2. Cold-Related Emergencies
• When surrounded by air or water cooler
than body temperature, body loses
heat.
• Normal body temperature is 98.6°F.
• If heat escapes faster than the body
produces it, the body temperature falls,
and cold injuries result.
3. How Cold Affects the Body (1 of 2)
• The body has two internal mechanisms to
maintain body temperature.
• Vasoconstriction
• Tightening of blood vessels
• Can cause discomfort, numbness, loss of
dexterity, cold injuries
• Shivering
• Stops when core temperature falls
between 86 and 90°F
4. How Cold Affects the Body (2 of 2)
• Physical activity produces heat.
• Heat loss increases if clothes become wet
with perspiration.
• Susceptibility can be minimized by:
• Proper hydration and nutrition
• Avoiding alcohol, caffeine, and nicotine
• Limiting periods of inactivity
5. Heat Loss from the Body (1 of 2)
• Four mechanisms of heat loss:
• Conduction
• Direct contact with colder object
• Convection
• Loss of heat by air blowing over skin
• Evaporation
• Conversion of liquid on skin to vapor
6. Heat Loss from the Body (2 of 2)
• Four mechanisms of
heat loss (cont’d):
• Radiation
• Heat given off
to cooler air
• Accounts for
the greatest
heat loss
7. Susceptibility to Cold Injury
• Physically unfit
• Dehydration
• Very lean people
• Elderly people
• Alcohol, caffeine
• Nicotine
• Inadequate nutrition, illness, injury
• Experienced a previous cold injury
8. Effects of Altitude
• Air temperature drops 3.6°F
every 1,000 feet.
• Winds are more severe.
• More susceptible to frostbite
above 8,000 feet
9. Effects of Water
• Water can conduct heat away from
the body much faster than air of the
same temperature.
• Wet clothing accelerates heat loss.
10. Effects of Wind
• Wind increases heat loss from skin
exposed to cold air.
• Windchill is the combined effect of
the ambient temperature and wind
speed.
11. Effects of Metal and Liquid
Fuels
• Can conduct heat away from
skin rapidly
• Contact can cause almost
instantaneous freezing
13. Minimizing Effects of Cold on the
Body (2 of 2)
• Middle layer insulates.
• Should be effective when wet.
• Synthetics are better than natural fibers.
• Wool
• Outer layer protects against wind.
• Waterproof
• Wind resistant
• “Breathable”
• Hat
14. Nonfreezing Cold Injuries
• Can occur when conditions
are cold and wet and hands
and feet cannot be kept warm
and dry
18. Trench Foot
• Develops when skin on the feet is exposed to
moisture and cold for 12 hours or longer.
• Caused by:
• Wearing wet boots and shoes
• Prolonged immersion of the feet in cold
water
• Rubberized or tight-fitting boots increase risk.
19. Recognizing Trench Foot and
Immersion Foot
• Itching, numbness, tingling pain
• Swollen feet and pale skin cold to touch
• Red or bluish blotches on the skin
• Sometimes open weeping or bleeding
20. Care for Trench Foot
• Dry the skin.
• Rewarm foot gradually.
• Care for open weeping areas.
• Use mild soap and water.
• Apply a breathable dressing.
21. Freezing Cold Injuries
• Occur when air temperature is below freezing
• Frostnip
• Freezing is limited to skin surface.
• Frostbite
• Freezing extends into the flesh.
24. Care for Frostnip
• Gently warm affected area.
• Do not rub the affected area.
25. Frostbite
• Two ways of
damage:
• Tissue freezing
• Obstruction of blood
supply to the tissue
• Affects feet, hands,
ears, and nose
26. Recognizing Frostbite (1 of 2)
• White, waxy, or grayish yellow skin
• Part feels cold and numb
• Tingling, stinging, aching
• Stiff or crusty skin
• Underlying tissue is soft
27. Recognizing Frostbite (2 of 2)
Indications of deep
frostbite:
•Part feels cold, hard, and
solid and cannot be
depressed.
