Factors affecting body temperature
Many factors affect body temperature. The nurse must be aware of these factors when assessing temperature variables and evaluating deviation from normal.
Age : For new born, the temperature - control mechanisms are immature. An infant' s temperature may respond drastically to changes in the environment.
Temperature regulation is unstable until children reach puberty. Older adults are sensitive to temperature extremes because of deterioration in control mechanisms, reduced sweat gland activity, reduced amounts of subcutaneous fat and reduced metabolism.
Exercise: Muscle activity causes increased metabolism by increasing carbohydrate and fat breakdown. Any form of exercise can increase heat production and thus body temperature.
Hormone level: Women generally experience greater fluctuations in body temperature than men. Hormonal variations during menstrual cycle cause body temperature fluctuation.
Temperature changes occur in women during menopause. (cessation of menstruation)
Circadian rhythm: Body temperature normally changes 0.5º to 1º C during 24 hour period. The temperature is usually lowest between 1.00 AM and 4.00 AM.
Stress : Physical and emotional stress increases body temperature through hormonal and neural stimulation. These physiological changes increase metabolism, which increases heat production.
Environment Environment influences body temperature. In a very warm room, the body temperature will be elevated. In a cold weather , the body temperature may be low because of extensive radiant and conductive heat loss.
Temperature alterations : Changes in body temperature can be related to excess heat production, excessive heat loss, minimal heat production, minimal heat loss or any combination of these.
Fever : Hyperpyrexia or fever occurs because heat loss mechanisms are unable to keep pace with excess heat production, resulting in an abnormal rise in body temperature.
Hyperpyrexia: An elevated body temperature related to the body' s inability to promote heat loss or reduce heat production is hyperthermia. Any disease or trauma to the hypothalamus can impair heat loss mechanisms.
Heat stroke: Prolonged exposure to the sun or high environmental temperature can overwhelm the body' s heat loss mechanisms.
Heat also depresses hypothalamic function. These conditions cause heat stroke, a dangerous emergency condition with a high mortality rate.
Patients at risk for heat stroke are the very young, very old, cardio vascular condition, diabetes and alcoholics.
Heat loss during prolonged exposure to cold overwhelms the body ability to
produce heat causing hypothermia.