U.S. patent number 3,731,691 [Application Number 05/075,163] was granted by the patent office on 1973-05-08 for endotracheal tube and connector unit.
This patent grant is currently assigned to Lorton Laboratories, Ltd.. Invention is credited to Allen Chen.
United States Patent |
3,731,691 |
Chen |
May 8, 1973 |
ENDOTRACHEAL TUBE AND CONNECTOR UNIT
Abstract
A device for the endotracheal administration of a gaseous
anesthetic has a flexible tube for insertion into the trachea,
including an inflation cuff integrally joined with and surrounding
the tube adjacent the distal portion thereof, and an inflation duct
formed in the tube and isolated from the interior thereof, which
duct extends from the cuff to proximal portions of the tube and
through which inflation air may be supplied to the cuff. The
proximal portions of the tube are integrally joined with a rigid
connector having a valve member in air communication with the
inflation duct for controlling the supply of inflation air to the
cuff.
Inventors: |
Chen; Allen (Belleville,
MI) |
Assignee: |
Lorton Laboratories, Ltd. (New
York, NY)
|
Family
ID: |
22123977 |
Appl.
No.: |
05/075,163 |
Filed: |
September 24, 1970 |
Current U.S.
Class: |
128/207.15;
604/100.01 |
Current CPC
Class: |
A61M
16/044 (20130101); A61M 16/0463 (20130101); A61M
2205/32 (20130101) |
Current International
Class: |
A61M
16/04 (20060101); A61m 025/00 () |
Field of
Search: |
;128/349B,349BV,351
;22/27,89A |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Other References
Brochure of The Shiley Disposable Tracheostomy Tube, copyright
September, 1970..
|
Primary Examiner: Medbery; Aldrich F.
Claims
What is claimed is:
1. A device for the endotracheal administration of a gaseous
anesthetic comprising, a flexible tube for insertion into the
trachea, connector means operably connected at one end to the
proximal portion of said tube and adapted to be connected at its
other end to a source of anesthetic, an inflatable cuff formed of a
flexible material integrally joined with and surrounding the
periphery of said tube adjacent the distal portion thereof, said
tube having an inflation duct isolated from the interior thereof
and extending from said connector means to said cuff for supplying
inflation air to said cuff, a valve assembly in said connector
means in air communication with said inflation duct for controlling
the supply of inflation air to said cuff, said valve assembly
including first and second air chambers in fluid communication with
each other, said first air chamber being adapted to receive an
instrument inserted therein for supplying inflation air to said
valve assembly, said second air chamber being in fluid
communication with said duct and providing a valve seat in said
valve assembly downstream of said first air chamber, a valve
closure element adapted to engage said valve seat to prevent air
flow downstream thereof, and resilient means operably engaged with
said closure element for urging said element against said valve
seat;
said connector means including a wall portion having an opening
therein providing communication between said valve assembly and the
atmosphere; and,
inflatable pressure indicator means formed of a manually frangible
flexible material comprising a diaphragm secured to said connector
means and closing said wall opening, said indicator means being
formed of a flexible material stiffer than the material forming
said cuff whereby upon the supply of air to said cuff through said
valve assembly, said cuff expands prior to inflation of said
indicator means, until further inflation of said cuff is prevented
by engagement of said cuff with the walls of the trachea, whereupon
continued supply of air to said cuff increases the pressure therein
causing inflation of said indicator means, which thereby provides
an indication that said cuff is fully inflated, said diaphragm
having an operator engageable tab for tearing of said diaphragm to
exhaust air from said cuff upon completion of the endotracheal
procedure.
2. A device as in claim 1 wherein said connector has a toileting
opening therein in generally axial alignment with said tube and
means for selectively opening and closing said toileting
opening.
3. A device as in claim 1 wherein said flexible tube and connector
means are separate elements integrally joined.
4. A device as in claim 3 wherein said connector means has an
axially tapered distal portion, and said proximal tube portion
axially receives said tapered connector portion to form an integral
connection therewith.
5. A device as in claim 4 wherein said distal portion of said
connector means has an annular peripheral groove in communication
with said valve assembly and forms a portion of the flow path of
said inflation air, said tube having a generally transversely
extending bore therein adjacent the proximal portion thereof
providing communication between said inflation duct and said groove
when said distal connector portion is received in said proximal
tube portion.
6. A device as in claim 1 wherein said closure element comprises a
ball and said resilient member comprises a spring element operably
engaged between said ball and a wall portion of said connector
means to urge said ball against said valve seat.
