Perioperative maintenance of normothermia reduces the incidence of morbid cardiac events. A randomized clinical trial

JAMA. 1997 Apr 9;277(14):1127-34.


Objective: To assess the relationship between body temperature and cardiac morbidity during the perioperative period.

Design: Randomized controlled trial comparing routine thermal care (hypothermic group) to additional supplemental warming care (normothermic group).

Setting: Operating rooms and surgical intensive care unit at an academic medical center.

Subjects: Three hundred patients undergoing abdominal, thoracic, or vascular surgical procedures who either had documented coronary artery disease or were at high risk for coronary disease.

Outcome measure: The relative risk of a morbid cardiac event (unstable angina/ischemia, cardiac arrest, or myocardial infarction) according to thermal treatment. Cardiac outcomes were assessed in a double-blind fashion.

Results: Mean core temperature after surgery was lower in the hypothermic group (35.4+/-0.1 degrees C) than in the normothermic group (36.7+/-0.1 degrees C) (P<.001) and remained lower during the early postoperative period. Perioperative morbid cardiac events occurred less frequently in the normothermic group than in the hypothermic group (1.4% vs 6.3%; P=.02). Hypothermia was an independent predictor of morbid cardiac events by multivariate analysis (relative risk, 2.2; 95% confidence interval, 1.1-4.7; P=.04), indicating a 55% reduction in risk when normothermia was maintained. Postoperative ventricular tachycardia also occurred less frequently in the normothermic group than in the hypothermic group (2.4% vs 7.9%; P=.04).

Conclusion: In patients with cardiac risk factors who are undergoing noncardiac surgery, the perioperative maintenance of normothermia is associated with a reduced incidence of morbid cardiac events and ventricular tachycardia.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Aged
  • Analysis of Variance
  • Anesthesia
  • Baltimore
  • Body Temperature*
  • Coronary Disease / complications*
  • Coronary Disease / epidemiology
  • Electrocardiography
  • Female
  • Heart Arrest* / epidemiology
  • Heart Arrest* / etiology
  • Heart Arrest* / prevention & control
  • Hemodynamics
  • Hospitals, University
  • Humans
  • Hypothermia
  • Incidence
  • Intraoperative Period
  • Male
  • Middle Aged
  • Monitoring, Physiologic
  • Multivariate Analysis
  • Myocardial Ischemia* / epidemiology
  • Myocardial Ischemia* / etiology
  • Myocardial Ischemia* / prevention & control
  • Postoperative Complications / epidemiology
  • Postoperative Complications / prevention & control*
  • Postoperative Period
  • Prospective Studies
  • Regression Analysis
  • Risk Factors
  • Surgical Procedures, Operative*