Object: Evaluating the consumption of sevofluran during low flow anesthesia with ecoflow at fresh gas flow 0.5 or 1 L/min for abdominal surgery in elderly patients.

Materials and methods: 74 ASA grade 1, 2 and 3 patients, aged ≥ 60 years undergoing abdominal surgery under general anesthesia with an endotracheal tube were included. After induction the volatile anesthetic (SEV) was opened at 3% and the flow of 6 L/min until entropy < 60 then reduced to 0,5 L/min for group N0.5 and 1 L/min for group 1 L/min. Ventilation: VCV, Vt = 8 ml/kg, RR = 10, PEEP = 5 cmH₂O. Consumption of sevofluran, MAC-Sevofluran, entropy, SPI, TOF, heart rate, MAP were recorded.

Results and conclusions: Mean sevoflurane consumption was significantly lower in Group N0.5 compared to Group N1 (0.14 ± 0.03 ml/min, 0.19 ± 0.05 ml/min; p-value < 0.001). So the use of low flow 0.5 L/min was associated with decrease in the cost of anaesthetic and environmental pollution.