U.S. patent number RE43,886 [Application Number 12/931,599] was granted by the patent office on 2013-01-01 for apparatus for connecting a respiratory device with a patient.
This patent grant is currently assigned to Illinois Tool Works Inc.. Invention is credited to Jan W. Mijers.
United States Patent |
RE43,886 |
Mijers |
January 1, 2013 |
Apparatus for connecting a respiratory device with a patient
Abstract
An apparatus for connecting a respiratory device with a patient
is provided, including a breathing tube for insertion into a
patient's trachea, an inflatable cuff positioned around the
breathing tube, a connection tube connected to the cuff for
providing inflating air flow thereto, a pressurized air reservoir,
and a valve connected to the pressurized air reservoir and to the
proximal end of the connection line. The valve includes an entry
port associated with an entry differential force chamber, a first
exit port associated with a first differential force chamber and
coupled with the connection line, a second exit port associated
with a second differential force chamber and coupled with the
pressurized air reservoir, and a flexible membrane selectively
sealingly separating the differential force chambers. The flexible
membrane is configured to selectively connect the first and second
differential force chambers to maintain a substantially constant
air pressure in the cuff.
Inventors: |
Mijers; Jan W. (Heemstede,
NL) |
Assignee: |
Illinois Tool Works Inc.
(Glenview, IL)
|
Family
ID: |
34972483 |
Appl.
No.: |
12/931,599 |
Filed: |
February 4, 2011 |
Related U.S. Patent Documents
|
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
|
PCT/EP2005/006114 |
Jun 7, 2005 |
|
|
|
Reissue of: |
11633271 |
Dec 4, 2006 |
7717116 |
May 18, 2010 |
|
|
Foreign Application Priority Data
|
|
|
|
|
Jun 7, 2004 [DE] |
|
|
10 2004 027 734 |
|
Current U.S.
Class: |
128/207.15;
128/204.18; 128/207.14; 128/205.24 |
Current CPC
Class: |
A61M
16/044 (20130101) |
Current International
Class: |
A61M
16/00 (20060101); A62B 7/00 (20060101); A62B
9/02 (20060101) |
Field of
Search: |
;128/204.18,205.24,206.29,207.12-207.29 ;137/102,112,908
;604/509,98.01-102.03 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
1 009 834 |
|
Oct 1997 |
|
BE |
|
48105 |
|
Jun 1888 |
|
DE |
|
667 675 |
|
Apr 1934 |
|
DE |
|
1 695 553 |
|
May 1971 |
|
DE |
|
1 675 370 |
|
Sep 1971 |
|
DE |
|
25 02 673 |
|
Jul 1976 |
|
DE |
|
25 13 350 |
|
Oct 1976 |
|
DE |
|
27 13 618 |
|
Oct 1977 |
|
DE |
|
29 19 343 |
|
Nov 1980 |
|
DE |
|
30 35 301 |
|
Apr 1981 |
|
DE |
|
29 49 262 |
|
Jun 1981 |
|
DE |
|
82 14 927.5 |
|
Sep 1982 |
|
DE |
|
G 82 14 927.5 |
|
Sep 1982 |
|
DE |
|
32 15 329 |
|
Dec 1982 |
|
DE |
|
33 27 342 |
|
Feb 1985 |
|
DE |
|
34 35 900 |
|
Apr 1986 |
