Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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DUAL-FILTERED ISOLATION VALVE FOR RESUSCITATION
TECHNICAL FIELD
This invention relates to a valve which isolates a patient from a provider of
care when
such provider of care attempts to resuscitate such patient by forcing the
provider's breath into
the patient's lungs.
BACKGROUND ART
A variety of United States and foreign patents have been issued for devices
which
provide some degree of isolation between a patient and a care provider who is
attempting to
resuscitate the patient.
These include the following United States patents: 3,158,15?; 3,242,921;
3.923.054;
4,520,811; 4,811,730; 4,998,530; 5,005,568: 5,020,529; 5,146,914; 5.295,478;
and 5.357,951.
Similar foreign patents are the following: German (DDR) patent no. 53 856.
German (FDR)
patent no. 2 203 850. and French patent no. 2 664 167.
DISCLOSURE OF INVENTION
But none of these prior patents provides filters for all pathways that may be
taken by
breath exhaled by the care provider and the patient while having a path that
would enable the
often weak incipient breath of a patient to escape from the patient's lungs to
the atmosphere
even if the care provider is exhaling at the same time. Moreover, none of
these prior patents
2~ provides an air-tight seal while allowing rotation between the portion of
the valve to which a
mouthpiece may be attached for the care provider and the portion of the valve
to which a mask
or a mouthpiece may be attached for the patient--a movement essential for
maximizing
comfort for both patient and care provider during often lengthy attempts at
resuscitation.
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Increased comfort for the i:are provider will usually translate into bc}th a
longer period during
which resuscitation may he attempted and greater alertness of the care
provider during this
period. Finally, none of tile prior patents provides two filter segments in
the most direct
pathway between the patient and the care provider to minimize the possibility
of fluid passing
between the care provider and the patient while also establishing a space
between such filter
segments which is large ern~ugh to accommodate any fluid that manages to evade
one of the
filter segments without significantly obstructing the flow r.~f breath from
the care provider.
The primary pathway for the exhaled breath of the patient is through the
exhalation
filter to the atmosphere.
As its name implies, the Dual-filtered Rotary Isolation Val~-a for
Resuscitation filters
both the air exhaled by the provider of care and the air elhaled by the
patient. Moreover, the
path of exhaust air from the patient is not required to life any physical
object before reaching
the atmosphere; so, small, incipient breaths by a patient who had previously
ceased breathing
will not be retarded. Similarly, the usually stronger breath of the care
provider does not act to
i 5 close any aperture through which the patient's breath reaches the
atmosphere, even if both the
provider of care and the patient breathe simultaneausly.
To achieve low production costs and to minimize any slight potential for
failure, the
Dual-filtered Rotary Isolatiam Valve for Resuscitation has an extremely simple
construction.
There is an upper housing and a lower housing which snap together to permit
rotation to
achieve the most comfortable and efficient orientation of the upper housing
with respect to the
provider of care while simultaneously creating the most comfortable and
efficient orientation
of the lower housing with respect to the patient. Of course, the upper housing
is directed
toward the care provider: and the lower housing is directed toward the
patient. Preferably, the
provider of care will utilize a mouthpiece that may be attached to the upper
housing while a
mask may be connected to the lower housing for the patient.
There are only three other basic components: (a) a flexible diaphragm which
includes
a check valve, preferably a duck-bill valve, for precluding the exhaled breath
of the patient
from proceeding through the upper housing to the care provider and which, to
form an air-tight
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seal between the overlapping portions of the upper housing and the lower
housing (which
overlapping portions necessarily have some space between each other to effect
the desired
rotatability of the upper housing with respect to the lower housing) through
which the
unfiltered breath of the patient cannot pass, extends into the space between
the overlapping
portions of the upper housing and the lower housing; (b) a transmission
filter; and (c) an
exhalation filter.
The primary purpose of both the transmission filter and the exhalation filter
is to
prevent contaminants associated with bodily fluids of either the care provider
or the patient
from reaching the other person, i.e., either the care provider or the patient.
Since the most direct potential route for any such cross-contamination is
directly
between the upper housing and the lower housing, the transmission filter
intercepts this route.
Because the check valve precludes the exhaled breath of the patient from
proceeding through
the upper housing to the care provider. the preferred construction of the
transmission filter
minimizes the possibility of fluids passing from the care provider to the
patient, although it
also impedes the movement of fluids in any breath from the patient that may
manage to pass
the check valve. The transmission filter is constructed' with an upper filter
segment, which is
on the side of the transmission filter that is upstream with respect to air
coming from the care
provider, and a lower filter segment, which is on the side of the transmission
filter that is
downstream with respect to air coming from the care provider. Preferably, the
upper filter
segment is hydrophobic to repel any moisture in the breath from the care
provider. To create a
volume where any fluids that manage to evade the upper filter segment may
accumulate
without significantly obstructing the flow of the care provider's breath, a
ring spacer attaches
on one side to the upper filter segment and on its opposite side to the lower
filter segment.