7. A device as in claim 1 wherein said resilient means comprises a
resilient wall member forming a portion of said connector means,
and said device further includes a control member operably
connected to said resilient wall portion and to said closure
element whereby said closure element is urged against said valve
seat by said wall portion.
8. A device as in claim 7 wherein said control member extends
through said resilient wall portion and is adapted to be moved
outwardly thereof to move said closure element away from said valve
seat for venting said cuff.
9. A device as in claim 1 wherein said connector means is provided
with a wall separating said first and second air chambers and
having an aperture therein providing air communication between said
chambers, and wherein said valve assembly includes a tubular body
slidably received in said first chamber, a valve control member
connected to said body at one end thereof and extending through
said aperture, said valve closure element being fixed to the other
end of said control member within said second air chamber and being
adapted to close said aperture to prevent air flow between said
chambers, and said resilient means comprising a compression spring
in said first chamber operably engaged between said body and said
chamber separating wall for urging said closure element into
engagement with said wall in said second air chamber to close said
aperture.
10. A device as in claim 9 wherein said first connector chamber has
a longitudinal groove formed therein and said body has a transverse
bore therein adapted to communicate with said groove, whereby said
groove and said bore provide an intake path for inflation air to a
syringe inserted in said body in a first position thereof, said
bore being moved out of communication with said groove in a second
position of said body wherein said syringe and said body are moved
towards said wall to open said aperture for introduction of
inflation air to said cuff.
11. A device as in claim 1 wherein said valve assembly includes a
tubular member rotatably mounted in said connector means and having
a transverse bore therein, said connector means having a
longitudinal groove therein communicating at one end with said
transverse bore and at its opposed end with the atmosphere, whereby
a syringe inserted in said first valve air chamber is adapted to
receive ambient air for inflating said cuff.
12. A device as in claim 11 wherein said tubular member and said
connector means include cooperating detent members for maintaining
said tubular member in a plurality of angular positions within said
connector means, whereby in one of said positions said groove and
said transverse bore are in air communication and in the remainder
of said positions said groove and said transverse bore are out of
communication to prevent air flow into and out of said connector
means.
13. A device as in claim 12 wherein said tubular member has a
longitudinal groove on the periphery thereof adapted to be
positioned in air communication with said groove in said connector
means for venting said collar when said tubular member is in
another of said angular positions.
14. A device as in claim 1 wherein said connector means has an
axially tapered anterior portion including an annular shouldered
recess axially receiving said posterior tube portion.
15. A device as in claim 14 wherein said tube has an annular groove
on the periphery of its posterior portion, said groove
communicating with said inflation duct and said valve assembly to
provide air communication therebetween.
16. A device as in claim 1 wherein said closure element includes a
main body portion adapted to engage said valve seat and a stem
portion extending through said second air chamber into said first
air chamber, said stem being positioned for operative engagement
with said instrument, whereby movement of said instrument into said
first air chamber moves said main body portion away from said valve
seat.
Description
The present invention relates to devices for the endotracheal
administration of a gaseous anesthetic.
At present, the endotracheal administration of gaseous anesthetics
during surgery is accomplished through a simple flexible tube, such
as of rubber or plastic, of a length and diameter suitable to the
size and length of the trachea of the patient being anesthesized.
Certain of such tubes have been provided with an inflatable cuff
adjacent the distal portions thereof, which cuff, when filled with
air, is inflated to a bulbous shape for retaining the tube in
position after the tube has been inserted into the trachea. This
collar or cuff is generally inflated through an inflation tube
which is connected at one end to the cuff and extends to a position
adjacent the proximal of the tube where it terminates in a
laterally extending inflation arm provided with a plug to seal the
mouth thereof. In some cases the plug is simply a removable closure
member, although it has been proposed that the plug be an integral
part of the inflation arm through which a hypodermic needle may be
inserted for supplying inflation air to the cuff.
The arrangements of the previously proposed endotracheal tubes
which utilize an inflation cuff are subject to several serious
objections. Typically, the inflation tube is a separate element
independent of the endotracheal tube and thus adds substantially to
the mass which must be inserted in the trachea. The added mass
tends to interfere with surgical procedures that sometimes are
required in the trachea during operations. Further problems arise
with regard to the closure mechanism used for the inflation tube.
Where a closure plug is utilized, leaks often occur thereabout, so
that the cuff deflates and loses its capacity to maintain the tube
in proper position within the organ. The addition, it is difficult
to prevent loss of air during filling since the syringe used to
supply the air must be removed from the mouth of the inflation duct
for insertion of the closure member. To prevent loss of air during
this period the physician generally clamps the inflation tube until
the plug is properly inserted. This requires an additional time
consuming step and an additional surgical implement. Finally, in
the event that the cuff is overinflated the physician cannot
accurately or conveniently control release of air with the plug
closure member.
