Do Standard Monitoring Sites Reflect True Brain Temperature When Profound Hypothermia Is Rapidly Induced and Reversed? 

Abstract

When profound hypothermia is rapidly induced and reversed, temperature measurements made at standard monitoring sites may not reflect cerebral temperature. Measurements from the nasopharynx, esophagus, and pulmonary artery tend to match brain temperature best but only with an array of data can one feel comfortable disregarding discordant readings.

Perioperative temperature measurement and management: moving beyond the Surgical Care Improvement Project

“…Usually, commonly-used monitoring sites such as tympanic, bladder, esophageal, nasopharyngeal, and pulmonary artery are similar to brain temperature [16]. However, all [16].…”

“…However, all [16]. A solution to monitoring core temperature sites in lieu of cerebral temperature for non-severely brain injured patients, for whom large rapid changes in temperature during surgery are anticipated, is to monitor multiple sites to help identify outliers [16].…”

“…A solution to monitoring core temperature sites in lieu of cerebral temperature for non-severely brain injured patients, for whom large rapid changes in temperature during surgery are anticipated, is to monitor multiple sites to help identify outliers [16]. Since core body temperature provides a fair approximation of brain temperature [16], except in cases of severe brain injury [25][26][27], and rapid changes in body temperature [16], it may partially explain why hypothermia based on core temperature measurements provides neuroprotection.…”

“…Rectal temperature has been shown to adjust more slowly than other sites for measuring core temperature contributing to its lower accuracy [15,17]. The least accurate location to measure temperature is the skin as it is subject to peripheral vasoconstriction induced by thermoregulatory mechanisms in the presence of hypothermia [16]. Skin temperatures are frequently monitored because they are easily accessible.…”

Significance of Differences Between Brain Temperature and Core Temperature (Delta T) During Mild Hypothermia in Patients With Diffuse Axonal Injury

“…However, the various sites commonly used for temperature monitoring, such as the bladder, tympanic membrane, esophagus, pulmonary artery blood, and jugular bulb, may show discrepancies. 7,18) Recently, the significance of differences between brain temperature and core temperature (delta T) has attracted attention. The brain temperature of patients with TBI can differ significantly from body temperature, 20) suggesting that this temperature difference might provide useful prognostic information.…”