walls (e.g.,
16, 18). The pressure remains at this level throughout the
l operating range of the wound evacuator and satisfactory .
results have been obtained at bladder infla-tions of over
30Vl. The total pressure variation over -this range was only
about 8~ oE the minimum pressure within the range (29 lnches
of water). In connection wi-th wound evacuators, the pressure .
curve of FIGURE 5 is considered to have a substantially
; 10 constant pressure.
The container 12 can be formed of any suitable
material such a.moldable plastic, for example, polyvinyl
chloride. The shape of the container lends itself to being
blow molded; however,. it could be formed other ways, such as
by injection molding. At least a por.tion 59 of one oE the
flat side wa`lls 16, 18 preferably is transparent and a calibrated
~ graduated scale 60 is placed along the side thereoE to enable
-; . volumetric measurement oE the amount of fluid con-tained within
the evacuator 10. The container 12 also can be provided with
mounting tabs 61 to which a belt 62 or other support means is
~ a-ttached to facilitate hanging the wound evacuator 10 on a bed
: or chair or to enable the evacuator to be worn by an ambulatory
patient.
Further in accordance with the invention, it is
desirable to provide means for preventing accidental sealing off
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1 1~128~
of a portion of the container from the outlet port 30, especially
during evacuation of fluids from the container L2 which are
removed from the patient. One means for avoidi~g this blockage
is to provide a recess 63 (FIGURE 2A) in the interior surface
of the container walls, particularly in the area leading to
and adjacent to the outlet port 30. Such a recess 63 assures
the existence of a fluid flow passageway from the interior of the
container-12 to the outlet port 30. Also, the interior of the
container walls can be roughened, such as by injection molding
the container, -to accomplish -the same results (FIGURE 6).
A means for minimizing bladder 40 stress is to provide
a surface coating 64 on the interior surface of the container
12, (FIGURE 7) or on the exterior surface of the bladder 40,
which will lessen adherence of the bladder to the interior of
the container. For example, it has been found tha-t chlorinating
the surface of a latex bladder or coa-ting the interior surface
of a container with a conventional commercially available medi-
cal silicone fluid successfully lessens adherence of the bladder
to the container walls. Reduction of -the adherence of the
2Q bladder 40 to the container walls also is of substantial assis-
tance in maintaining the negative pressure substantially constant.
In order to operate the resilient bulb 44 illustrated
in FIGURES 2 and 3, it is necessary for the user to place his
finger over the air inle-t 46 while squeezing the bulb 44 to pre-
vent air from escaping through the air inlet 46 and thereby
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1101 86
forcing tha-t air into the inflatable bladder 40. The combined .
operation of simultaneously closing the air inle-t 46 and
squeeziny the bulb 44 is a safety feature to prevent accidental
. injection of air or previously removed fluid into the patient
since it is.unlikely that both steps will accidentally be
performed. Furthermore, the relative rigidity of the container
12 also precludes accidental pressurization of the contents
of the container 12 by pressing on the sides of the container.
Consequently, the structure provided by this invention
reasonably assures that fluid or air will not be accidentally
injected into the patient by accidental pressuring of the
container.
With some sacrifice in safety but to simplify the
utilization of the wound evacuator 10, another ~orm of resilient
15 , bulb such as bulb 66, illustratecl in FIGURE 8, may be used which
eliminates -the need Eor the operator to cover the air inlet.in
order to effectively inflate the bladder 40. An automatically
` operatlng check valve, such as a flapper valve 63, is located
. on the interior surface of the bulb 66 to normally cover the airinlet 70 and is provided with a small diameter bleed vent 72.
.: . In order to inflate the bladder 40 the user squeezes the bulb
66 thereby increasing the pressure within the bulb. This
: increased pressure forced the flapper valve 68 against the air
.~ . inlet 70 restric-ting the amount of air passing through the air
~, inlet t~ be at small amount whlch can pass through the bleed
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vent 72. The pressure differential across the flapper valve `
74 between the bulb 66 and -the bladder 40 causes the flapper
valve 74 to open and permit the air to freely enter the .
bladder 40.
