Environmental Illnesses Flashcards
regulating body temperature
normal is 37C or 98.6F
- a few degree change is significant
role of the hypothalamus
part of the brain that controls thermoregulation
- receive signals from skin and central receptors if the body is too hot or too cold and reacts accordingly
human thermoregulation responses
warm/hot: heat loss (vasodilation or sweating)
cold/cool: heat conserving (vasoconstriction or shivering)
mechanisms of heat loss
radiation (air)
conduction (solid ground/liquid)
convection (flowing air/water removes heat)
evaporation (liquid to gas uses energy)
- heat moves from area of hot to cold
Sweating in different enviroments
Occurs when the temperature of either the skin OR the body’s core increases
cold = sweating should be minimized (remove layers prior to hard work)
Warm = evaporative heat loss, any sweat that does not evaporate will not cause cooling
Regulation in Cold Environment
Vasoconstriction: at the skin to keep core warm
Shivering when vasoconstriction does not work
General factors affecting regulation of body temperature
- temp of surrounding air and water
- air humidity
- wind speed
- clothing properties
- total insulation (clothing)
- skin moisture
- physiological factors (heat production)
Wind Chill
in a cold environment low ambient temperature and wind combine to increase heat loss through convection
Heat and Humidity
in a hot environment heat and humidity combine to increase heat stress
Causes of Heat/Cold related illnesses
- strenuous work/exercise in extreme temperatures
- work/exercise in clothing inhibiting heat exchange
- working inside, hot, humid, poorly vented areas
- exposure to cold temps (wet, wind)
- tight footwear
- recreation in cold, wet, windy condt.
Casualty Risk Factors
-Age (elder - young)
-Prior history of heat/cold illness
-Respiratory /cardiovascular disease
-Diabetes/ other poor circulatory conditions
-medications that eliminate water from the body
Heat related illnesses
-can affect anyone
-in athletes, leading cause of death = heat stroke
- most sports have rules around temp/humidity
3 categories heat related illnesses
- heat cramps
- heat exhaustion
- heat stroke
Heat cramps
painful spasms of skeletal muscles that develop rapidly and after periods of physical exertion in warm or moderate temperatures
- profuse sweating
- lack of hydration
Heat exhaustion
body’s temp rises and thermoregulatory responses are activated to compensate
- early sign thermoreg. being overwhelmed
- not always response to heat cramp
- body temp might be slightly elevated/normal
- loss fluid (sweating) = decrease blood volume
- BF to skin incr. to incr. heat loss but reducing BF to vital organs
Heat stroke
body’s thermoreg. mechanisms are overwhelmed by heat stress and begin to stop functioning
- least common (most severe)
- S/S of heat exhaustion are ignored
- sweating stops (body’s fluid levels are too low)
- body temp rises usually above 40
- brain and vital organs fail at temp and if the body is not cooled, leads to seizures coma and death
Care for heat-related illnesses
-water on torso (if layer of clothing there)
- electrolyte replacements
- heat cramps = return when cramps stop
- heat exhaustion/stroke do not return to play on the same day
treatment for heat cramps
- water/electrolytes
- loosen tight clothing, remove padding from torso
- gentle stretching
treatment for heat exhaustion
- water/electrolytes
- loosen tight clothing, remove padding from torso
- DO NOT dry skin
- active cooling
- water on torso
- fan skin
treatment for heat stroke
- water/electrolytes (if alert)
- loosen tight clothing, remove padding from torso
- DO NOT dry skin
- aggressive cooling
- immerse in cool water
- water on torso
- fan skin
Cold related injuries
- frostnip
- frostbite
- hypothermia
Frostnip
minor form of frostbite
S/S: skin appear pale
pain/stinging in the area
frostbite
- water inside/ between cells freeze and swell
- ice crystals damage /destroy the body’s cells, blood vessels, and nerves
S/S: skin white/waxy
cold and hard to touch
lack of feeling in the area
after thaw = experience buring, redness, pain, tenderness, and blisters
types of frostbite
superficial:
- blisters after thaw
- result in small amount of tissue lost or none at all
Deep:
- dark, hemorrhagic blisters after thaw
- likely to result in tissue lost
treatment for frostbite
- gently handle
- do not rub or apply snow/ice
- thaw if only you are sure it will NOT freeze again
- submerge in warm water (NOT HOT)
- gauze between fingers and toes and seek medical attention
Hypothermia
-b temp decrease 37-35
- LF especially when temp drops below 28C
- four distinct phase
1. cold stress - non hypothermic
2. mild hypothermia
3. moderate hypothermia
4. severe hypothermia
Cold stress
normal or near normal functions
S/S: shivering
normal mental status
normal/ near normal motor functions
Mild hypothermia
near normal functions including heart rate and resp. rate
S/S: vigorous shivering, complains of cold
- decreased motor and sensory function
- difficulty taking care of self
Moderate hypothermia
slow/ weakened resp and heart rate
S/S: weak and intermittent shivering/ stops later
- c/o cold
- lack speech
- impaired judgement
- decrease LOR
- eventually unresponsive
Severe Hypothermia
shallow/absent respiration
weak/absent pulse
S/S: no shivering
- unresponsive
- stiffening body tissue
check pulse and respiration for 60 sec
- CPR if neither detected
Assisting Responsive Drowning Patient
rescue only done by trained professionals (Do not put yourself in danger)
- rescue from land
1. talk (them through it)
2. throw (rope)
3. reach (rigid object)
Cold water Immersion and Drowning
faster than hyperthermia caused by cold air exposure
4 phases:
1. Cold shock response (1-2 mins, rapid cooling of skin causing gasp -> hyperventilation)
2. cold incapacitation (15 mins, loss of coordination and weakness)
3. hypothermia (30 mins 30 mins)
4. Circum-rescue collapse (prior, during, or after a rescue S/S = syncope -> cardia arrest)
