U.S. patent application number 09/199540 was filed with the patent office on 2002-01-31 for airway device with provision for coupling to an introducer.
Invention is credited to ARNOLD, RANDALL CHARLES, AUGUSTINE, SCOTT DOUGLAS, MCGRAIL, THOMAS WAYNE.
Application Number | 20020011249 09/199540 |
Document ID | / |
Family ID | 22737966 |
Filed Date | 2002-01-31 |
United States Patent
Application |
20020011249 |
Kind Code |
A1 |
AUGUSTINE, SCOTT DOUGLAS ;
et al. |
January 31, 2002 |
AIRWAY DEVICE WITH PROVISION FOR COUPLING TO AN INTRODUCER
Abstract
A laryngeal airway device for sealing against the laryngeal
opening includes an air tube with proximal and distal ends and a
sealing member attached to the distal end. The sealing member
includes a coupler for coupling the device to an introducer.
Complementing the laryngeal airway device is an introducer that
includes a track for receiving the coupler of the laryngeal airway
device and guiding the sealing member to a sealing position with
respect to the laryngeal inlet. The introducer may include an
epiglottic engager on a distal end to engage the epiglottis and
retain it while the sealing member is being tracked to engagement
with the laryngeal inlet.
Inventors: |
AUGUSTINE, SCOTT DOUGLAS;
(BLOOMINGTON, MN) ; ARNOLD, RANDALL CHARLES;
(MINNETONKA, MN) ; MCGRAIL, THOMAS WAYNE; (CHASKA,
MN) |
Correspondence
Address: |
TERRANCE A MEADOR
GRAY CARY WARE & FREIDENRICH
401 B STREET
SUITE 1700
SAN DIEGO
CA
92101
|
Family ID: |
22737966 |
Appl. No.: |
09/199540 |
Filed: |
November 25, 1998 |
Current U.S.
Class: |
128/207.15 |
Current CPC
Class: |
A61B 1/267 20130101;
A61M 16/04 20130101; A61M 16/0409 20140204; A61M 16/0488 20130101;
A61M 2210/0656 20130101 |
Class at
Publication: |
128/207.15 |
International
Class: |
A61M 016/00 |
Claims
We claim:
1. A laryngeal airway device, comprising: an air tube with two
ends; a sealing member mounted to the air tube, near one end of the
tube, and including a distal end; and a coupler on the sealing
member near the distal end.
2. The device of claim 1, wherein the sealing member includes: a
compressible pad; and a support member posterior to pad, the
support member including two sides and a distal end, the coupler
including a flexible flange extending forwardly from the distal end
of the support member.
3. The device of claim 2, wherein the flexible flange has a first
position in which it extends forwardly from the distal edge and is
moveable from the first position to a second position.
4. The device of claim 3, wherein the flexible flange includes a
tab having a lateral extent that is less than a lateral extent of
the distal edge and a pedestal, narrower than the tab and the
distal edge, connecting the tab and the distal edge.
5. The device of claim 1, wherein the sealing member includes: a
compressible pad; and a support member posterior to the pad, the
support member having two sides and a distal end, the coupler
including a pair of opposing flanges extending upwardly from the
sides with portions extending medially toward each other.
6. A sealing airway device, comprising: an air tube with two ends;
a sealing member mounted to the air tube, near one end of the air
tube, and including a distal end; a passageway opening through the
sealing member; and a coupler on the sealing member near the distal
end.
7. The device of claim 6, wherein the coupler includes a flexible
flange extending forwardly from the distal end.
8. The device of claim 6, wherein the coupler includes a
compressible pad and a support member posterior to the pad, the
support member having two sides and a distal end, the coupler
including a pair of opposing flanges extending upwardly from the
sides with portions extending medially toward each other.
9. A combination for airway management, comprising: a sealing
airway device that includes an air tube with two ends, a sealing
member mounted to the air tube near one end of the tube and
including a distal end, a passageway opening through the sealing
member, and a coupler on the sealing member near the distal end; an
introducer that includes a blade with a proximal end on a first
portion of the blade and a distal end on a second portion of the
blade, anterior and posterior sides, and a track on the posterior
side extending from near the proximal end to near the distal end;
whereby the coupler may couple to the track for tracking the airway
sealing device along the posterior side of the introducer.
10. The combination of claim 9, wherein the introducer is
substantially Jshaped.
11. The combination of claim 9, wherein the introducer comprises a
laryngoscope blade.
12. An introducer for tracking a sealing airway device into the
throat of a person, comprising: a shaped section with a first
portion with a proximal end and a second portion with a distal end;
anterior and posterior sides; and a track on the posterior side
extending from near the proximal end to near the distal end.
13. The introducer of claim 12, wherein the shaped section has a
substantially J-shape.
14. The introducer of claim 12, wherein the introducer includes a
laryngoscope blade.
15. The introducer of claim 12, wherein the track includes a pair
of opposing wall sections that extend longitudinally on the
posterior side and a pair of medially-extending sections, each
medially-extending section extending toward the other
medially-extending section along an edge of a respective wall
section.
16. The introducer of claim 12, wherein the track includes a pair
of opposing wall sections that extend longitudinally on the
posterior side and a pair of laterally-extending sections, each
laterally-extending section extending away from the other
laterally-extending section along an edge of a respective wall
section.
17. The introducer of claim 12, further including a epiglottic
engager mounted on the shaped section near the distal end.
