['Resuming two lung ventilation (2LV) from one lung ventilation (OLV) has been proven to induce significant oxidative stress, mainly by superoxide release. Although total intravenous anesthesia and inhalational anesthesia are both used in thoracic surgery, different anesthetics may alter the oxidant/antioxidant balance.', 'Thirty patients undergoing thoracic surgery were randomly allocated to the propofol infusion (intravenous) group or isoflurane (inhalational) group after induction and placement of a double lumen endobronchial tube. Reactive oxygen species (ROS) production and total antioxidant status (TAS) were measured during OLV and 2LV manipulations. Blood samples were taken in the lateral position before OLV (T1), immediately before resuming 2LV (T2), and 5 minutes (T3) and 20 minutes (T4) after resuming 2LV, for measurement of ROS.', 'ROS production increased significantly at T3 and T4 in both groups but to a lesser extent in the propofol infusion group. TAS levels increased with time in the propofol group but not in the isoflurane group.'] Does propofol infusion shorten and attenuates oxidative stress during one lung ventilation?