|
DE |
|
86 03 917.2 |
|
May 1986 |
|
DE |
|
G 86 03 917.2 |
|
May 1986 |
|
DE |
|
36 32 412 |
|
Mar 1988 |
|
DE |
|
48105 |
|
Jun 1988 |
|
DE |
|
38 03 380 |
|
Aug 1989 |
|
DE |
|
40 39 814 |
|
Jun 1992 |
|
DE |
|
92 09 491.0 |
|
Oct 1992 |
|
DE |
|
41 42 494 |
|
Jul 1993 |
|
DE |
|
42 01 258 |
|
Jul 1993 |
|
DE |
|
93 19 810.8 |
|
Mar 1994 |
|
DE |
|
G 93 19 810.8 |
|
Mar 1994 |
|
DE |
|
43 09 262 |
|
Jun 1994 |
|
DE |
|
43 04 949 |
|
Aug 1994 |
|
DE |
|
93 10 673.4 |
|
Sep 1994 |
|
DE |
|
G 93 10 673.4 |
|
Sep 1994 |
|
DE |
|
43 15 701 |
|
Nov 1994 |
|
DE |
|
295 01 239.0 |
|
Apr 1995 |
|
DE |
|
G 295 01 239.0 |
|
Apr 1995 |
|
DE |
|
691 09 240 |
|
Oct 1995 |
|
DE |
|
196 05 217.3 |
|
Feb 1996 |
|
DE |
|
G 196 05 217.3 |
|
Feb 1996 |
|
DE |
|
296 10 419.1 |
|
Dec 1996 |
|
DE |
|
G 296 10 419.1 |
|
Dec 1996 |
|
DE |
|
195 45 421 |
|
Jun 1997 |
|
DE |
|
196 43 360 |
|
May 1998 |
|
DE |
|
197 49 562 |
|
Apr 1999 |
|
DE |
|
195 45 421 |
|
May 2001 |
|
DE |
|
102 19 994 A10 |
|
Dec 2003 |
|
DE |
|
20 2004 009 831 |
|
Sep 2004 |
|
DE |
|
20 2004 009 521 |
|
Oct 2004 |
|
DE |
|
10 2004 053 214 |
|
Jan 2006 |
|
DE |
|
0 072 800 |
|
Mar 1983 |
|
EP |
|
0 379 047 |
|
Jul 1990 |
|
EP |
|
0 459 498 |
|
Dec 1991 |
|
EP |
|
0 562 246 |
|
Sep 1993 |
|
EP |
|
0 612 537 |
|
Aug 1994 |
|
EP |
|
0 612 537 |
|
Aug 1994 |
|
EP |
|
0 652 018 |
|
May 1995 |
|
EP |
|
0 812 596 |
|
Dec 1997 |
|
EP |
|
0 878 628 |
|
Nov 1998 |
|
EP |
|
0 887 085 |
|
Dec 1998 |
|
EP |
|
0 934 757 |
|
Aug 1999 |
|
EP |
|
1 063 956 |
|
Jan 2001 |
|
EP |
|
1 088 765 |
|
Apr 2001 |
|
EP |
|
1 093 828 |
|
Apr 2001 |
|
EP |
|
1 099 457 |
|
May 2001 |
|
EP |
|
1 239 145 |
|
May 2007 |
|
EP |
|
2 666 745 |
|
Mar 1992 |
|
FR |
|
439 278 |
|
Dec 1935 |
|
GB |
|
811 818 |
|
Apr 1959 |
|
GB |
|
2 027 168 |
|
Feb 1980 |
|
GB |
|
293686 |
|
Apr 1965 |
|
NL |
|
WO 88/02639 |
|
Apr 1988 |
|
WO |
|
WO 89/02764 |
|
Apr 1989 |
|
WO |
|
WO 91/11641 |
|
Aug 1991 |
|
WO |
|
WO 93/10015 |
|
May 1993 |
|
WO |
|
WO 96/03166 |
|
Feb 1996 |
|
WO |
|
WO 97/03712 |
|
Feb 1997 |
|
WO |
|
WO 97/47339 |
|
Dec 1997 |
|
WO |
|
Other References
PCT English language translation of International Preliminary
Report on Patentability for PCT/EP2005/006114; Jun. 7, 2005; 7p;
The International Bureau of WIPO; Geneva, Switzerland. cited by
other .
"Design for assembly";
http://web.archive.org/web20021026013912/http://www.scudc.scu.edu/cmdoc/d-
g.sub.--doc/develop/design/part/33000004.htm; Allegedly archived
Oct. 26, 2002; 10 pages. cited by other .
"Handbook of Plastics Joining: A Practical Guide"; William Andrew,
Inc.; 1997; pp. 121-124; Plastics Design Library; New York, USA.
cited by other .
Christians, Rolf, "Membranen in der Pneumatik," Fluid, pp. 39-46
(Apr. 1980). cited by other .