18. The introducer of claim 17, wherein the epiglottic engager is
pivotally mounted on the shaped section near the distal end.
19. A blade device for seating in an airway, comprising: a shaped
section with anterior and posterior surfaces, a proximal end, and a
distal end; and an epiglottic engager mounted to the shaped section
near the distal end.
20. The blade device of claim 19, wherein the epiglottic engager is
pivotally mounted to the shaped section near the distal end for
moving between a first position near the posterior side and a
second position away from the posterior side.
21. The device of claim 19, wherein the epiglottic engager has a
substantially triangular shape with an apex and a base, the distal
end has a pair of slots with the apex received in a first slot and
the base received in a second slot, the epiglottic engager further
including a substantially flat section that projects beyond the
base toward the distal end on the base of the shaped portion.
22. The device of claim 19, wherein the epiglottic engager is
formed of a metal material.
23. The device of claim 19, wherein the epligottic engager is
formed of a non-metal material.
24. The device of claim 19, wherein the epligottic engager is
formed of a plastic material.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application contains subject matter that is related to
the following patent applications:
[0002] U.S. patent application Ser. No. 08/730,791, filed Oct. 16,
1996, for LARYNGEAL AIRWAY DEVICE;
[0003] U.S. patent application Ser. No. 08/885,682, filed Jun. 30,
1997, for LARYNGEAL AIRWAY DEVICE;
[0004] PCT Application No. US97/16838, filed Sep. 24, 1997, for
LARYNGEAL AIRWAY DEVICE; and
[0005] U.S. patent application Ser. No. ______, filed on even date
herewith, for AIRWAY DEVICE WITH PROVISION FOR LATERAL ALIGNMENT,
DEPTH POSITIONING, AND RETENTION IN AN AIRWAY.
BACKGROUND OF THE INVENTION
[0006] 1. Field of the Invention
[0007] This invention is concerned with the management of a human
airway in order to control respiration. More particularly, the
invention concerns a device that brings an airway tube reliably and
safely into communication with the laryngeal opening, the upper end
of the trachea, which is the breathing passageway that leads to the
lungs. The device seats in the throat immediately adjacent the
laryngeal opening, tensions and erects the laryngeal opening, and
seals with it to provide a channel through the airway tube for
artificial ventilation of the lungs. In particular, the invention
concerns a laryngeal airway device that can be coupled to an
introducer and guided to this position through the throat. For this
purpose a tracking introducer is provided.
[0008] The invention also concerns a laryngeal blade used to access
the laryngeal anatomy in order to support access to the laryngeal
opening by an airway device.
[0009] Another concern of interest in consideration of the
invention is engagement and control of the epiglottis as an aid in
gaining access to the laryngeal anatomy.
[0010] 2. Description of the Related Art
[0011] An airway device facilitates ventilation of the lungs of a
person. The purpose of such a device is to provide an air pathway
from an external air source, through the mouth, throat, and
trachea, to the lungs. Additionally, some airway devices provide a
seal with the throat of a person, which allows positive pressure
ventilation and which may also prevent the leakage of stomach
contents into the trachea (aspiration).
[0012] It is useful to divide airway devices into two categories:
those that pass through the vocal chords and are commonly referred
to as "tracheal tubes", and those that lodge in the throat, above
the vocal chords, and are commonly referred to as "airways". We
shall limit "airway" to refer to a device that provides a fluid
pathway from outside the mouth of a person to a location above the
vocal chords.
[0013] In the variety of airway devices that are available, some
merely support the tissue of the pharynx (throat), particularly the
tongue, creating a passageway so that air can pass by and into the
pharyngeal space toward the laryngeal opening, which is the opening
into the voice box. Other airway devices include a tube that
provides an air channel to a location near the laryngeal opening.
Still other airway devices add a sealing means to the distal end of
the tube in order to provide some degree of sealing between the
tube and the airway of the person.
[0014] A laryngeal mask is an example of a sealing airway device.
U.S. Pat. Nos. 4,509,514; 4,995,388; and 5,355,879 are descriptive
of a laryngeal mask. A laryngeal mask includes an inflatable
doughnut-shaped balloon which, when inflated, circles the laryngeal
opening and creates a fluid seal between the outside of the
inflated balloon and the tissues in the pharyngeal structures of
the throat that surround the larynx.
[0015] Another sealing airway device, described in U.S. Pat. No.
5,513,627, includes an inflatable balloon fixed on the distal end
of a tracheal tube that is inserted into and inflated within the
trachea, forming a seal against the interior walls of the
trachea.
[0016] In the first three cross-referenced patent applications, all
assigned to the assignee of this application and incorporated in
their entirety by this reference, a sealing member is mounted near
the distal end of an airway tube to seal directly with the rim of
the laryngeal opening, portions of the epiglottis, and the
sidewalls of the larynx. This unique airway creates a fluid seal
directly with the larynx.
