During surgery, intravenous crystalloids (Ringer-lactate solution) will be infused at a rate of 2-3 ml/kg/h and blood losses will be compensated with colloids (poly(0-2-hydroxy-ethyl)amidon, HAES 6%) and with red blood cell concentrates if the hemoglobin levels decreased below 80-90 g/L. At the end of surgery, all patients will be extubated in the operating theater after reversing the residual neuromuscular blockade with anticholinesterase agents. An active physiotherapy program including incentive spirometry, deep diaphragmatic breathing exercises and mobilization will be started in the high-dependency care unit (HDU). A maximal fluid balance of 500 ml per day will be targeted during the first 48 hours after surgery, by limiting fluid intakes including i.v. crystalloids (glucose-saline 0.45% 1 ml/kg/h), i.v. colloids (1/1 compensation of fluid losses through thoracic drains and oral beverages (500 ml on the day of surgery and 1’000-1’200 ml over the next two days).