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Cold-Related Emergencies

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Presentation on theme: "Cold-Related Emergencies"— Presentation transcript:

1 Cold-Related Emergencies
Chapter 20 Cold-Related Emergencies

2 Cold-Related Emergencies
Normal body temperature is 98.6°F. Body loses heat when surrounded by air or water that is cooler than the body. Body temperature falls Cold injuries can result.

3 How Cold Affects the Body (1 of 2)
Biologic defense mechanisms protect body Vasoconstriction Tightening of blood vessels Can cause discomfort, numbness, loss of dexterity, cold injuries Shivering produces body heat. Stops when core temperature falls too low or when there is no fuel.

4 How Cold Affects the Body (2 of 2)
Physical activity produces heat. Heat loss after exertion if clothes are wet Proper hydration and nutrition help prevent cold injuries. The colder the temperature, the greater the potential of body heat loss. Physical changes from cold exposure can impair ability to perform manual tasks.

5 Heat Loss From the Body (1 of 2)
Body temperature maintained by balance of heat production and loss Shivering rapidly consumes calories. Heat loss occurs primarily through skin.

6 Heat Loss From the Body (2 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 Radiation Heat given off to cooler air Primary method of heat loss

7 Susceptibility to Cold Injury
Physically unfit Dehydration Very lean people Elderly Alcohol, caffeine Smoking, chewing tobacco Inadequate nutrition, illness, injury Previous cold injury

8 Effects of Altitude Temperature, windchill are considerations
Air temperature drops 3.6°F every 1,000 feet. Winds more severe More susceptible to frostbite above 8,000 feet

9 Effects of Water Conducts heat away from body faster than air.
Body heat loss occurs 25 times faster with wet clothing. Plunging into cold water can cause irregular heartbeat, gasping, hyperventilation. These can cause water inhalation, heart failure, drowning.

10 Effects of Wind Increases potential for body heat loss
Windchill index integrates wind speed and air temperature. Helps estimate risk of cold injury. Artificial wind can increase heat loss.

11 Effects of Metal and Liquid Fuels
Can conduct heat away from skin rapidly. Contact can cause almost instantaneous freezing. Must use great care when handling.

12 Minimizing Effects of Cold on the Body
Adequate clothing is key Layered clothing helps maintain proper body temperature. Undergarments Should wick away perspiration Middle layer Synthetic pile, fleece, or wool Outer layer Waterproof, wind resistant, breathable, with zipper

13 Nonfreezing Cold Injuries
Can occur when conditions are cold and wet, hands and feet cannot be kept warm and dry Chilblain Trench foot

14 Chilblain Painful, but causes little or no permanent damage
Can develop in 3 to 6 hours if exposed to cold and moisture

15 Recognizing Chilblain
Swollen skin Tender, hot to touch, itchy Blisters Aching, prickly sensation Numbness

16 Care for Chilblain Get victim out of cold.

17 Trench Foot Serious injury, also called immersion foot
Develops when feet exposed to moisture and cold for 12 hours or longer Moisture softens skin, tissue loss and infection occur Crippling injury can occur

18 Recognizing Trench Foot
Itching, numbness, tingling pain Swollen feet, pale skin cold to touch Red, bluish blotches on skin Sometimes open weeping, bleeding

19 Care for Trench Foot Dry the skin. Rewarm foot gradually.
Cleanse weeping areas with mild soap and water, apply breathable dressings.

20 Freezing Cold Injuries
Occur when air temperature is below freezing (32°F) Frostnip Freezing is limited to skin surface Frostbite Freezing occurs deeper in skin Frostbite more common in military, mountain climbers, explorers.

21 Frostnip Water freezes on skin surface
Serious — could signal impending frostbite

22 Recognizing Frostnip Red, swollen skin Painful
Dry, cracked, sensitive skin from repeated frostnip to same spot

23 Care for Frostnip Gently warm affected area.
Place against warm body part. Blow warm air on area. After, area can become red and tingling. Do not rub.