Upon release of the bulb 66, the resiliency of the
bulb returns it to its original position increasing the
volume within the bulb resulting in a reduced pressure
: within the bulb. This produces a pressure differential
across the flapper valve 68 causing the flapper valve to -
open and allowing a-tmospheric air to enter the bulb through
: ¦the inlet 70 while closing the flapper valve 74 to preven-tescape of air from -the bladder. After the bladder 40 is
inflated sufficiently, and the bulb returns -to its normal
position, air leaving the bladder 40 flows through the bleed
vent 76 in the flapper valve 74, into the bulb 66 and through
. the bleed vent 72 in the flapper valve 68 and to the atmosphere.
. To further protect against accidental ejection of air -
or liquid through the port 26 and back into the wound, a check
valve, such as a flapper valve 80, can be mounted adjacent to
the port 26 for closing the port 26 upon pressurization of the .
: ¦container, such as if the bulb 44 (or bulb 66) is accidently
squeezed. Of course, the check valve 80 does not interfere .
with the flow of fluid into the container 12 through the wound
: . tubing 28. Furthermore, the port 26 can be formed such that the
bladder 40 occludes the port 26 when -the bladder is inflated to
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~ 1~ 2~
its intended volume to further ensure against leakage through
the port 26 to the patient.
It is also contemplated that a bulb can be used
which has the same capacity as a fully inflated bladder. In
S other words, a single compressi.on of the bulb would be
sufficient to complete the inflation of the bladder. With a
bulb of this size there is no re~uiremen-t for an air inlet
~6 and a closed system can be formed wherein air from the
bulb fills the bladder and, when the bladder deflates, the
air returns to the bulb for subsequent use. In such a
closed system, a supple bulb, less resilient than the bladder,
is used.
Further in accordance with this invention, the wound
evacuator is adapted for use with an external negative pressure
source, such as a conventional vacuum pump, in order to contin-
uously evacuate fluid from the patien-t. Thls permits a surgeon
to have the wound evacuator continuously fully operative while
he performs surgery and closes up the wound si-te. During this
period, there is no need to have a fully self-contained portable
wound evacuator and reliance upon a vacuum pump to provide the
negative pressure is not an inconvenience since the patient is
immobile on the operating table. However, upon completion of
the operation, the wound evacuator may be disconnected from the
external vacuum source and become a self-contained wound
~5 evacuator.
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1101;~86
For a wound evacuator which is adapted to be
attached to an external vacuum source, the inlet and outle-t
ports should be designed so that the inlet port does not
become closed or sealed by the bladder prior to sealing o~
the outlet port. Otherwise, the external vacuum source
could be operating without effecting removal of fluid from
the patient. When the wound evacuator container is properly
¦ shaped to actually conform to the bladder shape and provide
substantially constant negative pressure during deflation of
the bladder as is described above, it is preferred that the
inlet and outlet ports not be sealable from each other, or
in other words, that neither of the inlet or outlet ports be
sealed prior to the other, in order to ensure continuous fluid
flow between the inlet and outlet. When the container is other
than ideally shaped, such as is described above with respect to
forming the container to "eEfectively" conEorm to the bladder
shaped by cont~olling the pressure within the container, it may
be desirable to have one of the ports sealable by the bladder
either separately or simultaneously with the other port. For
example, by suitable positioning of the outlet port, the bladder
: could be inEiated and seal the outlet port prior to the bladder
being distorted from its free, unrestric-ted or unimpeded ex-
pànsion shape.
In accordance with the invention, a wound evacuator
havlng inlet and outlet ports deslgned to control the sequence
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I l~lZE~6
~f sealing is illustrated in PIGURES 9 and 10. As he.e
embodied, a seif-contained wound evacuator 100 adapted for
use with an external vacuum source (not shown3 is formed
with a contalner 102 having an inlet port 104 and an outlet
S port 106 extending through and communicating with the interior
of the container 102. The inlet and outlet ports 104, 106,
may be individually formed as an integral part of the container
¦ 102 (as is illustrated in FIGURE 2) or may be formed as separate
members mounted in openings formed in the container 102 as
is illustrated in FIGURE 9.
