A comparison of low and high flow desflurane anaesthesia in children

Objective: Low-flow anaesthesia has become increasingly common by using modern anaesthesia devices. We aimed to compare anaesthesia with low flow and high fresh gas flows in children. Methods: Forty children in the ASA I-II groups, aged 5-15 years who were operated for upper and lower extremities and operation times between two and four hours, were included in this study. During the operation, 4-6% desflurane, 2 L min^-1 N₂O and 2 L min^-1 O₂ were given to the low dose group throughout the first 10 minutes (n=20). Afterwards, 50% O₂, 50% N₂O, 4-6% desflurane were given as one MAC. In the high flow group (n=20) 4-6% desflurane, 2 L min^-1 N₂O and 2 L min^-1 O₂ were given throughout the operation. Inspiratory and expiratory concentrations of O₂, CO₂, N₂O and desflurane, vital parameters, BIS and MAC were measured. During the anaesthesia period, extubation period, and 24 hours after surgery arterial blood gas samples were taken. Results: Desflurane amount was 235±97 mL in the high flow group, and 106±26 mL in the low flow group. Although there were significant differences between the two groups in terms of inspired and expired O₂, CO₂, desflurane concentrations, and MAC levels, they were within clinically acceptable ranges. There was clinically no difference between the two groups. Lactate levels were higher in the low flow group (T1-T8 periods). There were no differences between the two groups in peroperative and recovery hemodynamics, arterial blood gas parameters, liver and kidney function, postoperative recovery period (extubation and orientation time). Conclusion: Our results show that low-flow anaesthesia, with the use of appropriate techniques and devices, close monitoring of blood gases and lactate levels, can be applied safely in children.