The Proseal Laryngeal Mask Airway in Prone Patients: a Retrospective Audit of 245 Patients

The use of the classic laryngeal mask airway (classic LMA) in the prone position is controversial, but the ProSeal laryngeal mask airway (ProSeal LMA) may be more suitable as it forms a better seal and provides access to the stomach. In the following retrospective audit, we describe our experience with the insertion of and maintenance of anaesthesia with, the ProSeal LMA in 245 healthy adults in the prone position by experienced users. The technique involved (1) the patient adopting the prone position with the head to the side and the table tilted laterally; (2) pre-oxygenation to end-tidal oxygen >90%; (3) induction of anaesthesia with midazolam/alfentanil/propofol; (4) facemask ventilation (5) a single attempt at digital insertion and if unsuccessful a single attempt at laryngoscope-guided, gum elastic bougie-guided insertion; (6) gastric tube insertion; (7) maintenance of anaesthesia with sevoflurane/O/N2O; (8) volume controlled ventilation at 8-12 ml/kg; (9) emergence from anaesthesia in the supine position; and (10) removal ofthe ProSeal LMA when awake. Facemask ventilation was always successful. ProSealLMA insertion was successful in all patients: 237 with digital insertion and eight with bougie-guided insertion. Ventilation was successful in all patients. Gastric tube insertion was successful in all patients. Correctable partial airway obstruction occurred in three patients, but there was no hypoxia, hypercapnoea, displacement, regurgitation, gastric insufflation or airway reflex activation. Our findings suggest that the insertion of and maintenance of anaesthesia with the ProSeal LMA is feasible in the prone position by experienced users.