[0017] Accurate placement of an airway device can be a very
difficult task for the clinician and a traumatic event for the
patient. When a patient is under anesthesia, or has lost
consciousness for other reasons, the tongue and tissues of the
throat relax and fall back, effectively obstructing the flow air
from the mouth or nose to the laryngeal opening. This same
relaxation of the tongue makes it difficult to pass an airway
device along the back of the tongue, into the throat. Frequently,
the clinician's fingers must be inserted into the patient's mouth
to displace the tongue or push the airway device around the corner
at the posterior pharynx. Furthermore, the highly variable and
extremely flexible anatomy surrounding the larynx make accurate
positioning of an airway device very difficult. In particular, the
epiglottis must be correctly positioned in order to introduce and
seat an airway device that effectively seals against the laryngeal
opening. An epiglottis that covers the larynx will prevent a proper
seal. Finally, the mucosal tissues lining the mouth, throat, and
larynx are very fragile. Devices that are inserted blindly
frequently scrape these tissues causing bleeding, sore throats, and
throat infections.
[0018] Accordingly there is need for easy guidance of an airway
device through the mouth and throat that will result in accurate
positioning of the device with respect to the larynx.
[0019] Accordingly, there is a need for a device that will provide
access to the laryngeal anatomy for the purpose of airway
management.
[0020] Accordingly, there is a need for a laryngeal access device
with provision for engagement and control of the epiglottis.
SUMMARY OF THE INVENTION
[0021] A sealing laryngeal airway device forms a fluid seal against
the rim of the laryngeal opening, that is, against the larynx
itself. The invention provides for guiding or tracking such a
device through the throat to the laryngeal opening.
[0022] The invention provides an introducer that provides access to
laryngeal anatomy for the introduction of an airway device in the
laryngeal anatomy.
[0023] The invention provides an epiglottic engager on a laryngeal
access device.
[0024] The invention contemplates an introducer embodied as a
relatively stiff blade-like device that is curved in longitudinal
section. In a preferred embodiment, the distal end of the
introducer is adapted to center on the midline hyo-epiglottic
ligament and engages under the hyoid bone for accurate positioning.
Alternately, the introducer can comprise a laryngeal blade. The
introducer includes a track extending from a location near a
proximal handle to a location near a distal end of the introducer.
A coupling or engaging mechanism is provided near the distal end of
the laryngeal airway device for slidably coupling the device to the
track of the introducer. The laryngeal airway device is advanced
along the track, which guides the sealing member to the laryngeal
opening. At this point, the coupling mechanism disengages from the
track and the introducer may be withdrawn, leaving the laryngeal
airway device seated in its correct position for operation.
[0025] An alternate embodiment of the introducer includes a
laryngeal scope blade having a posterior surface with a track.
[0026] An auxiliary feature to the introducer is an epiglottic
engager that captures the epiglottis during airway
introduction.
BRIEF DESCRIPTION OF THE DRAWING
[0027] FIG. 1 is a perspective view of a laryngeal airway device
having a coupler for engaging an introducer according to this
invention.
[0028] FIG. 2 is an exploded view of the laryngeal airway device of
FIG. 1.
[0029] FIG. 3 is a side elevation view of the laryngeal airway
device of FIG. 1.
[0030] FIG. 4 is a perspective view of a preferred embodiment of an
introducer according to this invention.
[0031] FIG. 5 is a side elevation view of the laryngeal airway
device of FIG. 1 coupled to the introducer of FIG. 4.
[0032] FIG. 6 is a sectional drawing taken along line 6-6 of FIG.
5.
[0033] FIG. 7 is a plan view of the posterior side of the laryngeal
airway device of FIG. 1 coupled to the introducer of FIG. 4.
[0034] FIG. 8 is a magnified side view of a portion of the distal
end of the laryngeal airway device of FIG. 1.
[0035] FIG. 9A is a magnified side sectional view of the distal end
of the introducer taken along line 9-9 of FIG. 7 showing a pivotal
epiglottic engager.
[0036] FIG. 9B shows an alternate embodiment of an epiglottic
engager in a plan view of the posterior side of the introducer of
FIG. 4.
[0037] FIG. 9C is a magnified side sectional view of the distal end
of the introducer taken along line 9C-9C of FIG. 9B.
[0038] FIG. 10A is a partial cutaway perspective view of the
anatomy of the throat with the laryngeal airway device of FIG. 1
positioned in the anatomy.
[0039] FIG. 10B is a schematic lateral cross-sectional
representation of the anatomy of the throat taken along line B-B of
FIG. 10A.
[0040] FIGS. 11-14 are schematic side cross-sectional
representations of the anatomy of the throat showing the operation
of the introducer of FIG. 4.
[0041] FIGS. 15-18 are schematic side cross-sectional
representations of the anatomy of the throat showing the
introduction and positioning of the laryngeal airway device of FIG.
1.
[0042] FIGS. 19A, 19B and 19C illustrate alternate embodiments of
features of the laryngeal airway device coupler and the introducer
track.
[0043] FIGS. 20A-20D show various views of an alternate embodiment
of the introducer.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0044] A laryngeal airway device is designed to form a fluid seal
against and within the rim of the laryngeal opening. Because the
seal is against and within the rim of the larynx itself, and not
with the pharyngeal structures surrounding the larynx, introduction
of the device must be very accurate. The invention provides for
guidance of a laryngeal airway device to its sealing position
against the larynx. It should be noted however that the mechanisms
and techniques that track or guide the laryngeal airway device to
the laryngeal inlet could also work well with other airway devices,
including a pharyngeal airway device. Therefore, although the
following description is directed to a laryngeal airway device,
this is not intended to so limit the application of the
invention.
