Body temperature
Last reviewed: 23.04.2024
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Usually body temperature is measured in the armpit, but its measurement in the rectum sometimes has an independent value, for example, with general cooling of the body, damage to the tissues of the armpit, and in gynecology to measure basal body temperature (to determine the date of ovulation).
The temperature of the body in the armpit is considered normal if it is located between 36 and 37 ° C and varies within a day from a few tenths to 1 ° C. A noticeable decrease in it is observed rarely (general exhaustion of the body, heart failure, intoxication by some toxic substances, endocrine disorders).
Fever is a protective-adaptive reaction of the body that arises in response to the action of various stimuli and is expressed in the restructuring of thermoregulation to maintain a higher than normal body temperature. Body temperature within 37-38 ° C is called subfebrile fever. 38-39 ° С - moderate fever, 39-41 ° С - high fever, over 41 ° С - hyperpyretic fever.
The temperature measured in the armpit is considered normal if it is fixed in the range from 36 to 37 ° C and varies within a day from a few tenths to 1 ° C. Lowering of temperature is rare when it is exhausted, heart failure, some intoxication.
Body temperature in the range 37-38 ° C is considered subfebrile, 38-39 ° C - moderate fever, 39-41 ° C - high fever, above 41 ° C - hyperpyretic.
[Causes of fever
The causes of fever are varied. Among them, the main is an infectious process of various origins. However, a non-infectious inflammatory process is possible (for example, with myocardial infarction or with a so-called autoimmune inflammation), sometimes the cause of fever may remain unclear for a long time. At present, even the syndrome of "fever of unknown origin" is isolated with an increase in body temperature above 38 ° C for at least 3 weeks.
Influence on heat production with an increase in body temperature is exerted by the endocrine system: for example, when the function of the thyroid gland is increased, subfebrile is often detected.
The temperature rise can be with the defeat of the central nervous system, including purely functional origin - "thermoregulatory neurosis," but the temperature does not practically exceed the subfebrile one.
At present, attention is still paid to the type of temperature curve that is recorded with the daily morning and evening temperature rise.
Types of fever
- constant (febris continua) - temperature fluctuations do not exceed 1 ° C during the day, usually holds within 38-39 ° C;
- Relaxing, or remittent (febris remiftens), - daily fluctuations 1-2 ° C (for example, in purulent processes);
- alternating (febris intermittens), - temperature rises to 39-40 ° C for a short time (hours) alternate with a decrease to normal and with a new increase in 2-3 days (as in malaria);
- recurrent febrile (febris recurrens) - unlike intermittent fever, the fever lasts for several days, it changes temporarily normal with a subsequent new period of increase;
- hectic (exhausting) fever (febris hectrica) with swings of temperature during the day 3-5 ° C (for example, with sepsis);
- wavy (febris undulans) with a gradual increase and decrease in the maximum diurnal temperature rises;
- an irregular febrile (febris irregularis) with irregular increases in temperature to different numbers occurs most often.
The measurement of temperature in the rectum is of independent importance. It is sometimes carried out by gynecologists, who ascertain the temperature rise in women to subfebrile figures in the second half of the menstrual cycle (after ovulation).