A 'restrictive' intraoperative fluid regimen, avoiding hypovolaemia but limiting infusion to the minimum necessary reduced major complications after complex surgery. This restrictive fluid regimen is especially relevant in thoracic surgery since acute lung injury is known to be related to large amount of fluid administration during operation to treat hypotension. One study suggests that, for every 500-mL increase in perioperative fluids, there is an odds ratio of 1.17 for developing ALI after lung resection. Slinger suggested that fluid should be restricted just to the point of maintaining urine output of 0.5 mL/kg/h, and vasopressors may be used if tissue perfusion is inadequate. Therefore, restriction of fluid administration and treatment of hypotension which is not caused by major hemorrhage with vasoactive agents could be a basic concept in thoracic anesthesia.