(The center of the ring spacer is hollow to create the desired volume.) To
absorb fluids which
2$~ do enter the volume inside the ring spacer. the lower filter segment will
be hydrophilic.
Accordingly, in one aspect, the invention provides a dual-filtered rotary
isolation
valve for resuscitation of patients, the valve comprising an upper housing
having an
upper tube containing a bore formed by a surrounding upper tube wall, the
first end of
which upper tube may either be placed directly into a care provider's mouth or
be
connected to a mouthpiece to be placed into the mouth of the care provider,
the second
end of which upper tube expands outward to create a top of an upper chamber
segment
and then returns to its original direction to form a wall of the upper chamber
segment
having a circular cross section concentrically located with respect to the
cross section of
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the upper tube, the cross section of the upper tube also being circular, and
the wall of the
upper chamber segment protruding outward at a location between the top of the
upper
chamber segment and the bottom of the wall of the upper chamber segment to
create an
annular ridge, a lower housing having a lower tube containing a bore formed by
a
surrounding lower tube wall, the first end of which lower tube is in a
position selected
from the group consisting of being placed directly into the patient's mouth,
being
connected to a mask to be placed around the nose and mouth of the patient, and
being
attached to a mouthpiece to be inserted into the mouth of the patient, the
second end of
which lower tube expands outward to create a bottom of a lower chamber segment
and
then returns to its original direction to form a wall of the lower chamber
segment having
a circular cross section concentrically located with respect to the cross
section of the
lower tube, the cross section of the lower tube also being circular, the wall
of the lower
chamber segment bulging outward to create an annular channel at a location
between the
bottom of the lower chamber segment and the top of the wall of the lower
chamber
segment so aligned with the annular ridge in the wall of the upper chamber
segment that
the lower chamber segment can be snap-fit onto the upper chamber segment, the
inner
diameter of the wall of the lower chamber segment being slightly greater than
the outer
diameter of the wall of the upper chamber segment to permit the lower chamber
segment
to rotate with respect to the upper chamber segment, the inner diameter of the
annular
channel being slightly greater than the outer diameter of the annular ridge
but not so
much greater that the lower chamber segment could slip from the upper chamber
segment
once the lower chamber segment and the upper chamber segment have been snap-
fit
together, one or more apertures existing in the bottom of the lower chamber
segment, and
an annular step formed at the junction of the bottom of the lower chamber
segment and
the wall of the lower chamber segment, an exhalation filter placed on the
bottom of the
lower chamber segment, which exhalation filter contains an aperture that is
approximately aligned with the bore of the lower tube, a flexible diaphragm
having a
check valve near the center of the flexible diaphragm, having a support which
rests on the
exhalation filter adjacent to the support but covering only the outer edge of
the exhalation
filter so that the majority of the surface of the exhalation filter that is
opposite to the
bottom of the lower chamber segment is adjacent to a passage which
communicates with
the bore of the lower tube, and having an outer edge that extends into the
space between
the wall of the lower chamber segment and the wall of the upper chamber
segment with
3a
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the bottom of the wall of the upper chamber segment resting on the diaphragm
to create
an air-tight seal between the upper chamber segment and the lower chamber
segment,
and a transmission filter, the transmission filter filling the upper chamber
segment and
being.adjacent to the diaphragm.
BRIEF DESCRIPTION OF DRAWINGS
Figure 1 illustrates the Dual-filtered Rotary Isolation Valve with the valve
lips closed.
3b
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Figure ? portrays the Dual-filtered Rotary Isolation Valve with the valve lips
open.
Figure 3 shows the placement of two thin bands across the second end of the
upper
tube in the Dual-filtered Rotary Isolation Valve.
BEST MODE FOR CARRYING OUT THE INVENTION
The Dual-filtered Rotary Isolation Valve for Resuscitation, as illustrated in
Figure 1,
has an upper housing ( 1 ) and a lower housing (2).
