Hypothermia and Cold Water Survival Flashcards
Medical emergency that occurs when the body loses heat faster than it can produce
Hypothermia
Hypothermia is caused by prolonged exposure to water temperatures colder than ___
77°F
Extremities squeeze warm blood to the core to protect vital organs
Peripheral Vasoconstriction
Water will rob the body of heat ___ times faster than air alone
25
Movement ___ heat loss
Increases
In the water, heat loss can be minimized by ___
Protecting head, neck, and thorax. Get as much out of the water as possible. HELP.
HELP
Heat Escape Lessening Position
The majority of the body’s heat loss occurs from the ___
Head, neck, and thorax
Body’s natural tendency when reacting to cold
Hunch shoulders, cross arms in front, and crouch
Vasoconstriction ___ blood pressure
Increases
Vasoconstriction is caused by ___
Contraction of the muscular walls
During vasoconstriction, extremities are ___
Pale and more prone to cold injuries
With normal blood volume, your body can ___
Circulate enough fluids to your muscles and organs to maintain core temperature
Dehydration causes ___
Reduced blood volume, faster heart beat, and increased blood pressure
Factors that accelerate the onset of hypothermia
- Prolonged immersion in water colder than body temperature
- Sea spray
- Air temperature
- Wind chill
- Movement in cold water
- Unprotected major heat loss areas
- Dehydration
- Thin physique
1-10-1 rule
1 minute for controlled breathing
10 minutes of meaningful movement
1 hour of conciousness
Who came up with the 1-10-1 rule? (bonus question)
Dr Gordon Giesbrecht, professor of thermophysiology at the University of Manitoba
Top factors affecting cold water survival time
- Water temperature
- Exposure time
- Protective wear
- General circulatory health
- Age
- Body fat
- Control breathing
- Don’t panic
- Will to live
The perceived decrease in air temperature felt by the body on exposed skin due to the flow of air
Wind chill
Wind chill ___ the risks of adverse effects such as frostbite
Increases
Damage to the skin tissue caused by freezing
Frostbite
Very cold skin and freeze in ___
Minutes or seconds
Frost nip is a ___
Mild form of cold injury
Commonly affected areas for frost bite and nip
Earlobes, cheeks, nose, fingers, and toes
Risk factors for frost bite and nip
Alcohol, smoking, previous cold injuries, fatigue, and diseases (diabetes)
Insufficiently protected and exposed extremities are prone to ___. Water ___ the cooling process.
Cold injuries
Accelerates
Tissue freezing causes ___ formation and other changes that damage and eventually kill ___
Ice crystal formation
Cells
Ice formation causes what effect on cells?
Causes water to flow out of the cells, prevents blood flow oxygenation and natural rewarming process
Symptoms of frostbite
Cold sensation, white/yellow skin, numbness, clumsiness
Extent of permanent injury from frostbite is determined by ___
How long the tissue remains frozen
Many patients experience ___ in the frostbite affected part during rewarming
Severe pain
Frost nip is treated by ___
Rewarming with passive heat source (blowing warm air, placing under armpits, etc)
Frost bite must be ___ treated
Medically
Stages of frost bite injuries are classified as ___ degrees
1st through 4th
___ degree frostbite is a superficial injury
1st through 2nd
___ degree frostbite is a deep tissue injury
3rd through 4th
Ice team precautions
- Vasodilation (keep response vehicle cool)
- Stay hydrated
- Extra head and hand protection
Monitor team for signs of possible cold injury
- Shivering
- Fatigue
- Heat exhaustion
- Sluggishness/slurred speech
4 conditions of hypothermia
Mild
Moderate
Severe
Profound
Mild condition of hypothermia
Core body temperature between 90-95°F
Signs and symptoms of mild hypothermia
- Conscious and alert
- Vigorous shivering
- Pain and numbness
- Some loss of movement (fingers and toes)
Moderate condition of hypothermia
Core body temperature between 82-89°F
Signs and symptoms of moderate hypothermia
- Conscious or semi-conscious
- Drowsy/moderate clouding of mental faculties
- Shivering not present
Severe condition of hypothermia
Core body temperature between 75-81°F
Signs and symptoms of severe hypothermia
- Unconscious
- Weak vital signs
- Muscular rigidity
- Dilated pupils are poorly reactive to light
Profound condition of hypothermia
Core body temperature below 75°F
Signs and symptoms of profound hypothermia
- No vital signs
- Muscular rigidity
- Pupils are fixed and dilated
Circulation of warm fluids inside the chest cavity
Thoracic lavage
