Inadvertent intraoperative hypothermia

Inadvertent perioperative hypothermia complicates a large percentage of surgical procedures and is related to multiple factors. Strictly regulated in normal conditions (+/- 0.2 degrees C), the core body temperature of an anaesthetised patient may fall by as much as 6 degrees C, while a 2 degrees C decrease is very common. This is due to a combination of anaesthesia-related impairment of the central thermoregulatory control and a cool operating room temperature, which, when superimposed on insufficient insulation and a failure to actively warm the patient, may result in profound temperature disturbances. As a result, prolonged wound healing, increased risk of wound infection, a higher rate of cardiac morbidity, and greater intraoperative blood loss and postoperative blood transfusion requirements may occur. The reasons for this are said to include underlying changes in microcirculation, coagulation, immunology and an increase in the duration of action of most anaesthesia medications. As effective methods have been available for a number of years now, it is currently indicated to maintain intraoperative normothermia in order to minimise procedure-related risk and improve patient comfort.