Unintended Perioperative Hypothermia

Background: Hypothermia, defined as a core body temperature less than 36 degrees C (96.8 degrees F), is a relatively common occurrence in the unwarmed surgical patient. A mild degree of perioperative hypothermia can be associated with significant morbidity and mortality. A threefold increase in the frequency of surgical site infections is reported in colorectal surgery patients who experience perioperative hypothermia. As part of the Surgical Care Improvement Project, guidelines aim to decrease the incidence of this complication. Methods: We review the physiology of temperature regulation, mechanisms of hypothermia, effects of anesthetics on thermoregulation, and consequences of hypothermia and summarize recent recommendations for maintaining perioperative normothermia. Results: Evidence suggests that prewarming for a minimum of 30 minutes may reduce the risk of subsequent hypothermia. Conclusions: Monitoring of body temperature and avoidance of unintended perioperative hypothermia through active and passive warming measures are the keys to preventing its complications.