An air~inflatable member, for example, a resilient
bladder 108 mounted on a means for inflating the bladder such
. as a hand-opera-ted bulbous resilient member 110, is mounted in
: an opening 109 through the conta~ner 102. The bulb 110 is pro-
15. vided with a suitable opening to receive external air and appro-
priate valve means are provided between the bulb 110 and the
bladder 108 to permit free flow of air from the bulb 110 to the . .
: bladder 108 when the bulb is squeezed to force air into the blad-
der 108 to the bulb 110 upon release of the bulb. Any suitable
imperfect check valve can be used for this purpose. For example,
a ball check valve 111 having either a roughened surface or a
-roughened valve seat would permit a limited flow rate from the
bladder 108 to the bulb 110. Another means is to provide a small
bleed passageway through or on -the side of the ball valve or
seat~ A similar imperfect check valve 112 can be used with the
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llU lZ86
l .
bulb 110 to permit free flow of air from the atmosphere in-to
the bulb and limi-ted flow rate of air from the bulb to the
atmosphere. This will enable the bulb 110 to fill quickly
and will force most of the air to flow into the bladder.
~s explained above wi-th respect to the embodiments
illustrated in FIGURES 1-8, the bladder 108 is expanded by
squeezing the bulb 110 and forcing air into the bladder, the
air between the bladder and the container interior walls
being forced out through an outlet port. When the bladder 108
is fully expanded, the outlet port 106 is closed by plug 128 and
air is permitted to leave the bladder through its check valve 111
at a controlled rate causing a reduced pressure -to exis-t at the
inlet port 104 providing the necessar~ suction to remove fluid
from the patient. I~hen the container 102 is full, it must be
emptied, the bladder reinflated, and the process repeated.
When it is desired to have continuous fluid evacuator
from a wound, the outlet port 106 of the fluid evacuator 100 is
attached for fluid flow communication with an external vacuum
source by means of flexible tubing 113 mounted on the outlet port
106. The inlet port 104, of course, is adapted to receive con-
ventional wound tubing 114.
To utilize the wound evacuator 100 as a continuous
evacuator, such as during an operation or closing of a wound, the
distal end ol the wound tubing 114 is inserted in the patient and
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81:
the interior of the wound evacuator container 102 is then
subjected to the negative pressure source, such as a vacuum
.' pump. Fluid from the wound freely flows into the container
102 through the inlet port 104 and it passes through the
outlet 106 to the vacuum source. This continuous fluid
evacuati~on con-tinues as long as required without the need
for intermittant emptying of the container 102 and reinflation
of the bladder 108. If the pressure within the container 102
. is reduced sufficiently below atmospheric pressùre, the bladder
108 will inflate as a result of air entering the bladder from the
atmosphere through the bulb 110 and bladder 108 passageways
between the bulb and bladder 108.
It is important to prevent the bladder 108 from sealing
. off the inlet port in order to ensure continued fluid-flow com-
! 15 munication between the inlet port 104 and the vacuum source throug
i the outlet port 106 and the container 102. Accordingly, suitablemeans must be provided to ensure that the inlet port 104 is not
obturated by the bladder 108. One means for preven-ting sealing
of the inlet port 104 is the formation of a discontinuous surface .
at the mouth 119 of the inlet 104. As here embodied, recesses or
notches 118 are formed at the mouth 119 of the inlet port 104 as
is best illustrated in FIGURES 13, 14 and 15. Similarly, in order
to preclude inadvertent sealing of the ou-tlet port 106 if so
desired, recesses or notches 116 are provided at the mouth 115 of
the outlet port 106 as is best illustrated in FIGURES 11 and 12. .
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l6
These notches 116, llg ensure continued fluid flow communi-
cation from the inlet port 104 to the outlet port 106.
For certain applications, it may be desired to
seal the outle-t por-t prior to the inlet port, or vice-versa.
