Randomized clinical trial of perioperative systemic warming in major elective abdominal surgery

Background: Hypothermia is common in the operating theatre and may increase susceptibility to postoperative complications. Intraoperative systemic warming has been shown to improve outcomes of surgery. This study aimed to examine the effects of additional perioperative systemic warming on postoperative morbidity. Methods. All patients admitted for elective major abdominal surgery and fulfilling the inclusion criteria were randomized into control or warming groups. Both groups were warmed during surgery, but patients in the warming group were additionally warmed 2 h before and after surgery using a conductive carbon polymer mattress. Results: The trial recruited 103 patients (56 in the control group, 47 in the warming group). Both groups were well matched for age, sex and clinical state. Patients in the warming group had lower blood loss (median 200 (range 5-1000) ml versus median 400 (range 50-2300) ml in the control group; P = 0.011) and complication rates (15 (32 per cent) of 47 versus 30 (54 per cent) of 56 in the control group; P = 0.027). There were three deaths; two in die control group (P = 0.566). Conclusion: Extending systemic warming to the perioperative period had additional beneficial effects, with minimal additional cost and patient discomfort.