A Comparison Of Propofol Versus Sevoflurane For Laryngeal Mask Airway Insertion.

Abstract

IV Propofol is widely used for providing anaesthesia for LMA insertion. Sevoflurane is a new volatile anaesthetic with rapid induction and recovery characteristics. A randomized, double blinded trial was conducted to compare conditions for LMA insertion after induction of anaesthesia with either inhalation of Sevoflurane or intravenous Propofol in fifty ASA grade I or II female patients, who were randomly divided into two groups (n=25 in each group). Group P received IV Propofol. In Group S, after priming the Magills circuit with Sevoflurane 8% in N2O 50% and O2 (flow rate – 8 litres / minute) for 30 seconds, patients were asked to take vital capacity breaths via the face mask connected to the primed circuit. After the loss of eye lash reflex, which was considered as the end point of induction, the LMA insertion was attempted by an anaesthesiologist blinded to the induction technique. Scoring systems were used to grade the conditions for insertion and Fibreoptic bronchoscope position of the LMA. Induction was more rapid with IV Propofol. Excellent conditions for the LMA insertion were obtained in a significantly greater number of patients in Group P (64%) than in Group S (32%) (p=0.02). The mean score for conditions for LMA insertion was significantly better in Group P (p=0.012). 72% patients in Group P had full jaw opening when compared to 44% patients in Group S (p=0.047). Hence, it can be concluded that Propofol is better than Sevoflurane for LMA insertion using the loss of eye lash reflex as the end point of induction probably due to the better jaw relaxation