Ch 18: Thermal Injuries
In hot conditions, how many additional L of fluids do physically active individuals need daily to avoid dehydration?
4 to 10L
How many deaths a year does lightening cause?
54
How many oz of fluid should you consume during the activity?
7 to 10 oz every 10 to 20 min
What does normal core (oral) body temperature range from (degrees F)?
98.0 to 98.6 F
Over what percent humidity impairs evaporation?
Over 70%
What colors facilitate heat buildup?
Dark
Temperature-related health emergencies sometimes result in ______
Death
What can heatstroke result in if not treated correctly?
Death!
What is the number 2 cause of death due to weather phenomena? (What is number 1?)
#2 = lightening #1 = flooding
S&S of deep frostbite:
- Affected body part feels hard, solid, and cannot be depressed - Blisters appear in 12 to 36 hrs - Affected body part is cold, with pale, waxy skin - The painfully cold body part suddenly stops hurting
You should consume 17 to 20 oz of fluid how many hours before activity? You should consume an additional 7 to 10 oz how long before the activity?
2 to 3 hours; 10 to 20 min
What percent of body weight can individuals lose during exercise?
2% to 6%
Prevention of Hypothermia:
- Assess risk by learning to use a wind-chilled chart - Don't take long outdoor trips alone. Tell someone where you are going and when you expect to reach your destination - Learn to recognize early warning signs of hypothermia - Dress appropriately for cold weather (new synthetic materials move body moisture away from the skin while retaining body heat) - Make sure to remain hydrated and consume adequate calories to generate body heat (avoid using drugs such as alcohol)
Prescription Medications and Heatstroke
- Cold medications act like amphetamines and increase heat production - Antihistamines and anti-diarrhea medicines interfere with body cooling by reducing sweat production
Alcohol and Heatstroke
- Decreases cardiac output and can cause hyperthermia - Causes electrolyte disturbances in skeletal muscle - Causes dehydration
Factors that increase the risk of heat stroke:
- Drugs - Alcohol - Illness - Sickle Cell Trait - Prescription Medications
S&S of Dehydration
- Dry mouth - Thirst - Irritability or crankiness - Headache - Dizziness - Excessive fatigue - Reduced physical performance
FA for frostbite
- Get medical attention immediately - DO NOT attempt rewarming if medical attention is near; just protect area - If medical help is delayed, slow rewarming is necessary - Remove clothing/restricting items such as rings - Place in warm water (102-106 F)... but NOT boiling... just like warm bath water temp
Guidelines for Thunder and Lightening
- If thunder or lightening can be heard or seen, stop physical activity and seek protective shelter (in/out) immediately - If no shelter is available, find a ditch, ravine or valley, assume crouch position, place arms on legs and lower head. DO NOT LIE FLAT!! - Getting in a vehicle if one is available is okay - Allow 30 min to pass after the last sound of thunder or lightening strike before resuming activity
S&S of hypothermia:
- In mild cases: shivering, loss of motor function, speech slurring, confusion, and memory loss - In severe cases: lack of shivering, stiff muscles, blue skin, and decreased respiration and pulse. Body temp is below 90 F. (Individual may be semiconscious or unconscious)
Management of Heat Cramps
- Individual should immediately cease exercising - Give person fluids to consume, either water or commercially prepared sports drinks - Ice affected muscles - Have individual perform static stretching of involved muscles
Management of Heat Exhaustion
- Individual should immediately cease exercising - If individual is not nauseous, give fluids immediately, preferably cool water or sports drink - Move individual to cool location and place into a supine position with legs elevated 8 to 12 inches - Loosen person's clothing and cool with wet towels or ice packs - If individual is not fully recovered withing 30 minutes, seek medical attention *Do NOT allow individual to return to participation for remainder of the day!
