Extracorporeal venovenous recirculation for the treatment of hypothermia during elective aortic surgery: a phase I study.

Abstract

Hypothermia caused by massive transfusion or prolonged exposure during operation is difficult to reverse and is associated with adverse side effects. This prospective, randomized study evaluated a technique using extracorporeal venovenous recirculation (EVR) through a roller pump-driven device with a commercial countercurrent heat exchanger used for treatment of hypothermia (temperature < 35.5 degrees C) occurring during elective aortic operation. Patients undergoing aortic operation had routine prophylaxis against hypothermia including ventilator cascades, warming blankets, and low-velocity fluid warmers. When core temperature was less than 35.5 degrees C, patients were randomized to continue existing therapy (control, n = 7) or EVR (n = 8), performed through two large-bore venous lines. There were no differences in age, sex, weight, body surface area, Acute Physiology and Chronic Health Evaluation II score, fluid replacement, length of operation, blood lost or given, induction temperature, red blood cell or platelet structure, hemolysis, length of intensive care unit or hospital stay, complications, or mortality rates. EVR was associated with increased final core temperature (35.5 degrees +/- 0.8 degrees [EVR] vs 33.8 degrees +/- 0.9 degrees [control]; p < 0.005) and body heat content (-13.9 +/- 62.3 kcal [EVR] vs -118.2 +/- 62.2 kcal [control]; p < 0.01), with heat gained being proportional to flow rate. These data show that EVR provides a safe and effective method for the treatment of hypothermia.