[0045] FIGS. 1, 2 and 3 illustrate an example of a laryngeal airway
device 10 that incorporates a feature of our invention. The
laryngeal airway device 10 includes a flexible air tube 12 having
first (proximal) and second (distal) ends 13 and 14, respectively.
Preferably the tube 12 has a curved shape that conforms to the
contour of the back of the tongue. A connector 18 is attached to
the proximal end 13 to connect the tube to a ventilating means,
which is not shown. A sealing member 15 is attached to the tube 12
near its distal end 14. The sealing member 15 includes a support
member 16 and a compressible foam pad 17.
[0046] In more detail, the support member 16 has an upper
(proximal) edge 20 and an anterior support surface 21, a distal end
22, and sides 23. The anterior support surface 21 has a generally
sigmoid shape in a longitudinal section. In a lateral section, the
shape of the anterior support surface 21 is generally flat,
although there may be some variation to accommodate design,
manufacturing, or operational considerations. The lower (distal)
third of anterior support surface 21 extends to the distal end 22.
Laterally of the distal end 22 are a pair of opposing cricoid
retainers embodied as lateral flanges 24 that rise upwardly along
the sides 23 from the distal portion of the anterior support
surface 21. A coupler or track-engaging mechanism is provided in
the distal portion of the support member 16. In these figures, this
mechanism is embodied as a flexible track-engaging flange 25 that
extends forwardly of the distal end 22. The flexible track-engaging
flange 25 may perform one, or two useful functions: esophageal
tracking and coupling to an introducer. Both are described below.
The structure of the flexible track-engaging flange 25 includes a
tab 26 that is connected to the distal end 22 by a pedestal 27. The
lateral extent of the tab 26 at its widest section is preferably
less than the width of the distal end 22 of the support member 16.
The pedestal 27 is narrower than both the tab 26 and the distal end
22. The air tube 12 is enabled to project through the anterior
support surface 21 of the support member 16 by a tubular,
"snout-like" extension 28 that is a hollow cylinder having proximal
and distal ends 28a and 28b, respectively. The tubular extension 28
is fixed to the support member 16 and the distal end 14 of the air
tube 12 is received and fixed in the proximal end 28a of the
tubular extension 28. The tubular extension 28 has a generally
conical-like shape, with the narrower radius found at the distal
end 28b and the wider radius at the proximal end 28a. The tubular
extension may also be entirely cylindrical, or partially tubular,
resembling a hood. Manifestly, the tubular extension 28 may be a
shaped, molded portion of the air tube 12, or a piece that is
separate altogether from the air tube 12 but attached to the distal
end 14. The tubular extension 28 may also be slit to allow passage
of an endoctraceal tube.
[0047] The compressible pad 17 preferably has a pear-like shape
with an upper, or proximal portion 30, an anterior surface 31, and
a lower or distal portion 34. The upper portion 30 is relatively
wider than the lower portion 34. The compressible pad has an
anterior surface 31. The upper portion 30 includes a hole 35
defining a passageway 35a in the sealing member 15 that is centered
in the upper portion 30 and on a longitudinal midline M of the pad
17. The hole 35 opens through the anterior surface 31 and the
passageway 35a extends through the pad 17, aligned longitudinally
with the distal end 14 of the air tube 12. The tubular extension 28
is disposed in the passageway 35a. A slot, elongated hole, notch,
or depression 36 is provided in the anterior surface 31, preferably
centered on the midline M, and positioned between the hole 35 and a
distal end 37 of the compressible pad 17. The length of the
compressible pad 17 that extends from a proximal end 33 to the
distal end 37 is such that, when the pad 17 is joined to the
support member 16, the distal end 37 of the pad is positioned
between the lateral flanges 24, set back from the distal end 22.
This leaves open a channel defined laterally between distal
portions of the lateral flanges 24 and longitudinally between the
distal end 37 of the compressible pad 17 and the distal end 22 of
the support member.
[0048] Preferably, and for illustration and example only, the
support member 16 is a flexible plastic part that may be fabricated
by molding 85 durometer PVC material. In this case, the air tube 12
should be made of somewhat stiffer material, for example 90
durometer plastic. The anterior support surface 21 has the
generally sigmoid shape described above. Alternate embodiments of
the anterior support surface 21 may be substantially flat, convex,
or concave in longitudinal section.
[0049] The compressible pad 17 is preferably made by molding a
closed cell foam having a density of about seven pounds to make the
pad soft and conformable. When the compressible pad 17 is
integrated with the support member 16, its anterior surface 31
takes on the sigmoid shape of the support member's anterior support
surface 21. That is, the anterior surface 31 has a sigmoid contour
imposed on it in a longitudinal section, but is substantially flat
in opposing lateral sections that extend from the midline M
laterally to the sides of the pad 17.
[0050] The sealing member 15 may be fabricated by molding or die
cutting the elements 16 and 17 and then combining them into a
unitary structure by attaching the pad 17 to the anterior surface
21 of the support member 16 by gluing, heat bonding, or ultrasonic
bonding, by some form of riveting, by a combination of any of these
methods, or by any other equivalent that will yield an integrated,
unitary structure in which the foam pad 17 has a soft, compressible
characteristic, while the support member 16 is relatively more
rigid than the pad 17, yet with a flexibility in one or more of its
elements that allows bending during use.
[0051] Although the sealing member 15 is illustrated and described
as comprising two parts, it should also be evident that, with a
selection of materials and methods, this member can comprise one
part with two portions in which the materials and structures of one
portion transition continuously or abruptly to the materials and
structures of the other portion.