"Design for assembly"; http://web.archive.org/web/20021026013912/
http://www.scudc.scu.edu/cmdoc/dg.sub.--doc/develop/design/part/33000004.-
htm; Allegedly archived Oct. 26, 2002; 10 pages. cited by
other.
|
Primary Examiner: Yu; Justine
Assistant Examiner: Young; Rachel
Attorney, Agent or Firm: Brinks Hofer Gilson & Lione
Parent Case Text
CROSS-REFERENCE TO RELATED APPLICATION
This patent application is a continuation of International
Application PCT/EP2005/006114 published as PCT patent application
WO 2005/120618 A1, with an international filing date of Jun. 7,
2005 and entitled "DEVICE FOR CONNECTING A RESPIRATOR TO A
PATIENT," which claims the benefit of priority to German patent
application DE 102004027734 A1, filed Jun. 7, 2004 and entitled
"Vorrichtung zur Verbindung eines Beatmungsgerates mit dem
Patienten," the entire contents of each of which are incorporated
herein by reference.
Claims
What is claimed is:
1. An apparatus for connecting a respiratory device with a patient,
the apparatus comprising: a breathing tube having a proximal end
and a distal end configured to be inserted into a trachea of the
patient; an inflatable cuff positioned around a portion of the
breathing tube; a connection line having a proximal end and a
distal end connected to the cuff; a pressurized air reservoir
located adjacent to the proximal end of the connection line, the
pressurized air reservoir having an adjustable volume; and a valve
connected to the pressurized air reservoir and to the proximal end
of the connection line, the valve including: a first valve housing
portion defining a projection and an entry port associated with an
entry differential force chamber and configured to be coupled with
a syringe; a second valve housing portion defining a first exit
port associated with a first differential force chamber and
configured to be coupled with the proximal end of the connection
line; a second exit port associated with a second differential
force chamber and configured to be coupled with the pressurized air
reservoir; and a flexible membrane selectively sealingly separating
the first differential force chamber, the second differential force
chamber, and the entry differential force chamber from each other,
wherein the flexible membrane is configured to selectively connect
the first differential force chamber and the second differential
force chamber so as to maintain a substantially constant air
pressure in the cuff; wherein the flexible membrane defines a first
opening and the projection includes a first annular web configured
to pretension the flexible membrane towards the first exit port and
configured to surround the first opening in the flexible
membrane.
2. An apparatus as in claim 1, wherein the flexible membrane is a
three-way check valve.
3. An apparatus as in claim 2, wherein the flexible membrane is
configured to operate as a first check valve to regulate airflow
between the entry differential force chamber and the first
differential force chamber.
4. An apparatus as in claim 3, wherein the flexible membrane is
configured to operate as a second check valve to regulate airflow
between the entry differential force chamber and the second
differential force chamber.
5. An apparatus as in claim 4, wherein the flexible membrane is
configured to operate as a third check valve to regulate airflow
between the first differential force chamber and the second
differential force chamber.
6. An apparatus as in claim 1, further comprising a relief valve
selectively sealingly separating the first differential chamber and
a venting port.
7. An apparatus as in claim 6, wherein the relief valve is
configured to selectively connect the first differential chamber
and the venting port to deflate the cuff.
8. An apparatus as in claim 7, wherein the relief valve includes an
umbrella-type valve positioned over a channel extending between
first differential chamber and the venting port.
9. An apparatus as in claim 6, wherein the relief valve is
configured to permit the release of air from the cuff when an air
pressure within the cuff exceeds a desired level.
10. An apparatus as in claim 1, wherein the second valve housing
portion defines the second exit port.
11. An apparatus as in claim 10, wherein the flexible membrane is
clamped between the first valve housing portion and the second
valve housing portion.
12. An apparatus as in claim 10, the first annular web configured
to pretension the flexible membrane towards the first exit port and
configured to surround the first opening in the flexible membrane,
such that the entry differential force chamber is selectively
connected to the first differential force chamber via the first
opening in the flexible membrane.
