the degree of sensible heat or cold, expressed in terms of a specific scale. See Table of Temperature Equivalents in the Appendices. Body temperature is measured by a clinical thermometer and represents a balance between the heat produced by the body and the heat it loses. Though heat production and heat loss vary with circumstances, the body regulates them, keeping a remarkably constant temperature. An abnormal rise in body temperature is called fever
Normal Body Temperature. Body temperature is usually measured by a thermometer placed in the mouth, the rectum, or the auditory canal (for tympanic membrane temperature). The normal oral temperature is 37° Celsius (98.6° Fahrenheit); rectally, it is 37.3° Celsius (99.2° Fahrenheit). The tympanic membrane temperature is a direct reflection of the body's core temperature. These values are based on a statistical average. Normal temperature varies somewhat from person to person and at different times in each person. It is usually slightly higher in the evening than in the morning and is also somewhat higher during and immediately after eating, exercise, or emotional excitement. Temperature in infants and young children tends to vary somewhat more than in adults.
Temperature Regulation. To maintain a constant temperature, the body must be able to respond to changes in the temperature of its surroundings. When the outside temperature drops, nerve endings near the skin surface sense the change and communicate it to the hypothalamus. Certain cells of the hypothalamus then signal for an increase in the body's heat production. This heat is conducted to the blood and distributed throughout the body. At the same time, the body acts to conserve its heat. The arterioles constrict so that less blood will flow near the body's surface. The skin becomes pale and cold. Sometimes it takes on a bluish color, the result of a color change in the blood, which occurs when the blood, flowing slowly, gives off more of its oxygen than usual. Another signal from the brain stimulates muscular activity, which releases heat. Shivering is a form of this activity—a muscular reflex that produces heat.
When the outside temperature goes up, the body's cooling system is ordered into action. Sweat is released from sweat glands beneath the skin, and as it evaporates, the skin is cooled. Heat is also eliminated by the evaporation of moisture in the lungs. This process is accelerated by panting.
An important regulator of body heat is the peripheral capillary system. The vessels of this system form a network just under the skin. When these vessels dilate, they allow more warm blood from the interior of the body to flow through them, where it is cooled by the surrounding air.
Abnormal Body Temperature
. Abnormal temperatures occur when the body's temperature-regulating system is upset by disease or other physical disturbances. fever
usually accompanies infection and other disease processes. In most cases when the oral temperature is 37.8°C (100°F) or over, fever is present. Temperatures of 40°C (104°F) or over are common in serious illnesses, although occasionally very high fever accompanies an illness that causes little concern. Temperatures as high as 41.7°C (107°F) or higher sometimes accompany diseases in critical stages. Subnormal temperatures, below 35.6°C (96°F) occur in cases of collapse; see also symptomatic hypothermia
) that reckoned from absolute zero (−273.15°C), expressed on an absolute scale
basal body temperature
(BBT) the temperature of the body under conditions of absolute rest; it has a slight sustained rise during the luteal phase of the menstrual cycle
and can be used as an indirect indicator of when ovulation
the temperature of the body of a human or animal; see temperature
core temperature the temperature of structures deep within the body, as opposed to peripheral temperature such as that of the skin.
critical temperature that below which a gas may be converted to a liquid by increased pressure.
normal temperature the body temperature usually registered by a healthy person, averaging 37°C (98.6°F).
risk for imbalanced body temperature a nursing diagnosis accepted by the North American Nursing Diagnosis Association, defined as a state in which an individual is at risk of failure to maintain body temperature within the normal range.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.
systemic inflammatory response syndrome A term that 'was developed to imply a clinical response arising from a nonspecific insult and includes two or more of the following. See Sepsis, Septic shock, Severe sepsis.
Systemic inflammatory responses
Temperature < 36ºC or > 38ºC
Heart rate > 90 beats/min
Respiratory rate pCO2 < 32 mm Hg or > 20 breaths/min
WBC count < 4 x 109 or > 12 x 109 or , or the presence of > 0.10 immature neutrophils
sepsis syndrome A constellation of signs, Sx, and systemic responses caused by a wide range of microorganisms that may eventuate into septic shock; SS is a systemic response to infection
Sepsis syndrome, defining parameters
• Temperature Hypothermia < 35ºC–96ºF or hyperthermia > 39ºC–101ºF
• Tachycardia > 90 beats/minute
• Tachypnea > 20 breaths/minute
• Site of infection Clinically evident focus of infection or positive blood cultures
• Organ dysfunction 1+ end organs with either dysfunction or inadequate perfusion or cerebral dysfunction
• Metabolic derangement Hypoxia–PaO2 < 75 mm Hg, ↑ plasma lactate/unexplained metabolic acidosis
• Fluid imbalance Oliguria–< 30 mL/hr
• WBC counts < 2.0 x 109/L; > 12.0 x 109/L–US: < 2000/mm3; > 12 000/mm3
Note: The confusing semantics of the terms sepsis, sepsis/septic syndrome, and septic shock are unlikely to be resolved in the forseeable future; the terms sepsis and septic syndrome are essentially interchangeable and would in part overlap with septicemia–the early components of a pernicious infectious cascade that has spilled into the circulation; the term septic shock is used when the process becomes virtually irreversible.
McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.
temperature (tem'pe(r)-choor?) [L. temperatura, proportion]
TEMPERATURE REGULATION: Effects of changes in body temperature
The degree of hotness or coldness of a substance. See: illustration
The temperature measured from absolute zero, which is -273.15°C.
