Abstract: An artificial airway device for use in unconscious patients comprises a laryngo-pharyngeal mask including a roughly elliptical shape, expandable masking ring. The expandable mask sealingly surrounding the laryngeal inlet when expanded to obstruct communication between the laryngeal inlet and oesophagus. One or more airway tubes connected to the mask provide for fluid flow to a portion of the mask facing the laryngeal inlet when said mask sealingly surrounds the laryngeal inlet. A gastro-tube connected to the mask is bonded along most of its length to the airway tube(s) and provides a fluid flow-path to the surface of said mask facing the oesophagus when said mask sealingly surrounds the laryngeal inlet. The cross-section area of said gastro-tube is at least as great as that of the airway tube.

Abstract: The disclosed method for fabricating low cost laryngeal mask devices includes providing a mold, the mold including interior walls that define a hollow interior volume. The interior volume includes a first portion and a second portion. A liquid plastic material is introduced into the mold, and then the mold is moved so as to coat the mold's interior walls. The liquid plastic material and then allowed to cure. The cured plastic material is then removed from the mold and the cured plastic material includes a generally elliptically shaped plate and a cuff. The cuff is formed from plastic material that coated the portion of the interior walls that defined the first portion. The plate defines a laryngeal side, a pharyngeal side, and a central aperture. An interior perimeter of the cuff is attached to the laryngeal side of the plate proximal to a perimeter of the central aperture. An outer perimeter of the cuff is attached to the laryngeal side of the plate proximal to an outer perimeter of the plate.

Abstract: In its presently preferred form, an endotracheal tube (ET) is shaped to bring its rounded or bevelled distal tip end into the central axis or midline, for ease of passage into the glottic opening and through the region of the vocal cords; the distal-end shaping also involves a laterally and vertically reducing taper that is symmetrical with respect to a vertical plane of symmetry which includes the central axis. Distal-end ports or perforations are in the symmetrically arrayed walls of a triangular section of the tube which at least characterizes the region of tapering section and which conforms with the triangular-shaped space between the vocal cords, for added ease of insertion into the patient's trachea. The reducing taper of the roughly triangular-shaped section extends preferably and optionally to form a wedging fit against vocal cords, with or without the assistance of a conventional inflatable cuff of similar sectional profile.

Abstract: An artificial airway device for use in unconscious patients comprises a laryngo-pharyngeal mask including a roughly elliptical shape, expandable masking ring. The expandable mask sealingly surrounding the laryngeal inlet when expanded to obstruct communication between the laryngeal inlet and oesophagus. One or more airway tubes connected to the mask provide for fluid flow to a portion of the mask facing the laryngeal inlet when said mask sealingly surrounds the laryngeal inlet. A gastro-tube connected to the mask is bonded along most of its length to the airway tube(s) and provides a fluid flow-path to the surface of said mask facing the oesophagus when said mask sealingly surrounds the laryngeal inlet. The cross-section area of said gastro-tube is at least as great as that of the airway tube.

Abstract: The disclosed method of monitoring the cuff pressure of an LMA provides an estimation of a patient's anesthetic state. Cuff pressure tends to rise and fall during IPPV and spontaneous breathing. One of the disclosed methods activates an alarm if an instantaneous value of the cuff pressure exceeds selected levels. This method may also automatically adjust the selected levels. One of the disclosed methods activates an alarm if activity of the cuff pressure as observed over a period of time exceeds a selected level.

Abstract: The disclosed endotracheal tube includes a silicone tubular member that has a proximal end, a distal end, and a lumen extending through the member to supply air from the proximal end to the distal end. The tubular member defines a first zone and a second zone. At least a portion of the first zone has a first outer diameter. The second zone has a second outer diameter. The first outer diameter is less than the second outer diameter. The first and second zones are adjacent to one another and are configured for insertion into the trachea of a human patient. A silicon cuff is attached to the tubular member such that the cuff extends over at least a portion of the first zone. The silicone cuff is mounted such that when the cuff is inflated in a trachea, the cuff reaches its plateau pressure prior to circumferentially contacting the inner wall of the trachea so that an accurate pressure reading may be taken of the pressure the cuff exerts on an inner wall of the trachea.

