Short interruptions between pre‐warming and intraoperative warming are associated with low intraoperative hypothermia rates

Abstract

Inadvertent perioperative hypothermia, defined as a core body temperature less than 36.0°C, increases the risk of myocardial ischemia, arrhythmia, intraoperative blood loss, transfusion and wound complications in surgical patients. 1-3 The scientific evidence of measures to prevent inadvertent intraoperative hypothermia has been summarized in the NICE and the German and Austrian guidelines. 2,3 Active pre-warming with forced-air combined with intraoperative forced-air warming was recommended with the highest level of evidence. 3

Perioperative Prewarming: Heat Transfer and Physiology

“…During periods involving discontinuation of active warming, such as when transporting the patient from the preoperative area to the OR, the peripheral thermal compartment can lose a substantial amount of stored heat. Even with adequate prewarming intensity and duration, an uninsulated patient can lose a substantial amount of heat from the time that prewarming ends to when anesthesia induction begins 43 . Because skin temperature is much higher than air temperature and the mean radiant temperature of the OR, uninsulated prewarmed patients lose heat faster than nonprewarmed patients; 41 therefore, it is critical to insulate patients, especially their hands and feet, when it is not feasible to perform active warming.…”

Perioperative Hypothermia in Children

“…It has been shown in adults that pausing forced-air warming during washing draping can increase the risk of intraoperative hypothermia in a time-dependent ma [84]. This effect can be expected to be even more important in paediatric pati Therefore, paediatric patients should be continuously warmed, if possible.…”

Perioperative Hypothermia—A Narrative Review

“…In general, the recommendations are to measure core temperature, to prewarm the patients actively before induction of anaesthesia, to warm the patients during anaesthesia, and to use fluid warming when larger amounts of fluids are used. Using this approach, postoperative hypothermia rates of less than 15% are possible [89,90]. However, it seems reasonable to pay detailed attention in order to prevent money from being spent on warming equipment without obtaining the desired benefit for the patients.…”

“…There is also no need to stop active warming during washing and draping, as there is no evidence that this might increase the risk of infection [99]. Nevertheless, there is clear evidence that long interruption times in active warming therapy increase the risk for hypothermia [89]. It also makes sense to insulate the parts of the body surface that cannot be actively warmed because insulation can reduce heat loss by 30% [100,101].…”