Preconditioning of One-lung Ventilation

"The patient undergoing thoracic surgery is intubated with double lumen tube after induction of general anesthesia with propofol and remifentanil.~In the intervention group, 5 cycles of one-lung ventilation preconditioning (2-min of one-lung ventilation and 2-min of two-lung ventilation for 1 cycle) is performed before surgical incision. One-lung ventilation is done at dependent lung with FiO2 100% and tidal volume 6 ml kg-1. Two-lung ventilation is done with FiO2 50%, tidal volume 8 ml kg-1."