Where a resealing or plug valve adapted to be pierced by the needle
of a syringe is used, the needle often inadvertently pierces the
wall of the inflation arm, thereby rendering the tube useless and
perhaps injuring the physician. Further, when it is desired to
remove the tube from the body of the patient, evacuation of the
cuff by means of the hypodermic syringe is a difficult and time
consuming operation.
These numerous disadvantages of the prior art are overcome by the
devices of the present invention comprising a flexible tube adapted
to be inserted into the trachea, and integrally joined with a more
rigid connector means for connecting the device to a source of
gaseous anesthetic. The tube is provided with a cuff and inflation
duct which extends along the tube to a valve member integrally
joined with the connector means. The valve means is adapted to
control air flow into and out of the cuff and is conveniently
operated by the physician for inflating and deflating the cuff.
A better understanding of the present invention and its many
advantages will be had by referring to the accompanying drawings in
which:
FIG. 1 is a perspective view of an endotracheal tube constructed in
accordance with the present invention, including an inflation cuff
and a valve control means therefor;
FIG. 2 is a side view, in section, of portions of the endotracheal
tube illustrated in FIG. 1;
FIG. 3 is a sectional view taken on line 3--3 of FIG. 1
illustrating one embodiment of the valve control means;
FIG. 4 - 8 are partial sectional views, similar to FIG. 3, of other
embodiments of the valve control means;
FIG. 9 is a partial sectional view, similar to FIG. 2, showing
still another embodiment of the valve control means;
FIG. 10 is a sectional view taken on line 10--10 of FIG. 9;
FIG. 11 is a partial side view of a connector member for use in the
present invention including yet another embodiment of the valve
control means;
FIG. 12 is a sectional view taken on staggered section line 12--12
of FIG. 11;
FIG. 13 is a sectional view similar to FIG. 12 showing the valve
control mechanism in another position thereof;
FIG. 14 is a sectional view taken on line 14--14 of FIG. 14;
FIG. 15 is a sectional view taken on line 15--15 of FIG. 12;
FIG. 16 is a partial sectional view, similar to FIG. 2, of another
embodiment of the present invention; and
FIG. 17 is a sectional view taken on line 17--17 of FIG. 16.
Referring to the drawing in detail, and initially to FIG. 1
thereof, it will be seen that endotracheal tube 30 embodying the
present invention comprises flexible tube 32, whose proximal end
portion 34 receives and is connected to the distal portion 35 of
connector member 36. Connector 36 is formed with opening 15 through
which access is granted to proximal portions of tube 32 for
endotracheal toileting. Closure member 16 for opening 15 is secured
to connector member 36 by flexible attaching means 17 to prevent
inadvertent loss of member 16. Connector 36 also has fitting 14
formed integrally therewith for connection to a source of
anesthetic.
Tube 32 is provided with inflation cuff 38 at its distal portion
40, which cuff surrounds the periphery of the tube and defines
chamber 42 therebetween, as seen in FIG. 2. Cuff 38 is made of a
relatively thin flexible material such as rubber or plastic. After
tube 32 is inserted in the trachea, inflation air is supplied to
chamber 42, as more fully described hereinafter, to inflate the
cuff in order to retain the tube in the desired position within the
trachea. To supply inflation air to cuff 38 and chamber 42,
inflation duct 44 of relatively small diameter is formed in the
wall of tube 32. As seen in FIG. 2, duct 44 is isolated from the
interior portion of tube 32 through which anesthetic is supplied to
the patient. Proximal portion 45 of duct 44 is provided with
generally laterally extending duct 46 through which inflation fluid
is supplied to chamber 42. Forward end 48 of duct 44 may be closed
in any convenient manner, as for example, by plug 49 to prevent
loss of inflation air through end 48. Preferably plug 49 is formed
of a metal such as stainless steel so that when the tube is
inserted in the trachea the plug will be visible on X rays of
fluoroscope equipment to enable the physician to accurately
determine its location.
It is noted that in the illustrative embodiment of the invention
shown in FIG. 2, duct 44 is formed as a bore directly in the wall
of tube 32 thereby providing a relatively streamlined tube
construction. However, it is contemplated that duct 44 may be
provided by means of a separate tube integrally joined to the
periphery of tube 32, as for example by seating such tube in a
groove formed in the exterior surface of tube 32.