[0052] As is best seen in FIG. 3, an inflatable balloon 38 is
disposed on the posterior side of the support member 16, extending
generally between the proximal end 28a of the tubular extension 28
and the distal end 22 of the support member 15. A small tube 39 is
provided for inflating the balloon 38. The balloon 38 may be
provided to compensate for unusual variations in airway anatomy. It
will not be necessary to inflate the balloon 38 in all patients in
order to effect an airway seal.
[0053] Refer now to FIGS. 4, 5, 6 and 7 for an understanding of a
preferred embodiment of an introducer with which the laryngeal
airway device of FIGS. 1-3 is used. The introducer, indicated by
generally 11, is a relatively stiff plastic or metal blade-like
device having a straight portion and a curved portion. Preferably,
though not necessarily the shape may be that of a capital "J". A
first (proximal) end 40 of the introducer 11 transitions to a
generally elongate proximal section with an anterior surface 42 and
a posterior side 45. A handle 40a is provided at the proximal end
40. A second (distal) end 41 terminates the sharp "hook-shaped"
portion of the "J"-shape of the introducer. Preferably, the
introducer 11 is substantially flattened in cross-section.
Preferably, although not necessarily, the distal end 41 preferably
includes an indentation 43 on either side of which is a rounded
protuberance 44. The indentation 43 is designed to accommodate the
midline hyo-epiglottic ligament, while the protuberances 44 are
designed to engage under the hyoid bone for accurate positioning of
the introducer 11. These means of positioning have been described
in U.S. Pat. Nos. 4,832,020 and 5,042,469, which are owned by the
assignee and incorporated by this reference.
[0054] Referring to FIGS. 4, 5, 7, and 9A, an epiglottic engager,
disposed on the distal end 41 of the introducer 11 is shown.
Preferably this is a moveable epiglottic engager 52 pivotally
attached to the distal end 41 of the introducer 11. As best seen in
FIG. 9A, the epiglottic engager 52 has an elongate flattened
forward section 53 that transitions to a closed triangular section
54 with an apex 55 and an opposing base 56. The apex 55 and base 56
are received in slots 42s through the posterior side 45 near the
distal end 41 of the introducer 11. The forward section 53 projects
beyond the base 56 toward the distal end 41 of the introducer 11.
As best seen in FIG. 9A, the moveable epiglottic engager 52 can
pivot between a fully extended position indicated by the solid
lines and a closed position indicted by the dashed lines.
[0055] FIGS. 9B and 9C illustrate an alternate embodiment
epiglottic engager that is flexible and somewhat moveable, but not
pivotable. As shown in these figures, the alternate embodiment
epligottic engager 52a has an elongate flattened forward section
53a that transitions to a rear section 54a that includes a raised
rectangular section 55a. In the distal region of the introducer 11,
the anterior surface 42 has a first, lower extension 42a over or
apart from which is a raised section 42b having a rectangular
cutout 42r whose length and width are slightly greater than the
corresponding dimensions of the raised rectangular section 55a. A
space is formed between the lower section 42a and the upper section
42b within which the rear section 54a of the epiglottic engager 52a
is received, with the raised rectangular section 55a being received
in the rectangular cutout 42r. The forward section 53a projects
forwardly form the rear section 54a, toward the distal end 41 of
the introducer 11. While the alternate embodiment epiglottic
engager 52a is not pivotable, it is flexible toward and away from
the distal end 41.
[0056] Preferably either epiglottic engager is made of the same
material as the blade. However, it is contemplated and may be
desirable, that the engager be a different material, such as
plastic. It should also be understood that the engager could be a
removable component to accommodate substitution of differently
dimensioned engagers.
[0057] FIGS. 1, 5, 6 and 7 illustrate elements of the device 10 and
the introducer 11 that permit these two elements to operate
cooperatively in solving the problem of tracking or guiding the
device 10 into alignment with the laryngeal opening. The flexible
track-engaging flange 25 on the distal end 22 of the sealing member
15 couples to a track 46 formed on the posterior side of the
introducer 11. As shown best in FIGS. 5-7, the track 46 includes
two opposing slide rails that are generally "U"-shaped and are
formed by upwardly-extending wall portions 47, which extend
longitudinally on the posterior side 45. The wall portions 47
transition to medially-extending sections 48. There is a gap 49
between the medially-extending sections 48.
[0058] The device 10 is coupled to the introducer 11 by orienting
the compressible anterior surface 31 of the sealing mechanism
toward the posterior side of the introducer 11 and inserting the
flange 25 between the "U"-shaped slide rails on the posterior side
of the introducer 11 where the rails begin at 50 near the proximal
end 40. The opening 49 captures the edges of pedestal 27, while the
tab 26 of the flange 25 is retained between the slide rails. When
the device is pushed toward the distal end 41 of the introducer 11,
the air tube 12 is rotated to place the distal end 28b of the
tubular extension 28 toward the posterior side, within the opening
49 between the slide rails. When pressure directed toward the
sealing member 15 is applied on the tube 12, the device is
advanced, sealing member 15 first, along the posterior side of the
introducer 11 towards its distal end 41. When the flange 25 emerges
from between the slide rails at the opening 51 where the
medially-facing portions 48 of the slide rails taper toward the
vertical portions 47, the flange 25 is released from the rail track
of the introducer 11 and the device 10 is uncoupled from the
introducer 11.
