UPTAKE OF DESFLURANE DURING ANESTHESIA

The amount of desflurane required to maintain an end-expired concentra tion of 8% was measured in 30 ASA 1 and 2 patients undergoing elective spinal surgery. The anaesthetic was administered using a computer-con trolled closed circle system. After an initial period during which the expired concentration of desflurane was stabilised (4 min) the rate o f uptake showed a bi-exponential decline. Mean cumulative usage of des flurane was 10.1 ml of liquid at 30 min, 14.8 ml at 60 min, 25.4 ml at 120 min, 35.8 at 180 min.