The Use of Proseal Laryngeal Mask Airway in Caesarean Section--Experience in 3000 Cases (Report‪)‬

Rapid sequence induction is currently the recommended technique for general anaesthesia for caesarean section (1). In addition to using a pre-calculated dose of intravenous anaesthetic plus a rapid-acting muscle relaxant, this technique requires direct laryngoscopy and tracheal intubation while cricoid pressure is applied (2). One of the greatest concerns with this approach is the known high incidence of difficult laryngoscopy and failed intubation in a group of patients who are also at risk of rapidly developing hypoxaemia (3). Indeed, maternal death due to a failure to oxygenate was noted to increase when rapid sequence induction was first introduced into clinical practice (4). Although now a part of established practice, the evidence supporting the insertion of an endotracheal tube with the use of cricoid pressure to decrease aspiration is questionable (5). One of the advantages cited for placing an endotracheal tube is to prevent the aspiration of regurgitated stomach contents into the trachea. Apart from casting doubt on the usefulness of cricoid pressure, a recent case series demonstrated that the routine use of the endotracheal tube did not reduce maternal death due to aspiration6. The authors also suggested the potential value of a gastric tube instead, to prevent regurgitation and aspiration. Moreover, in the elective setting, the risk of regurgitation and aspiration during anaesthesia is difficult to estimate--gastric emptying and stomach volumes have not been shown to be affected by pregnancy in non-labouring women (7), but the reduction of lower oesophageal sphincter pressure and thus barrier pressure to reflux during pregnancy, especially in an obese patient, potentially increases the risk of regurgitation (8,9).