Valve member 50, provided on connector 36, is integral therewith,
and is in fluid communication with the proximal portion of duct 44,
as more fully described hereinafter, in order to control the supply
of air to cuff 38. Additionally, valve 50 provides a convenient
mechanism for venting the collar on completion of administration of
the anesthetic. Member 50 regulates air flow from a source thereof
through supply duct 60 formed in connector 36, which duct provides
fluid communication between valve member 50 and fluid distribution
channel 52 also formed in connector 36. Channel 52 is an annular
groove formed in tapered shoulder 54, which latter receives the
proximal portion 34 of tube 32 and forms an airtight connection
therewith.
Proximal portion 56 of tube 44 is provided with a generally
laterally extending duct 58 through which air flows to duct 44 from
channel 52. In this manner, a readily assembled device is provided
since connector 36 may be inserted within tube 32 in any angular
position without aligning fluid supply conduits 58 and 60.
Accordingly, ducts 58 and 60 may be, for example, at positions
180.degree. apart with respect to each other and yet inflation air
is readily supplied to duct 44. Extreme proximal end portion 62 of
tube 42 may be closed by plug member 64 in a manner similar to that
of distal portion 48 or by any other convenient mechanism.
As mentioned, control valve 50 is in fluid communication with duct
60 and regulates the supply of inflation air therethrough. The
valve is conveniently located on connector means 36 to facilitate
control of air flow by the physician during the administration of
anesthesia. Each of the embodiments of the control valve
illustrated in FIGS. 7 through 17 is constructed for use with a
conventional syringe which allows the physician to control the
amount of air ultimately supplied to cuff 38.
Referring now to FIG. 3 of the drawings, one embodiment of control
valve 50 is illustrated during operation in conjunction with
syringe 66 (shown in phantom) through which inflation air is
supplied to valve 50 and cuff 38. Valve mechanism 50 is located in
chamber 68 formed in connector 36, in communication with supply
duct 60, and includes valve structure 70 having first bore 72 in
which nose 74 of syringe 66 is inserted. Valve structure 70 has
second bore 76 axially aligned with first bore 72 and provides
valve seat 78 at the end of bore 72 opening towards the interior of
chamber 68. Ball valve or closure element 80 is urged into
engagement with valve seat 78 by spring 82 which is maintained in
position between closure element 80 and wall 84 of connector 36 by
nipple 86 which extends into the interior of the coiled spring. As
inflation air is supplied from syringe 66 to bore 72, the pressure
developed therein moves ball 80 away from seat 78 so that inflation
air is supplied to the interior of chamber 68. Inflation air thence
flows from chamber 68 through duct 60 to cuff 38 in the manner
described above. In the event that the first syringe full of air is
inadequate to inflate cuff 38, the physician may conveniently
remove nose 74 from valve 50 to refill the syringe without loss of
air from cuff 38 since valve member 80 automatically returns to
engagement with seat 78 to prevent air leakage. After the syringe
is again filled the inflation process is merely repeated as
described above.
Connector 36 is also provided with flexible diaphragm 88 forming
one side of chamber 68. Diaphragm 88 is adapted to serve as an
indicator to enable the physician to determine whether the cuff has
been inflated to the required extent. Since cuff 38 is within the
trachea when the device is in use, the physician is unable to
visually inspect the cuff. Thus, exterior indicator 88 is provided
to assist him in determining whether the cuff has been adequately
inflated or if it leaks during use. Diaphragm 88 is made of a
somewhat stiffer material than cuff 38, so that during the
inflation process cuff 38 expands first. When cuff 38 is inflated
to a point wherein the cuff is urged against the walls of the
trachea, the resistance to further inflation, caused by the
trachea, will increase pressure within the system. The increased
pressure causes diaphragm 88 to move outwardly towards the dotted
line position illustrated in FIG. 3 to provide the physician with
an indication that cuff 38 is inflated. Since chamber 42 and
chamber 68 are in free air communication through the ducts 42 and
60, in the event that the diaphragm does not move to the dotted
line position the doctor will know that the cuff has not been
satisfactorily inflated and may then discontinue use of that
endotracheal tube and replace it with one operating satisfactorily.
In the event that diaphragm 88 expands too far, indicating an
undesirable over-inflation of cuff 38 which would injure the
contacted surfaces or mucosa of the trachea, the physician may
conveniently vent the collar by merely inserting a needle or other
narrow instrument through bore 76 to urge ball 80 away from seat
78, thereby permitting escape of the excess air in a convenient and
accurately controlled manner.