13. An apparatus as in claim 12, wherein the first valve housing
portion defines a second annular web having a larger diameter than
the first annular web, the second annular web configured to
pretension the flexible membrane towards the first exit port; and
wherein the second valve housing portion defines a third annular
web having a diameter larger than that of the first annular web and
smaller than that of the second annular web, the third annular web
configured to pretension the flexible membrane towards the entry
port.
14. An apparatus as in claim 13, wherein the flexible membrane
defines a second opening positioned radially outwardly from the
second annular web such that the entry differential force chamber
is selectively connected to the second differential force chamber
via the second opening in the flexible membrane.
15. An apparatus as in claim 14, wherein the first valve housing
portion defines an annular space positioned radially outwardly from
the second annular web such that the entry differential force
chamber is selectively connected to the second differential force
chamber via the annular space and the second opening in the
flexible membrane.
16. An apparatus as in claim 10, wherein the pressurized air
reservoir includes a reservoir housing and pre-formed rubber
bellows positioned within the reservoir housing.
17. An apparatus as in claim 16, wherein the reservoir housing and
the second valve housing portion define a single, unitary
component.
18. An apparatus as in claim 10, wherein the flexible membrane
includes an annular protrusion at the circumference thereof,
wherein the first valve housing portion and the second valve
housing portion cooperate to define an annular recess, and wherein
the annular protrusion of the flexible membrane is received within
the annular recess.
19. An apparatus for connecting a respiratory device with a
patient, the apparatus comprising: a breathing tube having a
proximal end and a distal end configured to be inserted into a
trachea of the patient; an inflatable cuff positioned around a
portion of the breathing tube; a connection line having a proximal
end and a distal end connected to the cuff; a pressurized air
reservoir located adjacent to the proximal end of the connection
line, the pressurized air reservoir having an adjustable volume;
and a valve connected to the pressurized air reservoir and to the
proximal end of the connection line, the valve including: a first
valve housing portion defining a projection and an entry port
associated with an entry differential force chamber and configured
to be coupled with a syringe; a second valve housing portion
defining a first exit port associated with a first differential
force chamber and configured to be coupled with the proximal end of
the connection line; a second exit port associated with a second
differential force chamber and configured to be coupled with the
pressurized air reservoir; and a flexible membrane selectively
sealingly separating the first differential force chamber, the
second differential force chamber, and the entry differential force
chamber from each other, the flexible membrane configured to
operate as a three-way check valve; wherein the flexible membrane
defines a first opening and the projection includes a first annular
web configured to pretension the flexible membrane towards the
first exit port and configured to surround the first opening in the
flexible membrane.
20. An apparatus as in claim 19, wherein the flexible membrane is
configured to operate as a first check valve to regulate airflow
between the entry differential force chamber and the first
differential force chamber, wherein the flexible membrane is
configured to operate as a second check valve to regulate airflow
between the entry differential force chamber and the second
differential force chamber, and wherein the flexible membrane is
configured to operate as a third check valve to regulate airflow
between the first differential force chamber and the second
differential force chamber.
Description
FIELD OF THE INVENTION
This invention relates to an apparatus for connecting a respiratory
device with a patient.
BACKGROUND
This invention relates to an apparatus for connecting a respiratory
device with a patient having a breathing tube, such as an
endotracheal tube or tracheostomy tube. The breathing tube is
insertable into the patient's trachea and is connected to a source
of breathing gas, such as air or oxygen. An inflatable cuff
surrounds a portion of the breathing tube adjacent to the distal
end of the breathing tube. When inflated, the cuff forms a seal
with the inner walls of the patient's trachea, thereby preventing
the breathing gas from escaping through the patient's mouth.
Specifically, the inflatable cuff is connected to a connection line
which provides an inflation gas, such as air or oxygen. When
inflated, the cuff forms a generally air-tight seal with the
patient's trachea so the breathing gas delivered from the breathing
tube is forced to flow towards the patient's lungs rather than back
up his/her trachea. It is desirable to control the air pressure
within the cuff in order to maintain a seal between the cuff and
the patient's trachea and in order to minimize or reduce the risk
of over-inflating the cuff and causing trauma to the patient's
trachea.