In that case, the port which is desired to be sealed first would
not be provided with notches thereby permitting the bladder to
obturate the appropriate port. For example, if as described
above, the container 102 is not appropriately shaped to conform
to the unimpeded inflated shape of the bladder 108, an effective
configuration can be achieved by causing the bladder 108 to ob-
tura-te the outlet port 106 immediately prior to the moment when
the bladder is about to be deformed from its unimpeded expansion
. shape by virtue o.f contact with the container walls. Therefore,
the mouth o~ the outlet port 106 would not be provided with the
notches 116 allowing the outlet port to be obturated or sealed by
the bladder 108.
Another example for sea.ling the outlet port prior to the
inlet port would be to permit the bladder to serve as a regulator
: or limiting valve assuring a safe limit of vacuum being applied to
the inlet port 104. As the vacuum within the container 102
increases, the bladder 108 will inflate.and, if for some reason,
such as blockage of the inlet tube 114, insufficient flow of fluid
enters the container 102 theeby permitting the vacuum within the
container to continue to increase, the bladder will ultimately
~ ~expand tc ii the contalner anù seal the outlet valve, thereby
_ . ' '
;~
Z86
preventing fur-ther evacuation of the container 102. The
vacuum level at which the bladder would seal the outlet port
106 would be approximately the same as that which the bladder
itself would create in normal use if it was inflated by use
of the bulb 110 and, therefore, would be a safe vacuum
level. If outlet port 10~ is provided with means to prevent
sealing of this port by the bladder, then it is preferred
that a pressure regulator ~not shown) be provided in the
vacuum source line to assure a safe vacuum limit being
applied through the container 102 to the inlet port 104.
As is illustrated in FIGURES 13-15, -the inlet port
104 may be formed as a separate member such as by molding.
The inlet port 104 also includes a check valve 120 integrally
formed as a part thereof. The check valve is formed by
15 - molding a V-shaped wall or disc 122 across the inlet passageway
i 124 through the inlet port 104 and subsequently slitting theV-shaped wall at its apex thereby forming two flaps or lips.
In this manner, when the pressure differen-tial across the
check valve 120 is such that a lower pressure is in the
container 102 as contrasted with the inlet port passageway
124, such as when fluid is being removed from the patient,
the slit opens and fluid is permitted to pass therethrough.
However, if pressure within the container 102 exceeds the
pressure within the inlet port passageway 124, pressure will
tend to force the lips of the V-shaped wall together thereby
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1101~6
closing the slit and preventing fluid flow from the con-tainer 102
into the inlet passageway 124 and ultima-tely to the patient. The
check valve 120 is recessed with respect to the mouth 119 of the
inlet port 104 to ensure that the bladder 108 does not interfere
with the proper operation of -the check valve. An annular groove
126 also is formed near the mouth 119 o~ the inlet port 104 to
permi-t the inlet port 104 to be snap-fitted into an aperture
through the walls of the container 102.
The outlet port 106 also can be molded as a separate
member (FIGURES 11 and 12) and a closure plug 128 can be formed as
an integral part thereof. An annular yroove 130 is formed adjacen
the mouth 115 for mounting the outlet port on the container 102.
The inlet port 104 and the outlet port 106 may be
formed of any non-toxic, non-pyrogenic material suitable for
molding. One example of a suitable material is natural rubber~
Natural rubber also has the proper flexibility and resiliency
to make it ideal for proper operation of the check valve.
In place of using sepa~ate inlet and outle-t ports
and means such as grooves to control the sequence of closure
of the ports by the inflatable member, a combined inlet and
outlet port with separate passageways could be employed. Referrinc ,
~` to FIGURE 16, there is illustrated a Y-shaped combined inlet-outle1
- port 130 having an inlet passageway 132 through a neck 138 through
which the inlet and ou-tlet passageways communicate with the
interior of the container 102. A check valve 140 is formed or
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~otherwise mou-tcd across the lnlet pas~ag-way 132 anù an annular
groove 142 is formed on the outside oE the neck 138 to enable
the por-t 130 to be mounted on the container. An outlet port
closure plug 144 is formed on a strap integral with the port 130 tc ,
facilitate closing the outlet passageway 134 when the wound
evacua-tor is to be used as a self-contained unit.