Abstract: A reversibly operable motor is mechanically connected to automatically position the piston of an air syringe that is pneumatically connected to the inflatable/deflatable seal ring or cuff of a laryngeal mask airway device (LMA) that is installed in a patient, who is being ventilated and/or anaesthetized via the airway of the LMA device. Ideally, (i) the air at the head end of the syringe, plus (ii) the air contained in the inflatable cuff of the LMA, plus (iii) the air contained in their interconnection, is a “substantially constant” volume which is shared at these three locations but which is automatically shifted by piston displacement, such that air pressure in the substantially constant volume is caused to correct as necessary for conformance to a predetermined level of set-point pressure.

Abstract: The disclosed laryngeal mask airway device includes a mask portion and an airway tube. The mask portion includes an inflatable cuff, which defines a central opening when the cuff is inflated. The airway tube defines an internal passage extending from a proximal end of the tube to a distal end of the tube. The airway tube further defines two or more tabs disposed near the distal end of the tube. The mask portion is coupled to the airway tube near the distal end of the airway tube, and the tabs extend from the airway tube into the central opening defined by the cuff when the cuff is inflated.

Abstract: In its presently preferred form, an endotracheal tube (ET) is shaped to bring its rounded or bevelled distal tip end into the central axis or midline, for ease of passage into the glottic opening and through the region of the vocal cords; the distal-end shaping also involves a laterally and vertically reducing taper that is symmetrical with respect to a vertical plane of symmetry which includes the central axis. Distal-end ports or perforations are in the symmetrically arrayed walls of a triangular section of the tube which at least characterizes the region of tapering section and which conforms with the triangular-shaped space between the vocal cords, for added ease of insertion into the patient's trachea. The reducing taper of the roughly triangular-shaped section extends preferably and optionally to form a wedging fit against vocal cords, with or without the assistance of a conventional inflatable cuff of similar sectional profile.

Abstract: In its presently preferred form, an endotracheal tube (ET) is shaped to bring its rounded or bevelled distal tip end into the central axis or midline, for ease of passage into the glottic opening and through the region of the vocal cords; the distal-end shaping also involves a laterally and vertically reducing taper that is symmetrical with respect to a vertical plane of symmetry which includes the central axis. Distal-end ports or perforations are in the symmetrically arrayed walls of a triangular section of the tube which at least characterizes the region of tapering section and which conforms with the triangular-shaped space between the vocal cords, for added ease of insertion into the patient's trachea. The reducing taper of the roughly triangular-shaped section extends preferably and optionally to form a wedging fit against vocal cords, with or without the assistance of a conventional inflatable cuff of similar sectional profile.

Abstract: A gastro-laryngeal mask features softly compliant construction of the distal half of the mask, wherein the mask is of generally elliptical configuration, with an inflatable peripheral cuff to seal and support the mask around the laryngeal inlet. A back cushion is inflatable to engage the back wall of the pharynx and thus to forwardly load the peripheral-cuff seal to the laryngeal inlet. An evacuation tube for external removal of a possible gastric discharge completes an evacuation or discharge passage contained within the mask and opening through the distal end of the peripheral cuff. Special provision is made for assuring integrity of the discharge passage within the flexible distal half of the mask, i.e., assuring against collapse of the distal-end half of the softly compliant evacuation tube in the distal region of the mask, such that inflation of the mask does not compromise viability of the evacuation tube by compressing softly compliant material of the evacuation tube during periods of mask inflation.

Abstract: A laryngeal-mark airway device has additional provision for extraction of gastric discharges while the mask seals the airway to the laryngeal inlet. A single elongate flexible small-bore drainage tube is so bonded to the posterior curvature of an elongate flexible airway as to enhance torsional stiffness in the combined airway tube and drainage tube. The airway tube has a customary fit to the air inlet of the domed backing plate of the mask, and a generally elliptical inflatable ring around the backing plate and lumen of the mask is configured to establish a continuous peripherally sealed engagement to the laryngeal inlet. The elongate flexible drainage tube has sealed entry into the distal end of the inflatable ring, distally traversing the same with sealed distal exit from the distal end of the inflatable ring.