One currently-known apparatus for regulating the pressure in the
cuff is disclosed in U.S. Pat. No. 3,794,043 (the '043 patent). The
'043 patent discloses an apparatus used for the artificial
respiration of patients. After the breathing tube has been inserted
into the trachea of the patient, a syringe is connected to a valve
for inflating the cuff to a pressure between 16 and 25 millimeters
of Mercury. Simultaneously with the inflation of the cuff, a
pressurized air reservoir connected to the valve is also filled.
After removal of the syringe, the valve maintains a constant
pressure in the cuff by pressure differentiation between the cuff
and the air reservoir. This arrangement is such that the air from
the pressurized air reservoir can flow back to the cuff
comparatively easily while the air in the opposite direction, i.e.
from the cuff to the pressurized air reservoir, should be with a
reduced flow rate to prevent leaks from occurring between the cuff
and the trachea.
Although this design performs in a satisfactory manner, it is
relatively complex and expensive to produce, and it requires
relatively sensitive materials. For example, the valve in this
design includes two housings positioned within each other, where
the inner housing receives a mushroom-shaped body serving as a
valve member, with bottom end thereof forming the sealing surface
of the check valve that controls entry of air into the valve. A
separate push rod, which is made of plastic, is provided for
actuating the check valve. During the filling of the cuff, by means
of the syringe, the check valve has to be displaced to open the
valve. This design includes a relatively high number of parts and
is relatively complex, both of which may be disadvantageous.
Additionally, the mushroom-shaped body serving as the valve member
is made of a natural rubber. Specifically, the rubber balloon is
clamped and fixed at the valve body between the two housings
positioned within each other and the head of the mushroom shaped
valve body is positioned within the balloon of natural rubber in
combination with its margin engaging the top side of the valve and
relief openings within the head the part is acting as a control
valve. It is undesirable to use natural rubber because it may be
subject to premature wear.
It is therefore desirable to provide an apparatus for connecting a
respiratory device with a patient having reduced part complexity
and reduced manufacturing costs, as well as improved durability and
potentially reduced part wear.
BRIEF SUMMARY
This invention seeks to address the above-mentioned shortcomings of
the prior art. An apparatus for connecting a respiratory device
with a patient is provided, including a breathing tube for
insertion into a patient's trachea, an inflatable cuff surrounding
around a distal portion of the breathing tube, a connection
connected to the cuff for providing inflating air flow thereto, a
pressurized air reservoir having an adjustable volume, and a valve
connected to the pressurized air reservoir and to the proximal end
of the connection line. The valve includes an entry port associated
with an entry differential force chamber and configured to be
coupled with a syringe, a first exit port associated with a first
differential force chamber and configured to be coupled with the
proximal end of the connection line, a second exit port associated
with a second differential force chamber and configured to be
coupled with the pressurized air reservoir, and a flexible membrane
selectively sealingly separating the first differential force
chamber, the second differential force chamber, and the entry
differential force chamber from each other. The flexible membrane
is configured to selectively connect the first differential force
chamber and the second differential force chamber so as to maintain
a substantially constant air pressure in the cuff.
In one aspect, the flexible membrane is a three-way check valve.
The flexible membrane operates as a first check valve to regulate
airflow between the entry differential force chamber and the first
differential force chamber. The flexible membrane also operates as
a second check valve to regulate airflow between the entry
differential force chamber and the second differential force
chamber. The flexible membrane may also operate as a third check
valve to regulate airflow between the first differential force
chamber and the second differential force chamber.
In another aspect, a relief valve is provided to selectively
sealingly separate the first differential chamber and a venting
port. The relief valve selectively connects the first differential
chamber and the venting port in order to deflate the cuff before
removal of the respiratory device. The relief valve includes an
umbrella-type valve positioned over a channel extending between
first differential chamber and the venting port.
In yet another aspect, the valve includes a first valve housing
portion defining the entry port and a second valve housing portion
defining the first exit port, the second exit port, and the venting
port. The flexible membrane may be clamped between the first valve
housing portion and the second valve housing portion.
