Conditions for insertion of the laryngeal mask airway: comparisons between sevoflurane and propofol using fentanyl as a co-induction agent. A pilot study

Background and objective: To compare the conditions for insertion of the laryngeal mask airway using sevoflurane or propofol plus fentanyl. We evaluated the haemodynamic changes and cost of induction of anaesthesia in both groups. Methods: Sixty patients were equally and randomly divided into two groups. Both groups received fentanyl 1 mug kg(-1). Patients in the sevoflurane group were induced with 8% sevoflurane and those in the propofol group with propofol 2.5 mg kg(-1). Conditions for insertion were graded on a three-point scale using six variables. Overall, conditions were assessed as excellent, satisfactory or poor based on the total score in each group. Systolic and diastolic arterial pressure and heart rate were recorded for 6 min after mask insertion. The financial cost of induction in both groups was calculated. Results: The mean (+/-SD) time taken from induction to successful laryngeal mask insertion was significantly shorter with propofol (68.70 +/- 22.60 s) compared with sevoflurane (149.83 +/- 55.25 s). Excellent or satisfactory conditions were observed in 30 (100%) patients in the propofol group and in 29 (96.66%) in the sevoflurane group. Systolic and diastolic arterial pressures were significantly lower in the propofol group. The cost of sevoflurane used was E3.95 +/- 1.48 (Rs 216.23 +/- 64.66) (P < 0.05) compared with that of propofol, which was E3.23 +/- 0.65 (Rs 141.00 +/- 28.20). Conclusions: Although there was a faster induction with propofol-fentanyl, conditions for insertion of the laryngeal mask airway were similar in both groups. Haemodynamic stability was better with sevoflurane-fentanyl. The propofol-fentanyl combination was more cost-effective.