Skin and Temperature Control Flashcards
What factor cause core body temperature to vary?
External temperature
Activity
Circadian rhythm
Menstrual cycle
What detects body temperature?
Peripheral thermoreceptors
Central thermoreceptors
Where are peripheral thermoreceptors found in the body?
Skin, especially in face, scrotum
Where are central thermoreceptors found in the body?
Spinal cord
Abdominal organs
Hypothalamus
How is heat generated in the body in response to cold stress?
General metabolism
Voluntary muscular activity
Shivering thermogenesis
Nonshivering thermogenesis
How is heat loss from the body reduced in response to cold stress?
Vasomotor control
Behavioural responses
What is hypothermia?
A fall in deep body temperature to below 35C
Who is at risk of cold stress?
Neonates Elderly Vagrants Cold store workers Outdoor pursuits Offshore workers
What is the treatment for cold stress?
Dry/insulate to prevent further heat loss
Slow re-warming (bags, blankets, hot drinks, warm air)
Fast re-warming (immersion in water, extracorporeal circulation)
What vascular effects occur due to cold stress?
Vasoconstriction
Increase in viscosity
Promotes thrombosis
Causes anoxia
How is heat production minimised in response to heat stress?
Decreased physical activity
Decreased food intake
How is heat loss from the body increased in response to heat stress?
Vasomotor control
Sweating
Behavioural responses
What is heat exhaustion?
Body temperature raised in range 37.5-40C
What are the symptoms of heat exhaustion?
Headache Clammy skin Confusion Nausea Profuse sweating Tachycardia Hypotension Weak pulse Fainting and collapse
How is heat exhaustion caused?
Disturbance of the body’s fluid/salt balance due to excessive sweating
What is heat stroke?
Body temperature raised above 40C
What are the symptoms of heat stroke?
Hot dry skin
Circulatory collapse
Who is at risk of heat stress?
Neonates
Elderly
Physical work in hot humid environments
Workers wearing non breathable protective clothing
What is the treatment for heat stress?
Move to cooler environment Remove clothing Fan Sponge with tepid water Give fluids (oral, IV)
What causes fever
Endogenous pyrogens (interleukins 1 and 6)