In another aspect, the first valve housing portion defines a
projection and the flexible membrane defines a first opening, and
the projection includes a first annular web pretensioning the
flexible membrane towards the first exit port and surrounding the
first opening in the flexible membrane. Thus, the entry
differential force chamber is selectively connected to the first
differential force chamber via the first opening in the flexible
membrane. The first valve housing portion also defines a second
annular web having a larger diameter than the first annular web,
and the second annular web pretensions the flexible membrane
towards the first exit port. Additionally, the second valve housing
portion defines a third annular web having a diameter larger than
that of the first annular web and smaller than that of the second
annular web. The third annular web pretensions the flexible
membrane towards the entry port. Furthermore, the flexible membrane
defines a second opening positioned radially outwardly from the
second annular web such that the entry differential force chamber
is selectively connected to the second differential force chamber
via the second opening in the flexible membrane.
In yet another aspect, the pressurized air reservoir includes a
reservoir housing and pre-formed rubber bellows positioned within
the reservoir housing. The reservoir housing and the second valve
housing portion may define a single, unitary component.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partial-section, schematic view of an embodiment;
FIG. 2 an exterior view of the apparatus shown in FIG. 1 in the
direction of the arrow generally indicated by II;
FIG. 3 a cross-sectional view of the valve taken along the line
III-III in FIG. 2; and
FIG. 4 an enlarged view of a portion of the valve shown FIG. 3.
DETAILED DESCRIPTION OF THE DRAWINGS AND THE PRESENTLY PREFERRED
EMBODIMENTS
Referring now to preferred embodiments, FIG. 1 shows one
embodiment, generally designated by 1, for connecting a respiratory
device (not shown) with a patient's trachea 2. The apparatus 1
includes a flexible breathing tube 4 insertable into the patient's
trachea 2 and connectable with a source of breathing gas, such as
air or oxygen. Specifically, the proximal end 12 of the breathing
tube 4 is connected to a respiratory device. The breathing tube 4
supplies breathing gas to the patient's lungs in regular intervals.
The breathing tube 4 is preferably an endotracheal tube or a
tracheostomy tube.
An inflatable cuff 8 surrounds a portion of the breathing tube 4
adjacent to the distal end 6 of the breathing tube 4. The cuff 8
includes an air chamber surrounding the breathing tube 4. In its
collapsed state, the cuff 8 is collapsed against the breathing tube
4 such that the cuff and the breathing tube 4 are able to be
inserted into the trachea. To this end, the surgeon selects a
diameter of the breathing tube 4 based on the diameter of the
trachea. In order to inflate the cuff 8 for forming a seal with the
wall of the trachea 2, the distal end of a relatively small
connection line 10 is connected with the inside of the cuff 8.
Additionally, the proximal end 18 of the connection line 10 is
connected to an elastic pressurized air reservoir 14 via a valve
16, as will be discussed further below.
The valve 16 is preferably at least a three-way-valve and it is
positioned between the proximal end 18 of the connection line 10
and the pressurized air reservoir 14. The valve 16 includes an
entry port 20, a first exit 24, and a second exit 26. Pressurized
air can be introduced to the cuff 8 via the entry port 20. For
example, a suitable device, such as a syringe, may be inserted into
a connector 64 to deliver air to the cuff 8 via an entry port 20 of
the valve. The first exit 24 is connected to the connection line 10
and the second exit 26 is connected to the pressurized air
reservoir 14.
According to one embodiment of the invention, the valve 16 operates
as a three-way check valve and as a differential pressure valve 16,
as will be discussed in more detail below. At the entry port 20,
the valve 16 operates as a first check valve that closes
automatically when the syringe is removed to prevent air from
exiting the cuff 8.
As will also be discussed further below, the valve 16 is able to
selectively connect the cuff 8 and the pressurized air reservoir 14
to maintain a generally constant pressure within the cuff 8.
As best shown in FIG. 4, the valve 16 includes the first exit 24
associated with a first differential force chamber 28; a second
exit 26 associated with a second force chamber 30; and an entry
port 20 associated with a third differential force chamber 32. The
differential force chambers 28, 30 and 32 are selectively sealingly
separated from each other by a membrane disk 6.
