Background. This study aimed to evaluate and compare total cost of sevoflurane and propofol for 1.0 MAC-hour of anaesthesia, employing three anaesthetic techniques. Methods. Adult patients scheduled for surgical procedures under general anaesthesia anticipated to last approximately an hour were randomized into three groups ( each), to receive anaesthesia using one of the following techniques: low flow technique involving induction with propofol, followed by sevoflurane delivered using initial fresh gas flows of 6？L/min till MAC reached 1.0 and then reduced to 0.5？L/min; alternate method of low flow entailing only a difference in fresh gas flow rates being maintained at 1？L/min throughout; the third technique involving use of sevoflurane for both induction and maintenance of anaesthesia. Results. Cost of sevoflurane to maintain 1 MAC-hour of anaesthesia was clinically least with low flow anaesthesia, though statistically similar amongst the three techniques. Once the cost of propofol used for induction in two of the three groups was added to that of sevoflurane, cost incurred was least with the technique using sevoflurane both for induction and maintenance of anaesthesia, as compared to low flow and alternative low flow techniques, a 26% and 32% cost saving, respectively (). 1. Introduction Newer inhalational agents such as sevoflurane offer several advantages over older agents but are comparatively more expensive. Evolving economic constraints across the world have brought forth the need to develop techniques that can minimize the cost of anaesthesia [1]. The technique of low flow anaesthesia (LFA) employing reduced fresh gas flow rates is known to decrease the consumption of inhalational agents such as sevoflurane and hence the cost of anaesthesia [2–5]. An “alternative method” of LFA has also been suggested to minimize the consumption of inhalational agent [6]. Herein reduced fresh gas flow rates are used right from the beginning and continued till the end of the anaesthetic procedure. This is in contrast to usual practice of LFA wherein fresh gas flow rates are reduced only after an initial period of higher flows [7]. However, this “alternative method of LFA” has not been evaluated when using sevoflurane as the inhalational agent. In yet another anaesthetic technique, involving use of inhalational volatile agent for induction as well as maintenance of anaesthesia (VIMA) decreased cost is reported as compared to an intravenous induction followed by inhalational maintenance or continued use of the intravenous agent [8–10]. Thus, although these three
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