[0059] In this exemplary construction of the device 10, and as
illustrated in FIG. 8, the material of which the support member 16
is made imparts a flexibility that permits the flange 25 to rotate
between a first position indicated by the solid lines in FIG. 8 and
a second position that is indicated by the dashed line in FIG. 8.
In the first position, the device 10 is not coupled to the
introducer 11. However, in the second position, the flange 25 has
been engaged between the slide rails of the introducer 11 and the
device 10 has been advanced to the point just before the flange 25
is released.
[0060] Positioning of the Laryngeal Airway Device
[0061] FIG. 10A is a cutaway perspective view of the anatomy of a
throat with the laryngeal airway device 10 seated against the
laryngeal opening 60. This figure and FIG. 10B are provided for an
explanation of how the laryngeal airway device is positioned and
retained in the throat, although these functions of the device are
not necessary to the practice of this invention.
[0062] FIG. 10B is a schematic lateral cross-sectional
representation of the laryngeal anatomy taken along line B-B of
FIG. 10A. The direction of the view is toward the throat, from
behind the sealing member 15. The view is schematic and imaginary,
assuming that the sealing member is substantially transparent, with
the outlines of its major components--the support member 16 and the
compressible pad 17--indicated by heavy lines. In these views, the
rim of the laryngeal opening is indicated by reference numeral 60,
the inter arytenoid notch by reference numeral 62, the
aryepiglottic folds by 64, the vocal chords by 66, the esophagus by
68, and the epiglottis by 70.
[0063] With respect to lateral positioning, the two opposing,
substantially parallel lateral flanges 24 extend anteriorly and
seat on each side of the cricoid cartilage which is disposed toward
the bottom of the larynx, distal to the rim 60. When the cricoid
cartilage is cradled between the lateral flanges 24, it is
contained within the channel defined between the distal portions of
by these elements, which assures lateral alignment of the tubular
extension 28 within the laryngeal opening with respect to the vocal
chords 66. FIGS. 1, 2, and 3 illustrate the lateral flanges 24 as
being located on the lateral edges 23 of the anterior supporting
surface 21. In this illustration, the lateral flanges 24 extend for
only part of the length of the sides; however, they may extend for
shorter, or longer distances along the sides. In a side elevation
view, the ridges may assume many shapes including, but not limited
to, wall-like, rounded, square or rectangular, triangular,
truncated triangular, or a combination of these shapes or any
shapes that are equivalent and that serves the purpose of lateral
retention. When viewed elevationally from the front of the support
member 16, the lateral flanges 24 may have many shapes including,
but not limited to, a wall, a tab, or a cylinder.
[0064] In considering cephalad-caudad positioning, refer to FIGS.
1, 3, and 10. Recall the sigmoid shape of the anterior support
surface 21, which is imposed on the anterior surface 31 of the
compressible pad 17. The lower portion of the sigmoid that is
described by the lower or distal portion 34 of the compressible pad
is designed to seat between the larynx and the posterior pharynx,
stabilizing the device 10. The lower portion of the support member
16, that is, the portion generally just above the distal end 22 to
the end of the flange 25, is preferably angled posteriorly when
molded. The posterior angle assures that the flange 25 and distal
end 22 will be applied directly against the posterior wall of the
pharynx when the airway 10 is advanced into its position of use.
The midportion of the sigmoid shape is angled to abut the angled
rim of the laryngeal opening 60, along the ary-epiglottic folds.
The upper portion of the sigmoid shape is flattened to seal against
the posterior side of the epiglottis, within the laryngeal opening.
The "snout-like" tubular extension 28 protrudes through the hole
35, beyond the anterior surface 31, into the laryngeal opening 60.
This snout helps create a fluid seal against the larynx by holding
the laryngeal tissues out of the distal opening 28b, to prevent
obstruction of air flow. As stated above, the tubular extension 28
is preferably shaped like a truncated cone, with its wide base
attached to the distal end 14 of the air tube 12. The narrow distal
end 28b is opened to allow air flow and it is this part that
penetrates most deeply into the laryngeal opening 60.
[0065] Accurate cephalad-caudad depth placement is provided by the
combination of the "snout-like" distal end 28b of the tubular
extension 28 and the lower part 34 of the anterior surface 31 of
the sealing member. This combination creates a "hook". The angle
.PHI. (FIG. 3) between the distal end 28b of the tubular extension
28 and the lower anterior surface portion 34 is preferably an acute
angle, greater than 0.degree. and less than 90.degree.. The base of
the notch 62 formed between the arytenoid cartilages is made of the
arytenoidous muscle overlaying the cricoid cartilage. These
structures are very firm and assure a positive end-point when
contacted with a longitudinal force. The hook described by the
acute angle .PHI. is designed to catch on the cartilage and muscle
between the arytenoid cartilages, on the posterior edge of the
laryngeal opening. With reference to the "cut pipe" analogy
described above, the hook described by the angle .PHI. engages over
the posterior rim of the laryngeal opening, which is the obtuse
angled edge of the rim. With the distal end 28b of the tubular
extension 28 lodged inside the laryngeal opening, the hook cannot
slip out distally or become displaced laterally when longitudinal
pressure is applied to the airway. The arytenoid depression 36 and
the anterior surface 31 assists in this positioning by receiving
small comiculate tubercles that are on the posterior side of the
larynx and that are near the arytenoid notch. The tubercles are
received in the depression 36, and assist in positioning the
laryngeal airway device 10 longitudinally in the laryngeal
opening.
