Heat/Cold Stress

HEAT STRESS:
Heat Stress is the potentially dangerous condition that occurs when the body is unable to regulate its core temperature. There are three main classes of heat stress disorders.

Heat cramps are painful and severe muscle spasms, primarily in the extremities and abdominal wall. Victims may experience profuse sweating, and dizziness. Treat by moving victim to a cool place and begin re-hydration process. Do not keep the victim sedentary in direct heat. Heat exhaustion is peripheral vascular due to excessive water and salt depletion. It is caused by failure to replenish fluids lost in perspiration. Symptoms include sweaty and pale or flushed, cool, clammy skin; fatigue; nausea; headache and possible dizziness, nausea and/or vomiting.

Heat exhaustion victims should be placed in a cool place; loosened clothes, applying cool compress, slowly reintroducing fluids and monitoring them for symptoms of shock. Seek advanced medical assistance immediately for further assessment and treatment.

HEAT STROKE IS A MEDICAL EMERGENCY THAT REQUIRES ADVANCED TREATMENT WITHOUT DELAY! It is the result of the collapse of the thermal regulatory mechanism; the ability for the body to cool itself. Body temperatures rise to critical levels of 104° F to 108° F. Symptoms include the stopping of sweating; hot, dry skin; red or molten skin; core body temp > 104° F; confusion; loss of consciousness; and convulsions. Treat by calling 911 emergency medical services, moving the victim to a cool area while waiting for transportation to hospital, using cool water to soak clothes and body, and fanning person. Do not give fluids if the victim is unconscious.

Preventative Measures for Heat Stress:
Drink moderate amounts of water frequently.
Wear sunscreen with an SPF level of 15 or higher recommended.
Covers shall be worn while outdoors in accordance with uniform regulations.
Do not rely on electro replenishment fluids such as Gatorade as a sole source of hydration Caffeinated Energy drinks are discouraged during training. For more information on energy drinks.

COLD STRESS:
Frost nip, frost bite, and hypothermia are medical conditions associated with cold stress.

Frost nip is the first stage of frost bite when only the surface skin is frozen. Frost nip begins with itching pain. The skin then blanches and eventually the area becomes numb. Treat by moving victim to a warmer area and follow the treatment recommendations for frostbite.

Frost bite is damage to tissues from freezing due to formation of ice crystals within cells, rupturing the cells, and leading to cell death. Frost bite occurs when temperatures are below freezing. Symptoms include a burning sensation at first, whitened areas of skin, blistering, and the affected part may be cold, numb, and tingling. Treat by covering the frozen part, providing extra clothing and blankets, placing the affected part in warm water or covering with warm packs. Discontinue warming when part becomes flushed and swollen. Do not place pressure dressings on the affected area, or rub body part. Give sweet, warm fluids. Do not use heating device on part. Obtain medical assistance immediately.

Hypothermia is a reduction in core body temperature that occurs when exposure to cold causes a person’s body to lose heat faster than it can be replaced. Symptoms include pain in extremities, uncontrollable shivering, reduced core temperature, cool skin, rigid muscles, slower heart rate, weakened pulse, low blood pressure, slow irregular breathing, slurred speech, drowsiness, incoherence, lack of coordination, diminished dexterity, and diminished judgment. Treat by moving victim from the cold source. Remove wet clothing and get into dry clothing. Wrap victim with a blanket. Pack neck, groin and armpits with warm packs or warm towels. Give sweet, warm drinks. Keep the victim awake. And transport them to a medical facility immediately.

Signs and symptoms of Hypothermia:
Mild hypothermia (98-90° F): Shivering, lack of coordination, stumbling, fumbling hands, slurred speech, memory loss, pale, cold skin.
Moderate hypothermia (90-86° F): Shivering stops, unable to walk or stand, confused and irrational.
Severe hypothermia (86-78° F): Severe muscle stiffness, very sleepy or unconscious, ice cold skin. Death is eminent.

Preventative Measures for Cold Stress:
Drink moderate amounts of water frequently.
Avoid alcohol, certain medications and smoking to mitigate risk.
Wear appropriate clothing:
  Cotton looses insulation when wet
  Wool retains insulation when wet
  Wear layers 
  Outer layer to deflect wind,
  Middle layer (down, wool) to absorb sweat and provide insulation even when wet,
  Inner layer (cotton, synthetic weave) allow insulation/ventilation
  Wear cover/hat (60% of heat is lost though head)
  Wear insulated boots and full fingered gloves
  Loose clothing allows better ventilation