Preoperative Patient Warming for Prevention of Perioperative Hypothermia in Major Abdominal Surgery

In the intervention groups a forced-air cover (Level 1 Snuggle Warm Upper Body Blanket, Smiths Medicals) will be positioned over the patients sitting or laying on the operating table for 15 min before start of epidural anaesthesia and afterwards till start of general anaesthesia (group 3), for 15 min before start of general anaesthesia (group 2) or only after induction of general anaesthesia (group 1, control). All patients will receive forced-air warming after induction of general anaesthesia till end of surgery.