Upon completion of administration of the anesthetic, and when it
becomes desirable to remove the endotracheal tube, cuff 38 must be
deflated so that the tube may be withdrawn without injuring the
patient. In the valve mechanism illustrated in FIG. 3, cuff 38 may
be conveniently deflated by breaking diaphragm 88 so that chambers
68 and 42 are vented. To facilitate breaking of diaphragm 88, an
extension tab 89 is provided which may be grasped by the physician
for tearing the diaphragm. Since the endotracheal tubes of the
present invention are intended to be disposable, this structure
makes venting the collar simple and convenient with little
additional expense.
Another valve construction provided for use in the present
invention is illustrated in FIG. 4 and includes closure member 90
which is adapted to engage valve seat 78 to control flow of
inflation air through duct 78 into chamber 68. Closure element 90
has stem portion 92 integrally formed with mounting portion 94
sealed in aperture 96 in side wall 84 of connector 36. Stem 92 is
flexibly connected to and integrally formed with mounting portion
94 by generally conically shaped disc 98 connected at its apex 99
to stem 92. Disc 98 urges the stem and closure member 90 towards
valve seat 78.
Stem 92 extends beyond the surface of connector 36 so that its free
end 100 may be conveniently grasped by the physician to control the
position of closure member 90. In this manner, when it is desired
to vent cuff 38 to remove excess air, or on completion of the
surgical procedure, the physician may merely move stem 92 away from
valve seat 78 so that closure member 90 occupies the dotted line
position in FIG. 8. The inflation air is then vented through duct
60 and bore 76 to the atmosphere. In this embodiment, connector 38
is also provided with indicator diaphragm 88, but no tab is
provided since valve control member or stem 92 provides for the
venting function.
FIG. 5 illustrates yet another valve embodiment adapted for use in
the present invention, and which is similar in construction to the
valve structure shown in FIG. 3. The valve of FIG. 5 includes ball
valve element 80 adapted to engage valve seat 78 to control the
supply of inflation air through bores 72 and 76. In this case,
however, spring 82 is held in compression between wall 102 formed
in cavity 68 and is seated on nipple 104 formed integrally with
wall 102 to maintain the position of the spring with respect to
ball 80.
Wall 102 is formed with bore 106 which communicates between chamber
68 and second chamber 108. The latter is provided with flexible
diaphragm 110, similar in construction to diaphragm 88, which
serves as an inflation indicator for cuff 38. Thus, as inflation
air is supplied through bores 72 and 76 from a syringe (not shown),
ball 80 is moved away from valve seat 78 and the air thus supplied
passes through duct 60 to cuff 38. Cuff 38 and chamber 108 are in
air communication through duct 106, so that when cuff 38 is
inflated and engaged with the walls of the trachea, the pressure in
chambers 42 and 108 will increase sequentially, as described above,
until diaphragm 110 expands and moves to its dotted line position.
To vent cuff 38 in this embodiment, tab 112 is provided, similar in
construction to tab 89, so that the diaphragm may be ruptured and
inflation air vented through duct 106 from cuff 38 on completion of
the anesthetic procedures.
Yet another valve structure suitable for use in the present
invention is illustrated in FIG. 6 showing connector 36 provided
with a pair of annular chambers 116 and 118 separated by annular
wall 120. Wall 120 has aperture 122 therein formed by tapered edge
123 which provides valve seat 124. Resilient closure member 126,
preferably of a material such as rubber, is constrained within
chamber 118 between wall 128 of connector 36 and valve seat 124.
Control element 130 is slidably mounted within chamber 116 and has
nipple 132 formed integrally therewith which extends through bore
122 and engages closure member 126. Connector 36 adjacent chamber
116 has an extension 133 including groove 134 formed on the
exterior surface thereof. Groove 134 cooperates with nipple 136,
formed on flange 138 of control element 130, to guide the control
element during sliding movement in chamber 116 and to prevent
inadvertent removal of element 130 from connector 36. Bore 140 is
formed in flange 138 to vent chamber 142, formed between the flange
and the surface 144 of extension 133, in order to avoid creation of
a pressure pocket in chamber 142 which would resist movement of
element 130.
