 The LMA generally provides an adequate airway, but certain problems remain. 1 In 8-33 of LMA placements, more than one attempt is required. 2 It is sometimes difficult to advance the LMA without extending the neck which is contraindicated in some patients. 3 The device does not protect the airway from aspiration of gastric contents. 4 It does not provide an airtight seal around the larynx the usual pressures causing leakage of gas being 15-20 cm H20. Consequently, the device functions poorly during positive-pressure ventilation. 5 The esophagus is included within the rim of the LMA in 10-15 of patients, directly exposing the esophagus to positive airway pressures. This often results in insufflation of the stomach and postoperative discomfort. 