24 Frostbite Occurs when temperatures drop below freezing
Tissue can actually freeze Blood supply obstructed Affects feet, hands, ears, nose Most severe consequence = gangrene (dead tissue)

25 Recognizing Frostbite (1 of 2)
White, waxy, or grayish yellow skin Cold and numb Tingling, stinging, aching Stiff or crusty surface, soft underneath Deep frostbite: Cold, hard, solid Blistering Cold, pale, waxy skin Pain stops

26 Recognizing Frostbite (2 of 2)
First-degree Warm, swollen, tender Second-degree Blisters minutes to hours after thawing, enlarge over several days Third-degree Small blisters, reddish blue/purplish fluid Fourth-degree No blisters, no swelling Numb, cold, white to dark purple

27 Care for Frostbite (1 of 2)
Get victim to warm area. Remove wet clothing. Remove items that could impair circulation. Seek medical care. If affected part is partially thawed or victim is remote: Place part in warm water. Add warm water to maintain water temperature. Ear or facial injuries: apply warm, moist cloths.

28 Care for Frostbite (2 of 2)
After thawing: Place on stretcher if feet affected. Protect area from contact with clothing, bedding. Place dry dressings between toes and fingers. Slightly elevate to reduce pain and swelling. Apply aloe vera gel. Provide aspirin (adults), or ibuprofen, or acetaminophen.

29 Hypothermia (1 of 3) Life-threatening condition when core temperature falls below 95°F Can occur even when temperature is above freezing, if windy, wet, or person is inactive Can occur year round Death results if untreated Occurs rapidly during cold water immersion

30 Hypothermia (2 of 3) Heartbeat, breathing, response to pain may not be detectable Victim can still be alive. Check circulation for seconds. Start CPR immediately if immersion occurred. Handle gently. Must be evaluated by physician.

31 Hypothermia (3 of 3) Many different people susceptible.
Consider when behavior, history, and weather conditions indicate heat loss. More likely if behavior is strange and victim was shivering. Alcohol, medications can contribute Very old, very young, and less fit are more susceptible

32 Types of Exposure Acute Heat loss occurs rapidly (6 hours or less)
Usually in water Subacute Heat loss over 6-24 hours Land or water Chronic Long-term cooling greater than 24 hours Occurs on land

33 Recognizing Hypothermia
Suspect in anyone with temperature less than 95°F. Change in mental status: Disorientation, apathy, changes in personality Shivering Cool abdomen Low core body temperature (rectal)

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 less than 60°F Chest is frozen. Submerged more than 60 minutes Lethal injury Transport delayed Rescuers endangered

35 Recognizing Mild Hypothermia
Vigorous, uncontrollable shivering Grumbling, mumbling, fumbling, stumbling 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. Replace wet clothing with dry clothing. Cover head. Cover with vapor barrier. Keep victim horizontal. Do not raise legs. Do not let victim walk or exercise. Call Allow shivering.

37 Recognizing Severe Hypothermia
No shivering Ice cold, blue skin Stiff, rigid muscles Altered mental status, not alert Slow breathing and pulse Victim might appear dead Core body temperature below 90°F

38 Care for Severe Hypothermia
Get victim out of cold. Handle gently. Replace wet clothing with dry clothing. Cover head. Cover with vapor barrier. Keep victim horizontal. Do not raise legs. Do not let victim walk or exercise. Call When remote, warm by any available heat source.

39 Adding Heat Problems with rewarming:
Warm water immersion requires a lot of warm water and a bathtub. Hot baths can cause cardiac arrest. Body-to-body contact in insulated sleeping bag is ineffective. Use body-to-body rewarming only when delayed care or other methods unavailable. Chemical heating pads are not effective.

40 Dehydration In cold weather, fluid is lost through exhaled breath.
Color and volume of urine indicate hydration. Unmelted snow and ice should not be consumed; can lower body temperature. If snow, ice are only available sources of water, melt before consuming. Melted snow, ice should be disinfected before drinking.


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