The upper housing ( I ) is a unitary piece having an upper tube (3 j with a
bore (4)
formed by the surrounding upper tube wall (5). The first end (6) of the upper
tube (3) may go
IO directly into the care provider's mouth (not shown) or, preferably, is
connected to a
mouthpiece (not shown) io be placed into the mouth of the care provider. At
the second end
(7) of the upper tube (3), thL upper tube wall (S) expands outward to create
the top (8) of an
upper chamber segment (9) and then returns to its original direction to form
the wall (10) of
the upper chamber segment (9j. The cross sections of the upper tube (3) and of
the upper
1 S chamber segment (9) are both circular and are concentric with one another.
The lower housing (2) is a unitary piece having an lower tube ( 11 ) with a
bore ( 12)
formed by the surrounding lower tube wall (13). The first end (14) of the
lower tube (11 ) may
go directly into the patient's mouth (not shown] or. preferably, is connected
to a mask (not
shown) to be placed around the nose and mouth of the patient, or a mouthpiece
(not shown) to
20 be placed into the mouth of the patient. At the second end ( I 5 ) 01~ the
lower tube ( 1 1 ), the
lower tube wall ( 13 ) expands outward to create the bottom ( 16) of a lower
chamber segment
(17) and then returns to its original direction to form the wall (18) of the
lower chamber
segment ( I 7). The cross sections of the lower tube ( I l f and of the lower
chamber segment
( I 7) are both circular and are concentric with one another
2~ The inner diameter of the wall ( 18) of the lower chamber segment ( 1 T> is
slightly
greater than the outer diameter oil the wall ( 10) of the upper chamber
segment (9) to permit the
lower chamber segment ( 17) to rotate with respect to the upper chamber
segment (9).
Additionally. at a location between the bottom (16) of the lower chamber
segment (17) and the
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top ( 19) of the wall ( 18) c>f the lower chamber segment ( I 7 ), the wall (
18) of the lower
chamber segment ( 17) bulges outward to create art annular channel (20).
Similarly, at a
location between the top (8) of the upper chamber sel;ment {9) and the bottom
{21 ) of the wall
(10) of the upper chamber segment (9) aligned with the annular channel (20) in
the wall (18)
of the lower chamber segment (17), the wall ( 10) of the upper chamber segment
(9), protrudes
outward to create an annular ridge (22) which fits within the annular channel
(20) so that the
lower chamber segment {171 can be snap-fit onto the upper chamber segment (9).
Again,
however, to permit rotation of the upper chamber segment ( 9) with respect to
the lower
chamber segment {17), the inner diameter of the annular channel (2()) is
slightly greater than
the outer diameter of the annular ridge (22) but not so much greater that the
lower chamber
segment ( 17) could slip from the upper chamber segment (9) once the lower
chamber segment
(17) and the upper chamber segment (9) have been snap-fit together.
An exhalation filter (23 ) is placed on the bottom ( 16) of the lower chamber
segment
( 17). The exhalation filter ( 23 ) contains an aperture (24) which,
preferably. aligns with the
bore ( 12) of the lower tube ( 11 ). One and, preferably, more apertures (25 )
also exist in the
bottom ( 16) of the lower chamber segment ( 17).
At the junction of the bottom (16) of the lower chamber segment (17) and the
wall (18)
of the lower chamber segment ( 17) is formed an annular step (26). A flexible
diaphragm (27)
having a check valve (28) near the center of the flexible diaphragm (27) has a
support (29)
which rests on the exhalation filter (23) adjacent to the support (29) but
covers only the outer
edge of the exhalation filter .'23 ) so that the majority of the surface (30)
of the exhalation filter
(23) that is opposite to the bottom {16) of the lower chamber segment (17) is
adjacent to a
passage (31 ) which communicates with the bore { 12) of the lower tube ( 11 ).
The outer edge (32) of the flexible diaphragm (27) extends into the space (33)
between
the wall ( 18 ) of the lower chamber segment ( 17) and the wal l ( 10) of the
upper chamber
segment (9). Moreaver, the bottom (21 ) of the wall ( 10 ) of the upper
chamber segment (9)
rests on the diaphragm (27 f. Thus, the diaphragm (27) forms an air-tight seal
between the
upper chamber segment (9i and the lower chamber segment (I7).
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Filling the upper chamber segment (9) and adjacent to the diaphragm (27) is
the
transmission filter (34).
The transmission filter (34) has an upper filter segment (35) and a lower
filter segment
(36). The upper filter segment {35) is adjacent to the top (8) of the upper
chamber segment
{9); the lower filter segment (36) is adjacent to the diaphragm (27). An
annular spacer (37)
separates the upper filter segment (35) from the lower filter segment (36) and
thereby creates
air space (38).
When the care provider exhales into the upper tube {3). the breath of the care
provider
passes through the bore (4) of the upper tube (3), through the upper filter
segment (35),
through the air space (38), through the lower filter segment (36), through the
check valve (28),
through the bore ( 12) of the lower tube ( 11 ), and into the mouth and lungs
of the patient.
