The LMA 'ProSeal'--a laryngeal mask with an oesophageal vent.

We describe a new laryngeal mask airway (LMA) that incorporates a second tube placed lateral to the airway tube and ending at the tip of the mask. The second tube is intended to separate the alimentary and respiratory tracts. It should permit access to or escape of fluids from the stomach and reduce the risks of gastric insufflation and pulmonary aspiration. It can also determine the correct positioning of the mask. A second posterior cuff is fitted to improve the seal. A preliminary crossover comparison with the standard mask in 30 adult female patients showed no differences in insertion, trauma or quality of airway. At 60 cm H2O intracuff pressure, the new LMA gave twice the seal pressure of the standard device (P < 0.0001) and permitted blind insertion of a gastric tube in all cases. It is concluded that the new device merits further study.