Because only a single mouth or port entrance is
used for the combined inlet-outlet port 130, there is no danger
that one of the passageways 132, 134 could be obturated before
the other by the inflatable bladder 108.
Fluid may be evacuated continuously from a wound by con-
nec-ting the inlet passageway 132 to a wound by wound -tubing, and
the outlet passageway 134 with an extend vacuum source. After
the wound site is closed, the wound evacuator is disconnected
from the vacuum source and used as a self-contained evacua-tor
which fluid being collected in the container through use o~
the inflatable bladder.
In accordance with another embodiment of the invention,
and as best seen in FIGURE 17, the wound evacuator includes a
container 212-and a firs-t port serving as a fluid inlet port
communicating with the interior of the container 212, which con-
tainer is relatively resilient, which means that it will deform
l substantially when it is subjected to substantial external pressure .
~he first porl: is adapted to receive a tube deslgned to be placed
~ _ 3 ~_
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1101;:1~6
lnternally w~thln a ~a~ient adjacent to a wo~nd in order to rem~v~
fluids from -the vicinity of the wound. As here embodied, a self-
contained wound evacuator 210 is formed with the container 212
having opposed first and second side walls 216, 218 (hereinafter
called front and back walls), opposed third and fourth side walls
220, 222 adjacent -to the front and back walls 216, 218 and a .
bottom wall 224. The container 212 also is provided with at leas-t
one opening, such as opening 225, extending through and communi-
cating with the interior of the container 212. The opening 225 is
adapted to receive inlet and outlet means with the inlet and outle
means adapted to receive flexible tubing 28 which is to be inserte
into a patient adjacent to the wound being treated.
While a single opening 225 is sufficien-t for opera-tion
. of the selE-contained wound evacuator 210 as described below, it i ;
preferred that a second opening in the container be provided
for an outlet 230. Outlet 230 permits expulsion of air contained
within the container 212 and permits removal of fluid which is
received within the container 212 during utilization of the wound
evacuator 210. The outlet 230 should include a one-way valve
preventing flow into the container 212. A suitable closure or
cap 232 may be provided to permit selective opening and closing
of the outlet 230.
. While the embodiment of FIGURES 17 through 20 can be
utilized with the squeeze bulb 44 to inflate the bladder 40, the
bladder 40 can also be inflated by the deformation of the resilien
.
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containel 12. E'IGURES 1~ thlough 20 show the sequence of filling
the bladder 40 by deformation of the resilient container. FIGU~
18 depicts the apparatus in an undeformed state with the shape
of the bladder 40 assuming its natural shape. FIGURE 19 depicts
. the container 212 in the deformed condition where sidewalls 216
and 218 are deformed thereby reducing the volume of -the container.
The valve 56 prevents significant flow of air from the bladder 40.
FIGURE 20 shows the configuration of the bladder 40 subsequent
to the resilient recovery of the container sidewalls 216 and 218.
The exterior of the bladder 40 and the interior of the
container 212 form the fluid receiving chamber. The expulsion .
of air from the chamber and subsequent resilient recovery of the
container creates a difEerential pressure across the bladder 40
that draws air through the opening 52 to inflate the bladder 40.
A negative pressure is generated in the contai.ner 212 when the
bladder 40 is allowed to deflate, as for example, through the bleec .
. hole 58. It should be noted that while the shape o-f the container
212 depicted herein is preferred, other configurations of
containers would be operable with the present invention. Generally,
the container must have at~least one resilient wall capable of
being deformed and the container must have sufficient resilience
to return to the undeformed state upon the release of the pressure
deforming the container. .
. To utilize the self-contained wound evacuator 210
of this inventi.on, the distal end of the wound tubing 28 is inser-
. ~Y
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11C112~36
ted in the patien-t before the pro~imal end is connected to ~hè in-
let port 226. Alternatively, the wound tubing 28 can be connected
to the container 212 and closed by a conventional pinch clamp 27.
