hot And Cold Flashcards
(35 cards)
What are the four mechanisms of heat loss?
Radiation, convection, conduction, and evaporation
- Question: Describe how radiation works as a method of heat loss.
Answer: This refers to heat loss through infrared rays. No medium is required for this method of heat transfer.
- Question: What is convection?
Answer: Convection is heat loss through the movement of air or water molecules across the skin. For example, a fan can promote heat loss through convection.
Question: How does conduction work to cool the body down?
Answer: Conduction is heat loss via direct contact with a cooler surface. For example, sitting on a cold metal bench would cause the body to lose heat via conduction.
. Question: Explain how the body can lose heat through evaporation.
Answer: Evaporation involves the conversion of water (sweat) to a gas, which results in heat loss. This is the primary method of heat loss during exercise.
What are some mild forms of heat illness?
Heat edema, heat rash, heat syncope, and heat cramps are considered mild forms of heat illness.
What are the symptoms of heat edema?
Heat edema occurs when the body tries to cool itself down through peripheral vasodilation. This causes fluid to pool in the extremities, leading to soft tissue swelling in the hands and feet.
How is heat edema treated?
- Elevating the hands/feet
- Using compressive stockings
- Hydration and salt intake
It is important to avoid diuretics. Heat edema will typically resolve within 7-14 days.
What is heat rash?
Heat rash, also called sweat rash, miliaria rubra, or prickly heat, occurs when sweat glands get clogged, causing sweat to leak into the epidermis or dermis. It results in a blister-like rash.
What are some treatment options for heat rash?
- Cool the skin and prevent sweating
- Wear loose and light clothing
- Shower in cool water and let the skin air dry
- Use a mild anti-inflammatory lotion
Heat rash will usually clear up within a few weeks.
What is heat syncope and what causes it?
Heat syncope involves fainting due to orthostatic hypotension, which is caused by peripheral vasodilation and venous pooling.
How should heat syncope be treated?
- Have the person lie down in a supine position in a cool location
- Elevate the legs
- Hydrate
- Check for injuries
- Evaluate the cardiovascular and central nervous systems for serious causes of syncope
What causes heat cramps?
The exact cause of heat cramps is unknown, but it is thought to be related to electrolyte depletion or sodium loss.
What is the best way to treat heat cramps?
- Removal from activity
- Hydration (e.g., sport drinks)
- Light stretching or massage
- Cooling with ice
If the cramps do not subside within an hour, seek medical help.
What are the symptoms of heat exhaustion?
- Elevated core temperature between 37°C–40°C
- Malaise, fatigue, dizziness, heavy sweating, headache, vomiting, weakness, cold or clammy skin
- Normal mental and neurological status
- Possible tachycardia or hypotension
How can you prevent heat exhaustion from progressing to heat stroke?
To prevent heat exhaustion from progressing to heat stroke, it is important to check the person’s core temperature using a rectal thermometer.
How should heat exhaustion be treated?
- Removing the person from the heat
- Having them lie down in a supine position with their legs elevated
- Cooling the body down
- Hydrating with cool fluids, such as sport drinks
- Monitoring core temperature
If the person does not feel better within one hour, seek medical help.
What is the defining symptom of heat stroke?
Heat stroke is defined by an elevated core temperature of 40°C or greater.
Other than a high core temperature, what are some other signs and symptoms of heat stroke?
Heat stroke may involve central nervous system disturbances such as:
* Irritability
* Ataxia
* Confusion
* Coma
* Seizures
What are the two types of heat stroke?
Classic heat stroke is caused by environmental heat waves while exertional heat stroke is caused by intrinsic heat production.
What is the most important step in treating heat stroke?
Answer: When treating heat stroke, the most important step is to reduce heat as quickly as possible. The goal is to lower the person’s core body temperature to less than 38.9°C within 30 minutes.
What is the best method for cooling someone down who has heat stroke?
Answer: Cold water immersion (CWI) is the best method for cooling someone down who has heat stroke. Ideally, the water should be between 1.7°C–15°C. It is important to monitor the person’s core body temperature every 3-5 minutes during cooling and remove them from the water when their temperature reaches 38.9°C to prevent overcooling.
. Question: What are some complications that may arise from heat stroke?
Answer: Potential complications of heat stroke include:
* Seizure
* Hypotension
* Arrhythmias
* Damage of vital organs
* Rhabdomyolysis
. Question: What is WBGT and what factors does it consider?
Answer: WBGT (Wet Bulb Globe Temperature) measures heat stress in direct sunlight. It takes into account the following factors: temperature, humidity, wind speed, sun angle, and cloud cover.