Abstract: An airway device in the form of a modified laryngeal mask is fitted with single, multiple or paired electrodes (herein termed "internal electrodes") so placed as to enable stimulation of or to record a spontaneous degree of activity of selected excitable tissues (a) lying in direct contact with or in close proximity with the mask, or (b) in conjunction with suitably placed body-surface electrodes (herein termed "external electrodes") at one or more body-surface regions known to have muscular, neuro-muscular or other conductive relationship with organs more remoted situated from the mask, such internal electrodes being adapted for flexible connection to external monitoring or stimulating apparatus for diagnostic, therapeutic, palliative or sedative purposes.

Abstract: A manufacturing process to produce a laryngeal mask substantially as described in UK Patent GB2205499B consists in a mould which manufactures the inflatable annular ring formation of the device in an inverted form. This allows a more rigid core in the cavity mould or alternatively a dip-moulding process, which in turn, permits greater accuracy in control of wall thickness. An alternative form of the mould eliminates the need to assemble a further component, by incorporating the latter into the same single moulding process. And in a further alternative embodiment, the same single moulding process additionally provides an integrally formed inlet for oesophagus drainage, independent of the larynx-venting function of the mask per se.

Abstract: A shell of flexibly pliant material is in peripherally sealed engagement with the inflatable ring portion of a laryngeal mask such that when both the mask ring and the space within the shell are inflated, i.e., after patient installation of the mask in deflated condition, a back cushion is established with large-area self-adapting conformation to the back wall of the pharynx, so that inflation pressure in the back cushion not only positions back contours of the mask per se at offset from the back wall of the pharynx but in addition establishes a large area of uniformly distributed forward pressure on the mask per se, resulting in a pneumatically loaded application of the inflatable ring of the mask, into enhanced sealing conformance to and engagement with the laryngeal inlet.

Abstract: A manufacturing process to produce a laryngeal mask substantially as described in UK Patent GB2205499B consists in a mould which manufactures the inflatable annular ring formation of the device in an inverted form. This allows a more rigid core in the cavity mould or alternatively a dip-moulding process, which in turn permits greater accuracy in control of wall thickness. An alternative form of the mould eliminates the need to assemble a further component, by incorporating the latter into the same single moulding process. And in a further alternative embodiment, the same single moulding process additionally provides an integrally formed inlet for oesophagus drainage, independent of the larynx-venting function of the mask per se.

Abstract: An artificial airway device to facilitate lung ventilation in an unconscious patient comprises a rigid airway tube (10), which is curved to follow the airway of the patient, opening into the interior space or lumen of a mask portion (12) whose periphery (14) is adapted to seal around the inlet (36) to the larynx (38), and a rigid handle (9) mounted at the outer end of the airway tube (10) and curved away from the mouth of the airway tube (10).

Abstract: A laryngeal mask has an inflatable ring configured, upon inflation, to establish a peripheral seal around a patient's laryngeal inlet. Installation (insertion) is made in the fully deflated state, wherein the structural relation between the body of the mask and the inflatable ring is such that deflated ring surfaces become tightly opposed to each other so as to form a thin flange which peripherally surrounds the body of the mask and is concave on the posterior side of the mask; the concave flange effectively displaces all ring material away from the aperture of the mask, in the manner of the upturned brim of a hat. The concave flange is softly yieldable in its confinement by local body structures encountered in the course of mask insertion.

Abstract: A reflectance oximeter is so mounted to the upstream or proximal side of a laryngeal mask as to face the posterior wall of the pharynx when the laryngeal mask has been positioned to perform its function of sealed, exclusive airway communication with the laryngeal inlet. Thus positioned, radiation from the oximeter can utilize local back-bone features as a reflector, for two-way passage of the radiation through tissue which characterizes the posterior wall of the pharynx. Moreover, the oximeter-observation region is within the body, so that ambient light has no degrading effect, and changes in oxygen saturation will be detected earlier than by use of any peripherally placed oximeter probe.

Abstract: A clamping mechanism for use in conjunction with or forming an integral part of a laryngeal mask airway, for the purpose of forming a seal between the mask and the entrance to the larynx; the seal is sufficient to overcome the danger of aspiration of regurgitated or vomited matter into the lungs.