• Blisters
• Pale, waxy skin
• Painfully cold part
suddenly stops hurting
28. Classifications of Frostbite
• First-degree
• Warm, swollen,
and tender
• Second-degree
• Blisters form.
• Enlarges over
several days.
• Third-degree
• Small blisters with
reddish-blue or
purplish fluid
• Red or blue skin
• Might not blanch
• Fourth-degree
• No blisters or
swelling.
• Part remains
numb, cold, and
purple.
29. Care for Frostbite (1 of 2)
• Get victim to warm area.
• Remove wet clothing and constricting items.
• Seek medical care.
• If affected part is partially thawed:
• Place part in warm water.
• Maintain water temperature.
• 20 to 40 minutes
• Give pain medication.
• Apply warm cloths to ear or facial injuries.
30. Care for Frostbite (2 of 2)
• After thawing:
• Treat the victim as a stretcher case.
• Protect area from contact with clothing and
bedding.
• Place dry gauze between toes and fingers.
• Slightly elevate the affected part.
• Apply aloe vera gel.
• Provide pain medication.
31. Hypothermia
• A life-threatening condition in which the
body’s core temperature falls below 95°F
• Body loses more heat than it produces.
• Heartbeat/breathing may be undetected
• Begin CPR immediately.
• Consider whenever victim’s behavior and
history and the weather conditions indicate
abnormal heat loss
32. Types of Exposure
• Acute
• Usually in
water
• 6 hours or less
• Subacute
• 6 to 24 hours
• Land or water
• Chronic
• Occurs on land
• Exceeds 24
hours
33. Hypothermia Symptoms
• Change in mental status
• Disorientation
• Apathy
• Changes in personality
• Shivering
• Cool abdomen
• Low core body temperature
34. Types of Hypothermia
• Mild to severe based on core body
temperature
• In severe cases, shivering stops.
• Do not start CPR if:
• Core body temperature is below 60°F.
• Chest is frozen.
• Submerged in water for more than 60 minutes.
• A lethal injury exists.
• Transport will be delayed.
• Rescuers are endangered.
35. Recognizing Mild Hypothermia
• Vigorous, uncontrolled shivering
• Decreased mental skills
• Slurred speech
• Difficulty using fingers or hands
• Staggers while walking
• Cool or cold skin on abdomen, chest, or back
• Core body temperature above 90°F
36. Care for Mild Hypothermia
• Get victim out of cold.
• Handle gently.
• Prevent heat loss.
• Cover the victim with a vapor barrier.
• Keep the victim horizontal.
• Call 9-1-1.
• Allow the victim to shiver.
• Give warm, sugary drinks.
37. Recognizing Severe
Hypothermia
• No shivering
• Ice cold and blue skin
• Stiff and rigid muscles
• Altered mental status
• Slow breathing and pulse
• Might appear dead.
• Core body temperature is below 90°F.
38. Care for Severe Hypothermia
• Get victim out of the cold.
• Handle gently.
• Prevent heat loss.
• Cover with vapor barrier.
• Keep victim horizontal.
• Call 9-1-1.
• When remote, warm by available heat.
39. Adding Heat
• Problems with rewarming:
• Warm water immersion requires a lot of
warm water and a bathtub.
• Body-to-body contact in insulated sleeping
bag is not better than shivering.
• No evidence that chemical heating pads
are capable of rewarming a hypothermic
victim.
40. Dehydration (1 of 2)
• Occurs because of unperceived fluid loss
combined with inadequate fluid intake.
• Cold weather: fluid lost through breath
• Drink even if not thirsty
• Inactive: drink two quarts of water daily
• Color and volume of urine indicate
hydration.
41. Dehydration (2 of 2)
• Unmelted snow and ice should not be
consumed for water.
• Irritates the mouth.
• Wastes body heat
• Lowers body temperature
• Be sure snow and ice are disinfected
before consumption.
