Airway Maintenance

The laryngeal mask airway (LMA), commonly used in the operating theatre, is increasingly being used by hospitals for the management of cardiorespiratory arrest and in recovery following surgery. The literature relating to the LMA has correspond­ ingly grown in recent years, helping to define its uses, merits and disadvantages. A survey from 1983-1991 reveals a total of 183 publications on the LMA and over 70 per cent of these were in UK journals (Brimacombe and Shorney 1993). As of August 1996, there are estimated to be nearly 1,000 publications worldwide on the LMA (Personal communication 1996). As a result of this increased use, recovery staff and ward nurses involved in airway management need to know how to manage patients with an LMA in place (Brain 1993, Brimacombe 1993). silicone compounds and incorporates a polysulfone connector and a polypropylene valve (Intavent 1993). The current design is available in six sizes. The appropriate size is determined by the patient’s weight and, after insertion, inflated with the appropriate volume of air (Table 1) (O'Meara 1995). The shaft of the LMA is available with the tradi­ tional wide bore lumen or a narrower non-kinking design which is reinforced with a metal spiral. It can withstand repeated autoclaving, however, the manu­ facturer recommends that each LMA be used no more than 40 times (Intavent 1993). A new prototype LMA is currently being evaluated. The key design features are that it incorporates a second mask to isolate the upper oesophagus and a second dorsal cuff to increase the seal against the glottis (Brain etal 1995).