Since. as observed above. the path described in the immediately preceding
paragraph is
the most direct potential route for any contaminants associated with bodily
fluids to pass
between the care provider and the patient, the check valve (28) has been
inserted to preclude
1 ~ the patient's exhaled breath from traveling from the Lower tube ( 11) to
the upper tube (3)
Because the check valve (~ 8) necessarily permits the exhaled breath of the
care provider to
pass from the upper tube {3 ) to the lower tube ( 11 ) in order to accomplish
the desired
resuscitation of the patient. the transmission filter (34) is so constructed
as to minimize the
possibility of fluids passing from the upper tube (3) to the lower tube {1l),
although the
transmission filter (34) also impedes the travel of fluids from the lower tube
( 1 l ) to the upper
tube (3) in the event that any exhaled breath from the patient should manage
to pass the check
valve (28). The upper filter segment (35) is, therefore, preferably
hydrophobic to repel any
moisture in the breath from the care provider while the lower filter segment
(36) is preferably
hydrophilic to absorb any fluid that evades the upper filter segment (35) and
enters the air
?s space {38).
The air space (38). ~rthermore. creates a volume where fluids may accumulate
without
significantly obstructing the flow of the care provider's breath.
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As mentioned above, the check valve (28) is preferably a duck-bill valve. And,
preferably, the valve lips (3~>) axially extend into the bore (I2) of lower
tube (11) to maximize
the possibility that most of the breath exhaled by the care giver will travel
into lower tube { 11 )
rather than escaping into the passage (31) and then through the apertures {25)
into the
atmosphere.
On the contrary, when the' patient exhales, the exhaled breath from the
patient will pass
through the Lower tube ( 11 ), into the passage (31 ), through the apertures
(25), and into the
atmosphere. If the care provider is not exhaling into the Dual-filtered Rotary
Isolation Valve
at the same time as the patient exhales, the valve lips (39) will remain
closed so that the only
route available to the patient's breath will be that course describe in the
preceding sentence.
If, however, the care provider exhales into the Dual-filtered Rotary Isolation
Valve at the same
time as the patient exhales, the valve lips {39) will open. as illustrated in
Figure 2, only if the
breath from the care provider is stronger than the breath from the patient. In
such a case, the
patient's breath will still be able to follow the route described at the
beginning of this
paragraph and will not pass through the check valve (28) because of the
stronger fluid dynamic
force of the care provider's breath. With the valve lips ( 39) constructed so
that such valve Lips
(39) cannot open wide enough to reach the tube wall ( 13 ) of the lower tube
(1 I ), it is
improbable that breath of the care provider will be strong enough to force the
patient's breath
back into the patient's lung°,.
Since the patient's breath is likely to reach the atmosphere. the exhalation
filter (23)
intercepts the patient's breath before such breath passes through the
apertures (25). Preferably.
the exhalation filter (23) is hydrophobic to repel any fluids within the
breath of the patient.
The ability of the lower chamber segment ( 17 i to rotate with respect to the
upper
chamber segment (9) will, when a mouthpiece (not shown] is attached to the
first end (6) of
the upper tube (3) and a mask is connected to the second end {1 ~) of the
lower tube (11 j.
permit achieving the most comfortable and efficient orientation of the upper
housing ( 1 ) with
respect to the provider csf care while simultaneously creatinc the most
comfortable and
efficient orientation of the lower housing (2 ) with respect to the patient.
And. as mentioned
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previously, the extension of the diaphragm (27) into the space (33) between
the wall (18) of
the lower chamber segment ( 17) and the wall ( 10) c}f the upper chamber
segment (9) permits
the desired rotation while simultaneously creating an air-tight seal between
the upper chamber
segment (9) and the lower chamber segment (17) so that the patient's exhaled
breath cannot
_5 escape through the space (33 ).
Finally, as illustrated in Figure 3, to preclude damage to the transmission
filter (34)
while minimizing the resistance to the flow of air through the upper tube (3),
two thin bands
(40) are preferably placed parallel to one another across the second end (7)
of the upper tube
{3) and connected to the tube wall (5) of the upper tube (3 s.
INDUSTRIAL APPLICABILITS'
'I~he way in which the dual-filtered rotary isolation valve for resuscitation
is capable of
exploitation in industry and the way in which the dual-filtered rotary
isolation valve for
resuscitation can be made and used are obvious from the description and the
nature of the
1 S dual-filtered rotary isolation valve for resuscitation.
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