Control element 130 has interior bore 72 which is adapted to
receive the forward end of a syringe for supplying inflation air to
the device and second bore 76' which provides air communication
between bore 72 and chamber 116. When the physician inserts the
syringe (not shown) within bore 72, he simply urges control member
130 towards closure member 126 whereby nipple 132 compresses member
125 to move it from valve seat 124 and thus permit the passage of
inflation air from the syringe through duct 76' to chamber 116 into
chamber 118 and supply duct 60. In this manner, the multiple
springs and valve members of the prior embodiments are eliminated
and a single simple closure member which maintains itself against
the valve seat is provided. Indicator diaphragm 145 is provided on
connector 36 for indicating when cuff 38 is inflated, as in the
prior embodiments. In addition, indicator 145 may have tab 146 for
rupturing the diaphragm on completion of the administration of
anesthetic so that the inflation air within cuff 38 and chamber 118
may be vented therefrom to facilitate removal of the endotracheal
tube.
FIGS. 7 and 8 illustrate a pair of closure valves 150 and 150'
respectively, which are similar in construction and operation and
like numerals in each of the Figures represent like parts. In each
of these embodiments, connector means 36 is provided with a pair of
chambers 151 and 152, separated by annular wall 153 having duct 154
therethrough. Duct 154 defines valve seat 155 on the side of wall
153 facing chamber 151. Valve control member 156 is slidably
mounted within chamber 152 and includes stem portion 157 extending
through bore 154. Stem 157 in valve mechanism 150 has
semi-spherical closure element 158 mounted thereon for engaging
valve seat 155 to prevent air flow through bore 154, whereas valve
mechanism 150' has flat sealing disc 160 mounted thereon, for
example by a friction fit. In each case, spring 162 is held in
compression between control member 156 and wall 153 within chamber
152. As seen in the drawings, spring 162 maintains the closure
elements in engagement with valve seat 155 to prevent air flow
therethrough. Control member 156 is provided with bore 72 which is
adapted to receive the forward end of a syringe (not shown) for
supplying air to the device. Further, bore 172 provides fluid
communication between bore 72 and chamber 152.
Connecting means 36 of these embodiments is formed to facilitate
supplying air to a syringe during the inflation operation, without
need for the physician to remove the syringe from the device. To
accomplish this end, groove 164 is formed in valve mounting portion
166 of connecting member 36 to provide a flow path for ambient air
along the exterior surface of control member 156. The latter has a
laterally extending bore 168 which provides an air flow path
between groove 164 and bore 72. Thus, when a syringe is inserted
within control member 156, a supply of ambient air is available to
be drawn into the syringe by the physician. The syringe
frictionally engages the inner surface of bore 72 and is thus held
in spaced relation to wall 170. Once the syringe is filled with
air, the physician merely further urges the syringe, and thus
member 156, towards wall 153. This moves bore 168 out of
communication with groove 164 and opens the valve by moving closure
member 158 away from valve seat 155 so that air within the syringe
may be supplied to collar 38. With this construction, the physician
may readily refill the syringe by simply relieving pressure on
member 156 so that bore 168 is again in communication with groove
164. Thus, the inconvenient and time-consuming step of removing the
syringe from the valve for refilling is avoided.
Chamber 151 of valve mechanism 150 is also provided with diaphragm
174, similar in construction to the diaphragms previously
discussed, which indicates when cuff 38 is filled. This diaphragm
is also frangible so that cuff 38 and chamber 151 may be
conveniently vented on completion of the anesthesia procedures. In
valve mechanism 150', diaphragm 174' is positioned at a somewhat
different location, forming a different wall portion of chamber 151
than diaphragm 174.
In FIG. 9 yet another embodiment of the valve structure which may
be used in the present invention is illustrated in a sectional view
similar to FIG. 2. In this case, connector 36 is provided with
extension tube 175 in which valve element 176 is mounted. Element
176 has axially aligned bores 72, 76 therein. Bore 76 provides
valve seat 78 which is adapted to be engaged by closure ball
element 80 held against the valve seat by spring 82, which is held
in compression between the ball and peripheral wall 178 of
connecting means 36. Air supplied from a syringe inserted in bore
72 moves ball 80 away from valve seat 78 to open the valve and to
permit air flow therethrough. End 180 of element 176 adjacent wall
178 is provided, as seen in FIG. 14, with a plurality of passages
182 extending radially therefrom which provide flow paths for
inflation air to annular groove 184 formed therein. Groove 184
communicates with duct 60 to provide air flow to cuff 38 (not
shown). By this construction, accurate alignment of duct 60 with
the fluid port of the control valve is not required. The valve may
be inserted within member 174 in any angular position and yet air
supplied thereto will flow through the valve structure and into
duct 60.