[0066] Referring once again to FIGS. 10A and 10B, the
cephalad-caudad positioning of the laryngeal airway device 10 may
be understood. As shown in this figure, the inter arytenoid notch
62 is positioned between the tubular extension 28 and the distal
portion 34 of the compressible pad 17. Although not shown in this
view, the distal end 28b of the tubular extension 28 is located
above the vocal chords 66. In addition, the arytenoid depression 36
has received the forward portion of the inter arytenoid notch 62
that includes the comiculate tubercles. This provides space in
which the tubercles can be received, which enables the posterior
side of the inter arytenoid notch to relax somewhat and move with
the bottom portion of the tubular extension 28.
[0067] Retention of the Laryngeal Airway Device
[0068] In FIG. 3, there is shown an edge surface 88 on the proximal
edge 33 of the compressible pad 17 and a surface 89 that extends
from the proximal end 28a of the tubular extension 28 across the
distal end 14 of the tube 12. The edge surface 88 and the tube
surface 89 receive the tissues on the back portion of the tongue
when the sealing member 15 has been advanced to seal against the
laryngeal opening with lateral and depth positioning as described
above. At this location, the back portion of the tongue relaxes,
draping over the edge surface 88 of the proximal edge 33 and
hanging down onto and around the surface 89. The rough texture of
the surface of the tongue prevents the compressible material at the
edge surface 88 from easily sliding across the surface of the
tongue. This retains the airway in tight approximation with the
larynx by anchoring it with the base of the tongue. The edge
surface 88 that is presented by the structure of the distal portion
of the laryngeal airway device 10 capitalizes on the flexibility of
the tongue to capture the airway at the proximal edge 33 where the
contact between the anchored base of the tongue and the edge
surface 88 retains the edge 33 and prevents the airway 10 from
being ejected from its correct positioning against the rim of the
laryngeal opening.
[0069] Operation According to the Invention
[0070] The cooperative operations of the laryngeal airway device
and the introducer will now be explained with reference to FIGS. 11
-18.
[0071] Initially, in FIG. 11, the introducer 11 is inserted, distal
end 41 first, through the mouth, traversing the tongue 74 where, in
FIG. 11, one of the rounded protuberances 44 is shown approaching
the sharp curvature 75 at the back of the tongue. As the distal end
of the introducer 11 advances, the flattened forward section 53 of
the epiglottic engager 52 is rotated toward the posterior side 45
near the distal end 41 by contacting the back of the throat. In
FIG. 12, as the distal end 41 of the introducer 11 passes the sharp
curve 75 at the back of the tongue 74, the narrow dimensions of the
throat force the structure of the distal end 41 against the back of
the tongue 74, lifting the lower tissues of the tongue away from
the epiglottis 70. At this point, the flattened forward section 53
of the epiglottic engager 52 is fully rotated toward the distal end
41, between the rounded protuberances 44. In FIG. 13, the
introducer 11 is pulled upwardly as it is advanced into the throat,
further raising the tissue at the base of the tongue 74 and
widening the throat, allowing the flattened forward section 53 of
the epiglottic engager 52 to pivot away from the distal end 41
toward the back of the throat. As the distal end 41 of the
introducer 11 is advanced to the position shown in FIG. 14, the
epiglottis 70 is trapped between the distal end of the introducer
11 and the flattened forward section 53 of the epiglottic engager
52. This retains the tip of the epiglottis 70 upwardly, keeping it
out of the space in the throat through which the sealing member of
the laryngeal airway device must pass. At this point, the
indentation 43 of the distal end 41 of the introducer has received
the hyoepiglottic ligament, while the protuberances 44 have been
engaged under the hyoid bone to position the introducer 11. In FIG.
15, the laryngeal airway device 10 has been coupled to the
introducer 11, with the tab 26 engaged in the track 46. The sealing
member 15 is oriented as described above. The laryngeal airway
device 10 is advanced along the introducer 11 over the tongue
toward the curve 75 at the back of the tongue 74. In FIG. 16, the
laryngeal airway device 10 has been advanced to the point where the
flange 25 has emerged from the opening 51 at the distal end of the
track 46. As the distal end of the laryngeal airway device 10 is
advanced further into the throat, the flange 25 springs back to its
first position with the tab 26 angled posteriorly toward the back
of the throat. At this position, it can perform esophageal
tracking. Referring to FIGS. 17 and 18, as the laryngeal airway
device 10 is advanced further into the throat, it eventually seats
against the rim 60 of the laryngeal inlet, with the distal end 28b
of the tubular extension 28 extending within the laryngeal inlet
and the anterior surface 31 of the compressible pad 17 engaging and
sealing against the rim 60, and extending partly into the laryngeal
opening in the vicinity of the distal end 28b. At the same time,
the distal end of the sealing member 15 has tracked down the back
of the throat with the tab 26 of the flange 25 tracking toward the
esophagus 68. At this point, the above-described features of the
laryngeal airway device have aligned and positioned it laterally
and along the depth axis of the larynx. Now, the introducer 11 is
withdrawn, leaving the laryngeal airway device 10 seated.
Withdrawal of the introducer causes the tongue to drape down over
the edge surface 88 and the surface 89 which retains the laryngeal
airway device in the manner described above.
