Temperature control and vital signs Flashcards
What is the average resting pulse range?
60-100 bpm
What is the average blood pressure range?
90/60 - 120/80
What is the average resting respiratory rate?
12-20 breaths per minute
What is the normal oxygen saturation level?
≥96%
What is the average core body temperature?
37.8°C
What is the name given to the optimum temperature for cellular function and metabolism?
Normothermia
What are the risks of increased body temperature?
Protein denaturation, nerve malfunction, convulsions and death
What are the risks of decreased body temperature?
Decreased cellular metabolism and function, which can be fatal
What is the normal tympanic temperature range?
36-37.5°C
What core body temperature range is considered to be a fever?
38-40°C
What core body temperature is considered as hyperthermia?
> 40°C
What core body temperature is considered as hypothermia?
<35°C
What is the diurnal temperature range?
The change in temperature over the course of 1 day. Temperature is lower in the morning than at night
When during the menstrual cycle is core temperature higher?
2nd half of the cycle from ovulation
What are the 4 methods of heat gain?
Metabolic heat gain
Radiation
Convection
Conduction
What are the 4 methods of heat loss?
Radiation
Conduction
Convection
Evaporation
What is meant by the Basal Metabolic Rate?
The minimum amount of energy required to sustain vital body functions
How does shivering increase heat production?
Through muscle activity, due to the increase in metabolic rate
Name 3 hormones that can increase BMR.
Adrenaline, noradrenaline and thyroxine
How does sweating increase heat loss?
Energy is drawn from the skin surface to convert water from a liquid to a gas
Which division of the autonomic nervous system controls sweating?
Sympathetic nervous system
Where are the central thermoreceptors found in the body?
In the hypothalamus, spinal chord and abdominal organs
Where are the peripheral thermoreceptors found in the body?
In the skin
What are the 3 main effectors of temperature control?
Skeletal muscle
Skin arterioles
Sweat glands
Which region of the hypothalamus is activated by cold?
Posterior hypothalamic centre
Which region of the hypothalamus is activated by warmth?
Anterior hypothalamic centre
How do the skin arterioles decrease heat loss?
They undergo vasoconstriction, so blood flow to the skin surface is reduced to decrease radiation
How do skeletal muscles increase heat production?
Increased muscle tone and shivering increases metabolic rate
How do the skin arterioles increase heat loss?
They undergo vasodilation, so blood flow to the skin surface is increased to increase radiation
How do skeletal muscles decrease heat production?
Decreased muscle tone, so decreased metabolic rate
What chemicals are released from macrophages to trigger fever?
Endogenous pyrogens (e.g. interleukins)
What do endogenous pyrogens stimulate the release of during the trigger fever?
Prostaglandins in the hypothalamus
What effect do prostaglandins have on the hypothalamus?
They act on the hypothalamic thermo-regulatory centre to reset the set point at a higher temperature, initiating the mechanisms to heat the body
What can trigger the end of a fever?
Treatment of the original cause or antipyretics
What happens at the end of a fever?
The endogenous pyrogen release is ceased, so prostaglandin production is ceased, meaning the hypothalamus can reduce the body temperature to the normal set point
