The difference between a positive patient outcome and a complicated recovery can be a matter of degrees. The potentially adverse effects of even mild perioperative hypothermia, defined as a core body temperature of less than 36.0°C (96.8°F)¹, are numerous and well-documented.
The major cause of intraoperative hypothermia is the redistribution of heat from the core to periphery due to anesthetic-induced vasodilation.¹,² Known as redistribution temperature drop, this physiological reaction can cause unwarmed surgical patients to experience a core temperature drop of up to 1.6°C during the first hour of surgery.²
Hypothermia caused by redistribution is almost impossible to reverse quickly.³ Proactively monitoring and managing core body temperature can help you own the normothermic temperature zone (36.0°C - 37.5°C)⁴,⁵and protect patients from unintended perioperative hypothermia.
The maintenance of a normal core body temperature, normothermia, is a crucial component of patient safety. Core temperatures outside the normal range pose a risk in all patients undergoing surgery and have been associated with an increased risk of surgical complications, including:
Redistribution is a major cause of unintended hypothermia. Prewarming—actively warming surgical patients before the induction of anesthesia—is an effective way to help prevent it. Prewarming combined with intraoperative warming using forced-air warming blankets or gowns can reduce the temperature drop associated with redistribution and help maintain normothermia, which has been shown to reduce the rate of hypothermia-associated complications.15-16 The practice of prewarming is being recommended in clinical practice guidelines and quality improvement initiatives across the globe.17⁻21
One challenge in the management of patient temperature lies in effective temperature measurement and monitoring. Although core temperature is a vital sign, it is frequently thought of as being less important than other vitals monitored during anesthesia. Core temperature should be continuously monitored so that it can be effectively managed, ensuring patients stay within the normothermic temperature zone.
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