S&S of Heat Exhaustion
- Moist, clammy skin and profuse sweating - General muscle fatigue and/or cramps - Nausea or related GI distress - Dizziness, and occasionally loss of consciousness - Severe thirst and headache - Increased respiratory rate and rapid pulse - Body temperature that ranges from 97 to 104 F
Management of Mild Hypothermia:
- Move person to a source of heat and out of the cold - Remove any wet clothing - Wrap in warm, dry clothing or blankets - Warm person with an electric blanket or hot packs placed around head and neck, armpits, groin, and chest - Avoid rewarming the extremities as doing so may result in vasodilation resulting in cooled blood returning to the core causing on "afterdrop" in temperature
Management of heatstroke:
- Need "heroic" measures to cool person immediately - If EMS personnel, AT, or physician is present, cool the athlete using cold-water immersion - If the above personnel are not on site, summon EMS immediately - Cool person following guidelines and move to a cool, humidity controlled location
What is body heat gained through?
- Radiation - through space - Conduction - through touch - Convection - through wind/water - Body metabolism
What is excess body heat lost through?
- Radiation, Conduction, Convection - Evaporation (through conversion of H2O, sweat, to gas on the skin surface)
Management of Dehydration
- Remove individual from participation and move him to a cool location - Rehydrate with water or sports drink, preferably one that is 50 to 59 F - If dehydration is minor (less than 2% body weight loss) and symptoms are relieved, individuals may return to participation - If symptoms persist, seek medical attention
S&S of Heat Cramps
- Severe cramping in arms or legs - Muscle cramps in the abdominal region - Profuse sweating
S&S of Heatstroke:
- Sweating may or may not be present - Hot, dry skin or clammy skin (sweating has stopped) - Mental confusion and possible loss of consciousness - GI distress, including nausea and vomiting - Severe motor disturbance and loss of coordination - Rapid and strong pulse (tachycardia) - Rectal temp higher than 104 F
Management of Severe Hypothermia
- Transport individual immediately to a health care facility - Prevent further heat loss by moving individual to a warm place and by gently removing cold wet clothing - Do NOT attempt to aggressively rewarm, just prevent against further heat loss - Monitor vital signs - potential for cardiac complications
How to prevent Exertional Heat Illness
- Utilize a weight chart to determine if an individual is consuming enough fluids and regaining weight loss in previous exercise sessions - Avoid water intoxication (hyponatremia) - be sure electrolytes are in fluid for long duration events - Avoid heavy exertion during times of extreme heat (above 95 F) and humidity - Individual should avoid wearing restrictive clothing/equipment - Improved fitness levels have a positive effect on one's ability to function in extreme conditions
S&S of superficial frostbite:
- White or grayish-yellow skin color - Pain may occur initially and later subside - Affected part feels very cold and numb - Tingling, stinging, or aching sensation - Skin surface feels hard and crusty - Underlying tissue feels soft when depressed gently and firmly
What to do while waiting on EMS in the case of a heatstroke victim?
- Wrap person in wet towels or sheets, and place ice bags on neck, head, groin, or under armpits - Treat for shock and monitor body temp and vitals. Do not allow body temp to drop below 102 F - Keep person in semi-seated position, so "hot" blood does not go to brain - Transport to hospital ASAP
What are the chances of being struck by lightening?
1 in 10,000
For every ______ lbs of weight loss, the individual should consume ______ oz of fluid
1 lb; 24 oz
How long does acclimatization take?
1 to 6 weeks
As a result of proper acclimatization, how much sweat per hour can the sweating mechanism yield?
1.5 to 3.0 liters of sweat/hr, as much as 12 L/day
What percent of thermal situations are preventable?
100%
What facilitates hypothermia (even if the temperature is well above freezing)?
A combination of wind and moisture
What is considered minimal dehydration?
A loss of less than 2% of body weight
What is acclimatization?
A process in which the body adjusts to continuous and significant climate change
Recent evidence suggests coaches follow a 14 day plan for ____________ and _____________
Acclimation and fitness
What is damage in frostbite caused by?
