Environmental Emergecies Flashcards
Convection
Loss of body heat to the atmosphere when air passes over the body
Conduction
Transfer of heat through direct physical touch with nearby objects
Respiration
Heat is lost through exhalation of warm air and inhalation of cold air
Evaporation
Conversion of a liquid or solid into a gas; evaporation of sweat is a means by which the body is cooled
Radiation
Transfer of heat from the surface of one object to the surface of another without physical contact between the objects
Stages of hypothermia
- Shivering, does NOT occur when body temp is below 90 F
- Apathy and depressed motor function
- Decreased level of consciousness
- Decreased vital signs
- Death :(
Mydexerma coma
Life-threatening late complication of hypothyroidism that may be precipitated by exposure to cold temperatures as well as to illness, infection, trauma, or certain drugs.
S&S of hypothermia
- Decreasing mental status:
- Amnesia, memory lapses, and incoherence
- Mood changes
- Impaired judgement
- Reduced ability to communicating
- Dizziness
- Vague, slow, slurred, thick speech
- Drowsiness progressing to unresponsiveness - Decreasing motor and sensory function
- Changing vital signs (start of high HR, drops to low HR)
Active rewarming
Technique of aggressively applying external sources of heat to
patients to re-warm their body.
Hypothermia
An overall reduction in body temperature that affects the entire
body; also called hypothermia or generalized cold emergency.
Hyperthermia
Abnormally high core body temperature resulting from failed
thermoregulation; core body temperature above the normal
37 °C (98.6 °F).
Local cold injury
Damage to body tissues in a specific part of the body resulting
from exposure to cold; frostbite
Passive rewarming
The use of patients’ own heat production and conservation
mechanisms to rewarm them (for example, placing patients in
a warm environment and covering them with blankets).
Thermoreceptor
A sensory receptor that is stimulated by temperature.
Urban hypothermia
Hypothermia precipitated by cold environments; affects people
who live on the streets in cold weather or whose indoor
environment is too cold.
Water chill
The increase in rate of cooling in the presence of water or wet
clothing.
Wind chill
The combined cooling effect of wind speed and environmental
temperature.
“Thermostat of the body”; part of brain that controls body temp
Hypothalamus
How body warms & cools itself
Warming body:
- chemical reactions (metabolism), which results, for the most part, when the body converts food into energy.
- Hormones released by the adrenal glands will also increase metabolism, producing heat as a by-product.
- shivering (involuntary contractions of the muscles)
- heat is conserved by vasoconstriction of the blood vessels in the extremities and nonessential parts, which shunt blood to the core
- Other methods of conserving heat include moving to a warmer environment, putting on a coat or thicker clothes, folding your arms, and assuming a fetal position.
Cooling body:
- blood vessels in the periphery vasodilate and send the warm blood to the surface of the skin, which helps get rid of heat through radiation and convection. This will only work if the environment is cooler than the skin temperature.
- The cardiovascular system increases cardiac output (tachycardia and contractile force), which increases the amount of blood reaching the skin to be cooled.
- The respiratory system eliminates heat through evaporation during exhalation.
Heat cramps
Painful muscle spasms (cramps) that are usually a result of profuse sweating combined with the loss of electrolytes and water.
- This causes the larger muscles (such as abdominal muscles, gluteus muscles, and hamstrings) to cramp.
- Generally, patients with heat cramps only need to be removed from the hot environment, rest, and slowly replace fluids by drinking water and/or sports drinks.
Heat exhaustion
Occurs when patients overexert themselves in a hot, humid environment, causing profuse sweating and loss of electrolytes, which may cause the body to go into a mild form of shock.
Signs and symptoms:
- headache
- weakness
- dizziness
- tachycardia
- nausea, vomiting
- syncope.
- slightly warm to normal to cool skin (patient is still sweating)
Heat stroke
Body is no longer able to use its normal mechanisms (sweating, vasodilation) to get rid of heat.
- The temperature can become so high that tissue/cells are destroyed
S&S:
- Hot, dry, flushed skin (sweating has ceased or is at a bare minimum),
- Decreased level of consciousness or are unconsciousness
- Signs of profound shock
- Body temperature may increase rapidly to temperatures as high as 106 °F
S&S of pit viper bite (rattlesnakes, copperheads, and water moccasins)
- obvious fang mark
- pain at site bitten
- weakness
- dizziness
- sweating
- chills
- thirst
- nausea and vomiting
- signs of shock
- respiratory distress
- bloody urine
- these bites may affect the body’s ability to clot.