Core temperature

Core temperature, also called core body temperature, is the operating temperature of an organism, specifically in deep structures of the body such as the liver, in comparison to temperatures of peripheral tissues.

Temperature control (thermoregulation) is part of a homeostatic mechanism designed to keep the organism at optimum operating temperature, as it affects the rate of chemical reactions. In humans this optimum temperature is convert|36.8|C|lk=on (see Normal human body temperature), though it varies regularly as controlled by one's circadian rhythms with the lowest temperature occurring about two hours before one normally wakes up. An organism at optimum temperature is considered "afebrile" or "apyrexic".

Temperature examination in the rectum is the traditional gold standard measurement used to estimate core temperature (oral temperature is affected by hot or cold drinks and mouth-breathing). Rectal temperature is expected to be one Fahrenheit degree higher than an oral temperature taken on the same person at the same time. New ear thermometers measure eardrum temperature using infrared sensors. The blood supply to the tympanic membrane is shared with the brain. However, this method of measuring body temperature is not as accurate as rectal measurement and has a low sensitivity for fevers. [In a systematic review, infrared ear thermometry for fever diagnosis in children finds poor sensitivity. J Clin Epidemiol. 2006 Apr;59(4):354-7. Epub 2006 Feb 20.] One report found this method missed four out of ten fevers in a group of children.Fact|please cite the referenced report.|date=August 2008 Ear temperature measurement may be acceptable for observing trends in body temperature but is less useful in consistently identifying fevers.

External links

* Cite web
last = Wong
first = Lena
title = Temperature of a Healthy Human (Body Temperature)
work = The Physics Factbook
year = 1997
url = http://hypertextbook.com/facts/LenaWong.shtml