What is core body temperature?

From the Guidelines

Core body temperature is typically around 37°C, and it is critical to maintain this temperature for optimal enzyme function and cellular processes. The core body temperature represents the temperature of the deep tissues and organs in the body's core, including the heart, liver, and brain, rather than the temperature at the body's surface 1. This temperature is regulated by the hypothalamus in the brain, which acts like a thermostat to maintain homeostasis. The body uses various mechanisms to maintain this temperature, including sweating to cool down when too hot and shivering to generate heat when too cold. Significant deviations from normal core temperature can be dangerous—hypothermia occurs when temperature drops below 35°C, while hyperthermia or fever occurs when it rises above 38°C 1. Core temperature can be measured most accurately using rectal, esophageal, or bladder thermometers, though oral and tympanic (ear) measurements are more commonly used in everyday settings. Some key points to consider about core body temperature include:

• Hypothermia is associated with acidosis, hypotension, and coagulopathy in severely injured patients 1
• Hypothermia in trauma patients increases mortality and blood product transfusions 1
• Maintaining normothermia with core temperatures between 36 and 37 °C is crucial to create optimal pre-conditions for coagulation 1
• Measures to prevent hypothermia include removing wet clothing, avoiding additional heat loss, and increasing the ambient temperature, as well as using forced air warming, warm fluid therapy, and extracorporeal re-warming devices 1.

From the Research

Definition of Core Body Temperature

• Core body temperature refers to the temperature of the internal organs, which is essential for diagnosing and treating temperature-related impairments in patients 2.
• It is the mass-weighted average temperature of body tissues, and its measurement is crucial in various medical and sports settings 3, 4.

Measurement of Core Body Temperature

• The measurement of core body temperature can be done using invasive methods, such as pulmonary artery catheters, esophageal temperature measurement, and rectal temperature measurement 2, 4, 5.
• Non-invasive methods, such as tympanic membrane infrared probes, are also available but may not provide accurate readings 5.
• The choice of measurement method depends on the specific application, such as in intensive care units or sports medicine 4, 5.

Importance of Core Body Temperature

• Core body temperature plays a critical role in maintaining homeostasis and regulating various bodily functions 3.
• Abnormal core body temperatures, such as hypothermia or hyperthermia, can have severe consequences and even be life-threatening 4.
• Accurate measurement of core body temperature is essential for preventing and treating temperature-related illnesses and injuries 2, 4, 5.

Applications of Core Body Temperature Measurement

• Core body temperature measurement is used in various medical settings, including intensive care units, operating rooms, and emergency departments 2, 5.
• It is also used in sports medicine to monitor athletes' body temperatures and prevent heat-related illnesses 4.
• In forensic science, core body temperature measurement can be used to estimate the post-mortem interval and investigate ballistics cases 6.