[0072] Clinical experience has shown the inventors that optimal
lateral positioning with the laryngeal airway device 10 can be
accomplished with a specific maneuver. Once the device 10 is
positioned, with the flange 25 located between the larynx and the
posterior wall in the pharynx in the upper reaches of the esophagus
68, the proximal end 13 of the laryngeal airway device 10 is
grasped. The laryngeal airway device 10 is pulled very slightly out
of the mouth against the tension of the tongue and then pushed back
in. This maneuver is known as the "Arnold maneuver". The device 10
is not pulled so far out as to cause disengagement with the
epiglottis 70 but merely to partially disengage the anterior
surface 31 from the rim 60 of the laryngeal inlet. When the device
10 includes the distal end 28b, the Arnold maneuver disengages the
tip of the distal end 28b from an arytenoid cartilage that may be
obstructing the opening 60. On reinsertion, the distal end 28b is
unobstructed and lies within the laryngeal inlet 60. The Arnold
maneuver in conjunction with a device 10 that includes the lateral
flanges 24 or their equivalent has been shown to dependably orient
the device 10 in the lateral dimension with respect to the larynx.
If the device 10 includes the snout like distal end 28b, the Arnold
maneuver dependably places the distal end 28b within the laryngeal
inlet 60 and clears tissue that may obstruct airflow.
[0073] If necessary to achieve a desired level of positive
pressure, the seal that the laryngeal airway device makes with the
laryngeal inlet may be assisted by inflation of the balloon 38
through the tube 39. This may follow the Arnold maneuver, if
indicated. Inflation of the balloon 38 will rotate the sealing
member anteriorly with respect to the laryngeal opening, further
tensioning the opening and further urging the anterior surface of
the compressible pad into sealing engagement against the
opening.
[0074] Alternate Embodiments
[0075] The tracking or guiding feature of this invention may be
implemented in many ways. FIGS. 19A, 19B and 19C show an alternate
embodiment of this feature. In this alternate embodiment, the
coupler or rail-engagement mechanism on the sealing member of the
laryngeal airway device includes a pair of opposing brackets 80 on
the distal portion of the sealing member, near the edges 23,
between the lateral flanges 24 and the distal end 22. Each bracket
includes a first wall portion 81 that rises from the anterior
support surface 21 near an edge 23 of the support member 16, and a
medially-extending portion 83 that is oriented toward the
medially-extending portion of the opposing bracket. FIG. 19B is a
rear perspective view of the laryngeal airway device coupled to the
introducer 11. FIG. 19C shows a front cross-sectional view of the
introducer 11 with the distal portion of the laryngeal airway
device 10 coupled to it; this view is along line C-C of FIG. 19B.
In this embodiment, the introducer 11 is identical in most respects
with the embodiment of the introducer illustrated in FIGS. 4-6, 7
and 9. The exception is in the structure of the track in the
embodiment illustrated in FIG. 19B. The track of the introducer 11
in FIG. 19B includes two opposing slide rails that are formed by
upwardly extending wall portions 47, which transition to
outwardly-extending sections 85. The outwardly-extending sections
85 of the track engage the medially-extending portions 83 of the
opposing brackets 80, permitting the laryngeal airway device to
engage and slidably move along the track from the proximal to the
distal end of the introducer 11. At the distal end of the
introducer, the widths of the outwardly-extending portions 85
reduce medially until only the upward extensions 47 remain, thereby
permitting the laryngeal airway device to disengage from the
introducer 11.
[0076] Many variations of the coupler/track combination are
possible. Not all are included in the embodiments that have been
illustrated and described. Possible alternate embodiments could
include a track with a single rail on the posterior side of the
introducer and a coupler on the sealing member that is adapted to
engage it.
[0077] The coupling and tracking features of this invention may
also be applied to laryngeal blade technology that is known in the
art, by applying a track to a blade. In this regard, FIGS. 20A-20D
show a laryngoscope 80 having a handle 82 and a curved blade 84
with a fiberoptic channel 85 disposed thereon. The handle 82 may be
conventionally detachably joined to the blade 84 by a mechanism
including elements 86a and 86b. The blade 84 preferably has the
shape of a capital "J" in a side elevation. The blade 84 includes
an anterior surface 88 and a posterior side 89. A track 96 is
formed on the posterior side 89. The track 96 is constructed in the
same manner as the track 46 on the introducer 11. So modified, the
blade 84 will have the form and function of the introducer that are
necessary for guiding or tracking. Therefore, a laryngeal airway
device 10 with a coupler 25 may be slidably coupled to the track 96
and guided thereby in the manner and for the purpose discussed
above. The track 96 is shown in cross-section in FIG. 20D with the
tab 26 of the flange 25 coupled thereto. Manifestly, the invention
therefore may be practiced using as an introducer a blade device
having a track formed thereon. It should be evident that the track
on the laryngeal blade device may have either embodiment discussed
above, and any equivalent thereof. Further, the distal end of the
blade 84 may be modified to accommodate the vallecular engagement
features discussed above.
[0078] Clearly, many other embodiments and modifications of this
invention will occur readily to those of ordinary skill in the art
in view of these teachings. Therefore, this invention is to be
limited only by following claims, which include all such
embodiments and modifications when viewed in conjunction with the
above specification and accompanying drawings.
* * * * *