Reflux during positive pressure ventilation through the laryngeal mask.

Patients undergoing anaesthesia for cataract surgery were anaesthetized and their lungs ventilated by intermittent positive pressure ventilation. In one group, ventilation was facilitated by tracheal intubation and in the other group by laryngeal mask airway (LMA). Reflux of stomach contents into the oesophagus was monitored continuously using an indwelling oesophageal pH electrode. The number of discrete episodes of reflux was higher in the LMA group (P = 0.0178), as was the incidence of reflux at antagonism of neuromuscular block (P = 0.0349).