A prospective comparison of three heat preservation methods for patients undergoing hypothermic cardiopulmonary bypass

Objective: To prospectively compare 3 methods of body heat preservation in patients undergoing surgery requiring the use of hypothermic cardiopulmonar y bypass (CPB). Design: Prospective, randomized, and nonblinded. Setting: University teaching hospital. Participants: Adult cardiac surgery patients(n = 101). Interventions: Subjects were randomly assigned to 1 of 3 treatment groups: Group 1 (n = 33) used a fluid-filled warming blanket, group 2 (n = 31) used a heated and humidified breathing circuit, and group 3 (n = 37) used intra venous fluid warmers for the administration of all fluids. Treatments start ed on separation from CPB and concluded at the end of the intraoperative ex perience. Anesthetic technique, minute ventilation, conduct of CPB, and roo m temperature in the operating room were standardized. Measurements and Main Results: Blood temperature was measured at its nadir on CPB, on separation from CPB, and just before departure from the operatin g room. No differences were found among groups for CPB duration, coldest ve nous temperature on CPB, rewarming time, rate of rewarming, room temperatur e, or blood temperature on separation from CPB. There were no significant d ifferences found in post-CPB temperature afterdrop among groups. Conclusions: This study suggests that there is no statistically significant disparity in the effectiveness of these 3 intraoperative heat preservation methods. Ease of use and cost-effectiveness should guide the choice of war ming method post-CPB. Copyright (C) 2000 by W.B. Saunders Company.