In the embodiment of the device illustrated in FIG. 9, inflation
indicator 186, which comprises an annular sheet of flexible
material fixed in air sealing relation at its edges 188 to
connector 36 and tube 32, is provided. Sheet 186 defines annular
chamber 190 about the periphery of the device. Fluid distribution
groove 58 in connector 36 is provided with laterally extending duct
192 through which inflation air is supplied to chamber 190. In this
manner chamber 42 formed by cuff 38 is in air communication with
chamber 190 so that sheet 186 will expand to give an indication to
the physician utilizing the device that cuff 38 has been
inflated.
As in the prior embodiments, the indicator device may be formed of
a frangible material so that sheet 186 may be conveniently ripped
from the device to vent fluid contained within cuff 38 and duct 60
on completion of the anesthetic procedures.
Another embodiment of valve means adapted for use in the present
invention is shown in FIG. 11. Valve mechanism 200 is illustrated
in which an additional control is provided for the valve wherein
the position of the valve structure may be varied so that the three
operations of intaking air, inflating the cuff, and exhausting the
air may be performed while the syringe is maintained within the
valve. As seen more clearly in FIG. 12, the valve structure of
valve 200 is similar to the structure of valve means illustrated in
FIG. 3, and thus, like numerals have been used therein to represent
like parts. In this case, however, a valve body 202 is provided
with enlarged flange 204 surrounding bore 72. Body 202 is rotatably
mounted within connector means 36 by annular rib 206 which mates
with annular groove 208 formed on the interior wall 210 of chamber
68.
Flange 204 has an inwardly extending stud 212 which is adapted to
engage stop members 214 located at three evenly spaced positions
about arcuate groove 216 formed on surface 218 of connector means
36. Groove 216, as seen in FIG. 14, extends arcuately approximately
180.degree. and stop members 214 are evenly spaced therealong to
correspond with the three operative positions of the valve, that
is, the intake, inflate and exhaust positions.
Valve body 202 has longitudinally extending groove 220 therein
which communicates with laterally extending bore 222 formed in its
peripheral wall. Another generally L-shaped bore 224 is formed in
connector 36, which bore communicates with bore 222 when body 202
is in the intake position (FIGS. 13 and 15) so that an air flow
path is defined from the exterior of the connector means 36 to the
interior of bore 72. In this position, a syringe (not shown) whose
forward portion is inserted within bore 72 may be readily inflated
by the physician. When the syringe is thus inflated, the physician
merely rotates valve body 202 by grasping flange 204 and turning
the entire valve body to the second, or inflate position wherein
bore 220 is moved out of communication with bore 224 and thus is
sealed from the exterior connector 36. The physician then operates
the syringe to force the air contained therein against ball 80 to
move the ball, against the urging force of spring 82, away from
seat 78 to permit air through duct 60 to cuff 38.
Upon completion of the anesthesia procedure, the physician further
rotates valve body 202 to the third or exhaust position wherein the
valve is adapted to vent air from within chamber 68 and cuff 38. In
order to vent chamber 68 and cuff 38, element 202 is provided with
groove 226 formed on the periphery thereof and located
approximately 180.degree. away from groove 220. Thus when flange
204 is rotated to the exhaust position, groove 226 is placed in
alignment with groove 224 (as seen in FIG. 13). In this way a flow
path is provided from the interior of chamber 68 to the exterior of
connecting means 36. In this configuration, duct 222 is positioned
against an annular wall of chamber 68 so that air cannot escape
therefrom. Thus, the physician need not remove the syringe from
bore 72 at any time; the syringe remains conveniently available for
use if additional air must be supplied to cuff 38.
In this embodiment, indicator diaphragm 228, which is similar in
construction to previously discussed diaphragms and forms a wall
portion of chamber 68 to provide an indication of whether or not
cuff 38 has been inflated as desired, is provided.
A somewhat modified endotracheal tube connector 250, adapted for
use in the present invention, is illustrated in FIG. 16. As seen
therein, connector 250 includes a fitting 252 formed integrally
therewith for connection to a source of anesthetic and also
includes a tapered anterior portion 254 adapted to receive the
posterior portion of flexible tube 256. Inner bore 258 of anterior
connector portion 254 includes an undercut section 260 defining an
annular shoulder 262, which undercut portion is adapted to receive
proximal portion 263 of tube 256 with tube end 264 abutting against
shoulder 262.
As in the prior embodiments, the distal portion of tube 256 is
provided with an inflation cuff (not shown) to which air is
supplied through inflation duct 266 formed in the wall of the tube.
Duct 266 is isolated from the interior portion of tube 256 and
opens to an annular groove 268 which constitutes a plenum chamber
for supplying inflation fluid through duct 266 to the cuff.
