Monitoring and control for laryngeal mask airway device.

A reversibly operable motor is mechanically connected to automatically position die piston (27) of an air syringe (26) that is pneumatically connected to the inflatable/deflatable seal ring or cuff (19) of a laryngeal mask airway device (LMA) (12) that is installed in a patient, who is being ventilated and/or anaesthetized via the airway of the LMA device (12). Ideally, (i) die air at die head end of die syringe (26), plus (ii) the air contained in the inflatable cuff (19) of die LMA (12), plus (iii) die air contained in their interconnection, is a "substantially constant" volume which is shared at these three locations but which is automatically shifted by piston (27) 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. Various instrumentalities (10), including microprocessor-controlled instrumentalities, continuously monitor patterns of system response to observed pattern abnormality, with audibly and visually reported warnings to die anesthetists.