Gastroesophageal reflux during anaesthesia.

While the number of patients at risk for vomiting and aspiration has been reported to be high, the incidence of clinically important pulmonary aspiration is low. We sought to define the incidence of gastroesophageal reflux (GER) and to correlate this with the clinical variables of obesity, history of oesophagitis, bucking and changes in body position. Continuous oesophageal pH measurement was used to determine the frequency of gastroesophageal reflux in 44 patients having general anaesthesia for elective surgical procedures. Acid reflux to a pH value of less than four occurred in seven patients (15.9%) during anaesthesia. This was associated temporally with straining on the endotracheal tube in six subjects (13.6%). We conclude that traditional risk factors are not always predictive of those patients at risk of regurgitation and aspiration.