Additionally, the first differential force chamber 28 of the first
exit 24 are connected with a relief valve 36 having an exit 38 by
the means of which the relief valve 36 for the decompression of the
cuff 8 can be activated by means of vacuum which is more fully
described further below.
The housing of the differential pressure valve 16 includes two
valve housing halves 40 and 42 sealingly connected with each other.
The first valve housing half 40 defines the entry port 20 and the
second housing half 42 defines two exits 24 and 26 as well as the
relief valve 36. The membrane disk 34 is clamped between the first
and the second valve housing half 40 and 42. Each of the housing
halves is preferably a single, unitary component produced by
injection molding of a plastic material.
A pin-like projection 44 is defined by the first valve housing half
40 and is positioned within the first differential force chamber
28. A first annular web 48 is formed on the top end of the
projection 44. The projection 44 and the annular web 48 pretension
the membrane disk 34 in the direction of the first exit 24, and the
annular web 48 surrounds an opening 50 provided in the membrane
disk 34.
Connection channels 52 are provided in the first valve housing half
40, radially exterior of the projection 44. The connection channels
52 connect the entry port 20 and the entry differential force
chamber 32. The entry differential force chamber 32 further is
limited at the circumference thereof by a second annular web 53
which is preferably unitarily formed with the first housing half 40
and which has a larger diameter than the first annular web 48. The
second annular web 53 also pretensions the membrane disk 34 in the
direction of the first exit.
The entry differential force chamber 32 therefore is defined by the
annular space between the first annular web 48 and the second
annular web 53 and by the parts of the membrane disk 34 contacting
the webs 48, 53. The entry differential force chamber 32 defines
the entry chamber for air when filling the cuff 8 and the
pressurized air reservoir 14, and the membrane disk 34 operates as:
a first check valve between the entry differential force chamber 32
and the first differential force chamber 28; a second check valve
between the entry differential force chamber 32 and the second
differential force chamber 30; and a third check valve between the
first differential force chamber 28 and the second differential
force chamber 30.
As best shown in FIGS. 3 and 4, the first exit 24 is positioned
parallel and generally coaxial to the entry port 20 when the two
valve housing halves 40 and 42 are connected with each other.
In the first housing half 40, an annular space 54 is formed
radially exterior of the second annular web 53. The annular space
is connected to the second differential force chamber 30 by
openings 56 in the membrane disk 34.
In the second valve housing half 42, the first exit 24 is
associated with the first differential force chamber 28. Also, a
third annular web 58 is provided which surrounds the first exit 24.
The third annular web 58 pretensions the membrane disk 34 in the
direction of the entry port 20 (against the pretension created by
the annular webs 48 and 53). The diameter of the third annular web
58 is larger than the diameter of the first annular web 48 and
smaller than the diameter of the second annular web 53. Therefore,
the first differential force chamber 28 is defined by the space
delimited by the third annular web 58 and the corresponding parts
of the membrane disk as well as by the space within the first
annular web 48 connected by the openings 50.
As best shown in FIG. 4, the relief valve 36 can be opened to the
ambient air, thereby connecting the first differential force
chamber 28 to the ambient air. A connector 62 is connected with the
second housing half 42 and a syringe can be inserted into the
connector 62 for drawing air out of the first differential force
chamber 28. Specifically, the relief valve 36 is positioned in the
housing 60 and is preferably an umbrella-type valve 84 for
facilitating deflation of the cuff 8 and the rubber bellows 66. The
elastic membrane 86 forming the umbrella head covers one or more
connecting channels 88 between the interior of the housing 60 and
the first differential force chamber 28. When a syringe is inserted
into the connector 62 of the housing 60 in an air-tight manner and
the plunger is drawn back, then the vacuum created in the interior
of the housing 60 lifts the elastic membrane 86 such that the
connecting channels 88 are opened and that the vacuum created
thereby in the first differential force chamber 28 and the second
differential force chamber 30 lifts the membrane disk 34 from the
annular web 58 such as to remove the air contained in the cuff 8
and the air contained in the rubber bellows 66. The relief valve 36
also serves as a safety valve for preventing or minimizing
overpressurization of the cuff 8. Specifically, the relief valve 36
may be configured to permit the release of air if the pressure
within the cuff 8 reaches a certain level.
