Gastro-Laryngeal Mask

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. The special provision also favors such collapse of the mask when deflated as to provide a leading flexible edge for piloting a safe and correct advancing insertional advance of the deflated mask in the patient's throat, in avoidance of epiglottis interference and to the point of locating engagement in the upper sphincter of the oesophagus.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This application is a continuation of and claims priority under 35 U.S.C. § 120 to U.S. patent application Ser. No. 09 / 803,452, now U.S. Pat. No. RE39938, filed on Mar. 8, 2001, entitled Gastro-Laryngeal Mask, the entire contents of which are incorporated herein by reference, which is a reissue of patent application Ser. No. 08 / 921,169, now U.S. Pat. No. 5,878,745, filed on Aug. 29, 1997, entitled Gastro-Laryngeal Mask, the entire contents of which are incorporated herein by reference, which is a continuation of and claims priority under 35 U.S.C. § 120 to U.S. patent application Ser. No. 08 / 609,521, filed on Mar. 1, 1996, entitled Gastro-Laryngeal Mask, now abandoned.BACKGROUND OF THE INVENTION[0002]This invention relates to a laryngeal-mask airway (LMA) device, which is an artificial airway device designed to facilitate lung ventilation in an unconscious patient by forming a low-pressure seal around the laryngeal inlet. An inflatable-ri...

AI Technical Summary

Benefits of technology

"The present invention provides an improved gastro-laryngeal mask that overcomes problems with previous designs. The mask has a construction that allows for easy compression and flexure of the gastric passage when the mask is inflated. The mask also ensures a flexible evacuation tube that can adapt to the patient's airway and safely remove gastric products. The inflated mask forms a wedge shape for proper insertion and ensures a maximally open evacuation passage. These technical effects are achieved through the use of two structural mechanisms that prevent lateral and antero-posterior compression of the evacuation tube."

Problems solved by technology

In practice, although a gastro-laryngeal-mask as described in said U.S. Pat. No. 5,355,879 works well, it has the disadvantage that the gastric evacuation channel needs to be sufficiently stiff to prevent its collapse under the influence of the increased pressure within the back-cushion cuff, when it is inflated in the pharynx.

A suitably stiff tube is readily provided, but the whole device is then more difficult to insert into the patient's throat, since insertion involves flexing the device around the angle at the back of the tongue.

Provision of a pre-curved airway tube facilitates passage around the back of the tongue, but the advancing distal tip end of the device is then more likely to collide with the glottis (or entrance to the larynx), and indeed it may block the larynx by so doing, with consequent danger to the patient.

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