The surrounding temperature or that present in the place, site, or location indicated.
The temperature obtained by placing a thermometer in the apex of the axilla with the arm pressed closely to the side of the body for the time recommended by the manufacturer of the thermometer. The temperature obtained by this method is usually 0.5° to 1.0°F (0.28° to 0.56°C) lower than oral. See: Temperature: Axillary
A marker of endocrine, metabolic, or muscle activity; the response of the body to heat or cold in the environment; or the presence of infection, inflammation, among other illnesses; it is one of the vital signs. Body temperature varies with the time of day and the site of measurement. Oral temperature is usually 97.5° to 99.5°F (36° to 38°C). Daily fluctuations in an individual may be 1° or 2°F. Body temperature may be measured by a placing a thermometer in the mouth, the rectum, under the arm, in the bladder, within the chambers of the heart, or in the external auditory canal of the ear. Rectal temperature is usually from 0.5° to 1.0°F (0.28° to 0.56°C) higher than by mouth; axillary temperature is about 0.5°F (0.28°C) lower than by mouth. Oral temperature measurement may be inaccurate if performed just after the patient has ingested cold or hot substances or has been breathing with an open mouth.
Body temperature is regulated by thermoregulatory centers in the hypothalamus that balance heat production and heat loss. Eighty-five percent of body heat is lost through the skin (radiation, conduction, sweating) and the remainder through the lungs and fecal and urinary excretions. Muscular work (including shivering) is a mechanism for raising body temperature. Elevation of temperature above normal is called fever (pyrexia), and subnormal temperature is hypothermia. Other factors that can influence body temperature are age (infants and children have a wider range of body temperature than adults, and elderly have lower body temperatures than others); menstruation cycle in women (the temperature rises in the ovulatory midcycle and remains high until menses); and exercise (temperature rises with moderate to vigorous muscular activity).
The body's temperature in deep internal structures, such as the heart or bladder, as opposed to peripheral parts such as the mouth or axilla. In critical care it is often measured with a thermometer linked to a central venous catheter or pulmonary artery catheter.
The temperature above which distinct liquid and gas phases do not exist.
A condition in which the body temperature is higher in the morning than in the evening.
The temperature above which bacterial growth will not take place.
The average temperature for a stated period in a given locality.
In bacteriology, the temperature below which bacterial growth will not take place.
The temperature of the body, taken orally, in a healthy individual: normally 97.5° to 99.5°F (36° to 38°C).
The temperature at which a procedure is best carried out, such as the culture of a given organism or the action of an enzyme.
See: Temperature: Oral
The temperature obtained by placing a thermometer under the patient's tongue with lips closed for 3 min or by electronic thermometer for the length of time noted on the readout or the manufacturer's direction.
It should not be taken for at least 20 min after ingestion of hot or cold liquids. It is not advisable for infants, those who breathe through the mouth, the comatose or obtunded patients, or the critically ill.
The temperature obtained by inserting a thermometer into the anal canal to a depth of at least 112 in (3.8 cm) and holding it in place for 3 to 5 min or, for electronic thermometers, according to the manufacturer's directions. This method should not be used following a rectal operation or if the rectum is diseased. A rectal temperature is more accurate than either oral or axillary temperatures. It averages about 1°F (0.56°C) higher than the oral temperature and approx. 1.5°F (0.84°C) higher than the axillary temperature. See: Temperature :Rectal
The temperature between 65° and 80°F (18.3° and 26.7°C).
A body temperature below the normal range of 97.5° to 99.5°F (36° to 38°C).
The temperature obtained by placing an electronic probe in the ear canal. Such a reading measures the temperature in the capillary bed of the tympanic membrane and is generally reflective of the core temperature. See: ear thermometry; thermometer, tympanic
Medical Dictionary, © 2009 Farlex and Partners
Patient discussion about temperature
Q. what is the red line when your body temperature drops before you are getting hypothermia?
A. Hypothermia is a condition in which an organism's temperature drops below that required for normal metabolism and function. For people in stage 1 hypethermia, body temperature drops by 1-2°C below normal temperature (35-36°C). Mild to strong shivering occurs. In stage 2, body temperature drops by 2-4°C (35-33 degrees). Shivering becomes more violent. Muscle mis-coordination becomes apparent and movements are slow and labored and there is mild confusuin. In stage 3, body temperature drops below approximately 32 °C (89.6 °F). Shivering usually stops and there's difficulty speaking, sluggish thinking, and amnesia start to appear. Cellular metabolic processes shut down. This is life threatening.
Q. I feel that my temperature is rising, I am worried as it was told to me to not take on any medicine? I am currently in my 1st trimesters and last week I had fever over 100. I took paracetamol and I got well. Again today I feel that my temperature is rising and it has gone pretty high. My body is on high pain l and I think I must meet a doctor this time. What you guys have to say……I am worried as it was told to me to not take on any medicine but I had taken one ………what can happen?
A. First, congratulations for the pregnancy. I agree with falseact, you should see your OB-GYN doctor for a consult. But here I paste a data that might be useful to calm your worry..More discussions about temperature
Acetaminophen or paracetamol labeling, like all OTC medications, instructs consumers who are pregnant or nursing a baby to contact their doctor before use. Acetaminophen or paracetamol has been used for over 40 years and available data indicate that acetaminophen in therapeutic doses does not adversely affect the pregnant mother or the fetus.
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