As further shown in the drawings, the pressurized air reservoir 14
may be formed as a rubber bellows 66 connected with the second exit
26 which is positioned in a housing 68. As best shown in FIG. 4,
the bottom 70 of the housing 68 and the second housing half 42
define a single, unitary component. A connecting channel 72 leading
to the second exit 26 is provided with a suitable coupling member
74 in the bottom 70 of the housing which is surrounding the second
exit 26 and which in a form-fit manner is connected with the rubber
bellows. To achieve a compact construction, the exit opening 76 of
the second differential force chamber 30 extends in an angle with
respect to the connection channel 72.
In the exemplary embodiment, the membrane disk 34 at a
circumference thereof is formed with a unitary annular protrusion
78 which is received in oppositely positioned annular recesses 80
and 82 in the valve housing halves 40 and 42 when the valve housing
halves 40 and 42 are connected with each other.
During operation of the apparatus, the breathing tube 4 is inserted
into the trachea 2 of the patient. Once the cuff 8 is positioned
within the trachea 2 as desired, the cuff 8 and the pressurized air
reservoir 14 are inflated as desired. Specifically, a syringe or
other appropriate device is connected to the entry port 20 and an
inflating gas such as air or oxygen is delivered to the entry
differential force chamber 32 via the connection channels 52. For
example, approximately 40 to 50 milliliters of air is introduced to
the entry port 20 such that the membrane disk 34 is lifted upward
from the first annular web 48, which allows air to flow through the
opening 50, into the first differential force chamber 28, and into
the cuff 8. Simultaneously, the membrane disk 34 also lifts upward
from the second annular web 53, which allows air to flow through
the openings 56, into the second differential force chamber 30, and
into the pressurized air reservoir 14.
After the injection of airflow from the syringe, the membrane disk
34 reengages the first and second annular webs 48, 53, thereby
operating as the first and second check valve, respectively.
Specifically, the air in the cuff 8 and the pressurized air
reservoir 14 is prevented from exiting the entry port 20 due to
respective seals between the membrane disk 34 and the first and
second annular webs 48, 53.
In this state, the cuff 8 maintains a generally constant pressure,
such that the respective components 8, 66 have the same air
pressure. For example, if the air pressure in the cuff 8 changes,
such as if the patient moves applies pressure to the cuff 8 or if
excess respiration air acts on the outer surface of the cuff 8, air
is able to flow from the cuff 8 to the rubber bellows 66. The
membrane disk 34 and the third annular web 58 cooperate to define
the third check valve and a differential pressure valve.
Specifically, an unbalanced air pressure between the cuff 8 and the
rubber bellows 66 causes the membrane disk 34 to deflect downward
off of the third annular web 58, thereby temporarily connecting the
first and second differential force chambers 28, 30. The rubber
bellows 66 in this design serves as a pressurized air reservoir
14.
Conversely, when the pressure in the cuff 8 decreases, such as due
to respiration or movement of the patient, the pressure in the
first exit 24 is smaller than the pressure in the second exit 26
such that this pressure acting in the second differential force
chamber again can lift the membrane disk 34 from the third annular
web 58 and the air can flow back into the cuff 8 through the exit
24 and the connecting line 10, wherein in this direction the flow
is meeting a substantially smaller resistance compared with a flow
from the cuff 8 since the available area of the membrane disk 24 in
the second differential force chamber is substantially larger.
In the above-described embodiment, the cuff 8 is able to maintain a
generally constant seal with the trachea, despite varying factors
such as movement of the patient or changes in pressure in the
patient's trachea.
It is therefore intended that the foregoing detailed description be
regarded as illustrative rather than limiting, and that it be
understood that it is the following claims, including all
equivalents, are intended to define the spirit and scope of this
invention. More particularly, the apparatus and assembly described
are merely an exemplary apparatus and assembly, and they are not
intended to be limiting. Many of the steps and devices for
performing the steps described above may be eliminated or replaced
by alternative steps and devices.
* * * * *
References