The closure 232 is removed from the outlet port 230 and the blad-
der 40 is inflated by alternately squeezing and releasing the bulb
44 or the resilient container 212.
As here embodied the container 212 has a separate inlet
and outlet, 226 and 230 respectively. The inlet depicted in
FIGURES 17 and 21 comprises a one-way valve 120, a preferred em-
bodiment of which is depicted in detail in FIGUXES 13, 14 and 15.
In the embodiment depicted, the inlet 226 only allows flow into
the container 212. The inlet 226 may also include inle-t valve
means, an example of which is the pinch clamp 27 previously dis-
closed. The inle-t valve means would be used to close the inlet
226 during inElation of the con-tainer 212 by the deformation of th~
resilient container walls.
The inlet 226 and the outlet 230 may also be located in
a common conduit that comprises the sole means of flow communica-
tion to the interior of the container 212. As depicted in FIGURE
21 the common conduit 90 is Y-shaped with the inlet 226 and outlet
230 located in separate branches of the Y. In such a configuratior
the inlet 226 preferably includes a one-way valve preventing flow
through the inle-t 226 from the container 212. In that manner the
container can be emptied without the possibility of collected -~
material passing from the con-tainer back into the tube 28. As
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llGlZ136
previously disclosed, the ou-tlet 230 must utilize a one-way valve
in all embodiments utilizing a resilient container.
FIGURE 21 depicts a preferred embodiment of the inven-
tion where the means of inflating the bladder 40 is solely the
deformation of the resilient container 212. In this embodiment
the opening 52 is in flow communication wi-th the atmosphere. The
flow restricting means in this embodiment is a one-way valve 256
comprising a flap valve without a bleed passage therethrough.
Means are provided to bypass the one-way valve to vent the interior
of the bladder 40 to the atmosphere thereby deflating the bladder
40 and generating the negative pressure within the container 40.
As here embodied and depicted in.E'IGURE 21, the venting
means comprises passage 92 with the associated manually controlled
vent valve here embodied as petcock valve 94. The venting means
depicted are not the only means of venting the bladder and one
skilled in the art can devise appropriate ventlng means wlth no
further specific teaching. For example, external means of forcing
flap valve 256 off its seat could be utillzed as the venting means
To utilize this embodiment of FIGURE 21 the inlet 226 or
20 - the tube 28 is closed to prevent airflow into the contalner 212.
The container is deformed lowering the volume within it and forcin~
the contents of the container out the outlet 230. Upon resilient
recovery of the container 212 the pressure within the container is
. lowered thereby drawing air into the bladder 40 past the one-way
valve 256 through -the open~ng 52. ~ultiple deformations of tho
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llOlZ~36
container 212 may be necessary to completely fill the bla~der 40
wi-thin the container 212. Once the bladder is sufficiently in-
Elated, ~he device may be utilized by opening the inlet 226 and
the valve 94 whereby the bladder 40 deflates through opening 92
creating a negative pressure in the container 212. It is pre-
ferred that the flow of air through the opening 92 be restrained,
thereby limiting the rate of negative pressure buildup wlthin the
. container 212. The most convenien-t means of controlling the flow
through opening 92 is by means of petcock 94. Also, one skilled
in the art may preselect the rate of negative pressure buildup by
preselecting the size of the opening 92.
Summary
, ..
It can be seen that the fluid evacuator of this inven-
tion is completely self-contained, portable and totally relia-
able, as well as being adapted for use with vacuum source as a
continuous evacuator. It is also easy and inexpensive to manu-
facture, and therefore, disposable. Of considerable significance
.. are the safety features which prevent the fluid evacuator from
being accidentally pressurized or otherwise prevent the lnjec-
tion of air or previously removed fluids back to -the patient.
. Furthermore, the negative pressure formed at the inlet port which
. causes the forced removal of fluid from the patien-t is substan-
tially constan-t thereby (a) avoiding p,tential i jury to the
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lli) lZ86
patient whic~ could occur it the negative pressure is too high
and (b) ensuring efficient operation of the evacuator -throughout
the entire operational range of the wound evacuator. .
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