Actual freezing of tissues as well as lack of blood (O2) supply to the tissues as a result of clotting
Who might take longer to acclimatize?
Adolescents, obese individuals, and those with certain metabolic disorders
During outdoor activities in freezing temps, individuals need to do what?
Be vigalent for early warning signs of frostbite
Why won't icing affected muscles solve the problem (of heat cramps)?
Because it is an internal issue... but it will help to alleviate pain
How does the body cool itself?
By sweating and through the evaporation of sweat.
What is heat a byproduct of and how can it be accumulated? What does it create?
Byproduct of metabolism and can be accumulated from a hot environment. This creates a "double attack" on the body
Illness and Heatstroke
Can increase risk for heatstroke especially when fever is present
FA for frostnip
Cover and warm with rubbing or warm air
Minimal dehydration generally (does or does not) affect health or performance
Does not
Drugs and Heatstroke
Drugs such as cocaine or speed tend to increase physical activity and reduces the awareness of fatigue
When should those supervising outdoor activities reduce exercise demands?
During periods of high humidity and temperature
What is external heatstroke usually related to?
Excess body fluid losses combined with inadequate evaporative cooling (heat-regulating mechanisms shut down)
Sickle Cell Trait and Heatstroke
Exposure to heat and exertion can cause sickle cell crisis and death
Who is at risk for developing hypothermia? Why?
Extremely lean individuals because they have little insulating body fat
The more physically fit the individual, the __________ the acclimatization
Faster
S&S of frostbite:
Feeling of burning and pain, followed by progressive loss of sensation
What conditions usually involve the nose, ears, fingers, and feet?
Frostbite and frostnip
What does heat exhaustion cause?
Generalized fatigue during exercise when excessive body fluid losses occur
What can heat exhaustion be a precursor to?
Heat stroke (a true medical emergency)
What do coaches/trainers/health professionals need to be aware of?
High temps, high humidity, and body types (fat produces heat)
Where do heat cramps generally develop?
In the muscles being exercised
Fluid needs ______ as the rate of sweating increases
Increase
What does exercise do to metabolic rate and body temp?
Increases metabolic rate and elevates body temp to 104 F
Who does external heatstroke occur in?
Individuals exercising in hot, humid conditions
What effect does high humidity have on evaporation?
Less ability the surrounding air has to absorb fluid (sweat) from the skin surface
Frostnip
Less severe and involves only outer skin layers
Should you rely on thunder as a forewarning of lightening?
NO
In what sort of individuals does classic heatstroke occur?
Obese, the chronically ill or elderly, or diabetes
What climate is evaporation most efficient during exercise?
On dry land
S&S of frostnip
Red and windburned skin
What must an individual do in order to sweat and evaporate heat from the body?
Remain hydrated
Types of frostbite:
Superficial and deep
What areas of the body should you work to cool when treating heatstroke?
The head and torso (major organs)
What is thermoregulation controlled primarily by?
The hyopthalamus in the brain
How many deaths (from temperature-related injuries) could be prevented if the environment is taken into consideration before allowing an even to begin?
The majority, if not all of them
What does hypothermia involve?
The rapid loss of body heat, resulting in total body cooling
How much lightening is not accompanied by thunder?
Up to 40%
Excess heat must be eliminated to maintain what?
Vital body functions
What are heat cramps probably related to?
Water and mineral loss that result from sweating
When does severe damage occur for frostbite?
When frostbitten tissue is thawed and refrozen
When can evaporation be reduced?
When humidity is high
When does heat stroke occur?
When the body is unable to cool itself & a radical elevation in body temp occurs exceeding 104 F
When does mild hypothermia begin?
When the core body temp drops to 95 F
When is heat loss negated?
When there is extreme humidity and sweat cannot evaporate
When does frostbite occur?
When tissues freeze after excessive exposure to cold
