REQUIREMENTS FOR TARGET-CONTROLLED INFUSION OF PROPOFOL TO INSERT THELARYNGEAL MASK AIRWAY

The success rate for insertion of the laryngeal mask airway was assess ed in 60 patients using a target-controlled infusion of propofol. Elev en of 15 patients who received a target propofol concentration of 5 mu g.ml(-1) had the laryngeal mask inserted successfully within 3 min of induction of anaesthesia. Fourteen of 15 patients who received 6 mu g .ml(-1) had successful insertion within 3 min and all 15 patients who received 7 mu g.ml(-1) had successful insertion within 3 min. Patients who received 8 mu g.ml(-1) had successful insertion within 90 s of in duction of anaesthesia. The increased success rate of LMA insertion wi th the higher target propofol concentrations was achieved without majo r haemodynamic effects in this group of fit patients. However, adverse cardiovascular effects may occur with these doses in elderly or unfit patients. It is important ill individual patients to titrate the targ et propofol concentration to achieve the required clinical end-point.