Comparison of regional cerebral oxygen saturation during one-lung ventilation under desflurane or propofol anesthesia: A randomized trial

During one-lung ventilation (OLV), deterioration of pulmonary oxygenation reduces arterial oxygen saturation and cerebral oxygen saturation (rSO(2)). However, oxidative stress during OLV causes lung injury, so the fraction of inspiratory oxygen (FiO(2)) should be kept as low as possible. We investigated the changes in rSO(2) under propofol or desflurane anesthesia while percutaneous oxygen saturation (SpO(2)) was kept as low as possible during OLV. METHODS: Thirty-six patients scheduled for thoracic surgery under OLV in the lateral decubitus position were randomly assigned to propofol (n = 19) or desflurane (n = 17) anesthesia. FiO(2) was set to 0.4 at the start of surgery under two-lung ventilation (measurement point: T3) and then adjusted to maintain an SpO(2) of 92% to 94% after the initiation of OLV. The primary outcome was the difference in the absolute value of the decrease in rSO(2) from T3 to 30 minutes after the initiation of OLV (T5), which was analyzed by an analysis of covariance adjusted for the rSO(2) value at T3. RESULTS: The mean rSO(2) values were 61.5% ± 5.1% at T3 and 57.1% ± 5.3% at T5 in the propofol group and 62.2% ± 6.0% at T3 and 58.6% ± 5.3% at T5 in the desflurane group. The difference in the absolute value of decrease between groups (propofol group − desflurane group) was 0.95 (95% confidence interval, [−0.32, 2.2]; P = .152). CONCLUSIONS: Both propofol and desflurane anesthesia maintain comparable cerebral oxygenation and can be used safely, even when the SpO(2) is kept as low as possible during OLV.