7.3 Flashcards
If body temperature falls significantly below this (35•C) then a person is said to be suffering from
Hypothermia
Normal body temperature =
37•C
Hypothermia is when body temperature falls significantly and the normal heat conservation and heat generation responses of the body are
Unable to bring the body temperature back up
When body falls to 35•C, the normal heat conservation and heat generation responses of the body are unable to Bring the body temperature back up, other words:
Negative mechanism fails
As the body temperature falls, the body’s rate of metabolism slows down. This happens because molecules have
Less kinetic energy, so enzyme-controlled reactions happen more slowly, as a result metabolic reactions involved in respiration slow down (example of positive feedback)
Positive feedback is the process which results in a factor in the body’s interval environment, such as temperature, that departs from its normal level becoming
Further from the norm
Positive feedback is not common. Usually harmful such as temperature falls, continues to fall and enzymes become less active so less heat is
Released and temperature continues to fall
Good form of positive feedback is
Labour
Labour
⬇️
Cervix opens
⬇️
Oxytocin released
⬇️
Oxytocin increases contraction
⬇️
Cervix stretches more
⬇️More oxytocin is released
Positive feedback is a deviation from normal conditions and is amplified leading to a
Further deviation
Hypothermia is a risk for:
Elderly - cost of heating/inactive less heat produced via respiration
Young and fit - exposed to extreme cold; air temperature is very cold; heat is lost from body rapidly
Outdoor activities - climbing/walking; experience difficulties (injury/weather) that keep them exposed to cold weather for longer than they had anticipated
Initial symptoms of hypothermia:
- may not recognise it
- events stop feeling cold
- become relaxed or sleepy
At initial symptoms of hypothermia it is important to give the
Correct first aid treatment at this point
Later symptoms of hypothermia include:
- heart rate slows
- arterioles dilate
- start to feel warm
- may want to remove clothing
After later symptoms they slip into
Unconsciousness
Hyperthermia is a condition in which the body temperature rises above
Normal
Our bodies mainly lose heat by
Sweating
If someone is dehydrated they may not produce enough sweat.
If the air is humid (I.e. Saturated with water vapour) then swear may not
Evaporate quickly enough to bring body temperature down
As body temperature rises above the normal level the person starts to feel ill. If the body temperature rises above 41•C the hypothalamus is no longer able to
Regulate body temperature and it continues to rise
Heat stroke occurs when body temp rises above 41•C. The inability to regulate body temperature and its continued rise will make the person start to feel
Light headed and sick
First aid treatment for hyperthermia is to bring the
Body temperature down as soon as possible
(Hyperthermia) body temperature is brought down by:
- Applying cold water to the body
- Exposing the skin so that the water can evaporate easily
(Hyperthermia) the person should be given cold drinks if they are able to
Swallow
Fever is a medical sign that body temperature has
Risen above its normal level
Fever is a symptom of
Disease in which body temperature is raised 1-2•C above normal
Fever is different from hyperthermia because the body releases substances called
Pyrogens
(Fever) pyrogens change the body’s set point, so that the person feels cold, has an increased heart rate and shivers even though their body temperature is
Normal
First aid treatment for hypothermia:
-send for medical help
-prevent further body heat loss and warm the casualty gradually (wrapping them in layers in a warm room)
-put casualty to bed and keep them
Well covered
-do not try to put causally in bath
-offer the casualty warm drinks