Proximal portion 270 of duct 266 is closed in any convenient
manner, as for example, by plug 272 to prevent loss of inflation
air through end 270.
Valve member 274, more fully described hereinafter, is mounted on
connector 250 at the junction of fitting 252 and distal portion 254
and provides a convenient mechanism for controlling the supply of
air through duct 266 to the cuff. Valve 274 regulates air flow from
a source thereof, such as a syringe 276 shown in phantom in FIG.
17, through a supply duct 278 formed in connector 250, which duct
provides air communication between valve member 274 and groove 268.
It is noted that by the above described construction, the
endotracheal tube of the present invention is readily assembled
since tube 256 may be inserted within connector 250 in any angular
position, without the necessity of aligning or keying ducts 266 and
278. Accordingly, these ducts may be at positions 180.degree. apart
with respect to each other and yet inflation air is readily
supplied to duct 266.
Valve mechanism 274 is located in chamber 280 formed in connector
250. Chamber 280 communicates with duct 278 and through bore 282,
with bore 284 in which nose 286 of syringe 276 is inserted. Bore
282 defines valve seat 288 at one end thereof adjacent chamber 280.
Closure element 290, which includes a generally conically shaped
main body portion 292 is positioned within chamber 280 and is
adapted to prevent air flow through duct 282 by the sealing
engagement of the periphery of body portion 292 with valve seat
288. Spring 294, held in compression between body portion 292 and
end wall 295 of chamber 280 normally urges closure element 290
against valve seat 288 to prevent air flow through duct 282.
Closure element 290 includes stem portion 296, formed integrally
with main body portion 290, which stem extends through duct 282
into bore 284. Stem 296 is adapted to be engaged by the front end
of nose 286, so that the physician may open and close valve
mechanism 276 by merely urging the syringe against or away from
stem 296. It is noted that stem 296 is of somewhat smaller diameter
than bore 282 so that air may freely flow through that bore when
closure body portion 292 is moved away from seat 288 and against
spring 294 by the engagement of syringe 276 with stem 296. Further,
stem 296 and bore 282 are offset somewhat with respect to the
longitudinal axis of bore 284 so that stem 296 is engaged with a
solid portion of syringe nose 286 and does not interfere with air
flow through the syringe discharge port 298.
It is thus seen that air within syringe 276 is conveniently
supplied to chamber 280 and from that chamber flows through duct
278, chamber 268 and duct 266 to the inflation cuff at the anterior
portion of tube 256. In the event that the first syringe full of
air is inadequate to inflate the cuff, the physician may
conveniently remove nose 286 from bore 284 to refill the syringe
without loss of air from the cuff, since valve member 290
automatically returns to engagement with seat 280 to prevent air
leakage. Thereafter, the inflation process is merely repeated.
Valve mechanism 274 is also provided with flexible diaphragm 275
that is adapted to serve as an indicator to enable the physician to
determine whether the cuff has been inflated to the required
extent. As seen in FIG. 17, the annular exterior wall 300, defining
chamber 280, is provided with an annular groove 302 in which is
seated elastic edge 304 of diaphragm 275. Removable end wall 295 of
chamber 280 is provided with a port 306 which provides air
communication between chamber 280 and chamber 308 defined by
diaphragm 275. The latter, formed in this embodiment in a manner
similar to a balloon i.e., having a rolled edge portion defining
edge 304, is made of somewhat stiffer material than the cuff so
that the cuff inflates to the desired extent before diaphragm 275
expands in the same manner as the diaphragms of the previously
discussed embodiments.
To deflate the cuff in this embodiment of the endotracheal tube,
diaphragm 275 may be removed, as by slipping edge 304 out of groove
302, or a needle or other narrow instrument may be inserted through
bore 84 to engage stem 296 and move body portion 292 away from seat
288, thereby permitting escape of air from the cuff.
It is thus seen that a convenient means has been provided for
controlling the supply and venting of inflation air for
endotracheal tubes. This construction avoids the use of an
inflation cuff such as those in prior devices having relatively
poor sealing members or requiring the use of hypodermic needles for
supplying the inflation air to the cuff. The valve structure is
conveniently located on the connecting means and positioned within
reach of the anesthesiologist and provides an indication to the
physician of whether or not the cuff in the trachea has been
inflated to the desired extent.
Although numerous illustrative embodiments of the invention have
been described herein with reference to the accompanying drawings,
it is to be understood that the invention is not limited to those
precise embodiments, and that various changes and modifications may
be effected therein by one skilled in the art without departing
from the scope or spirit of this invention.
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