Ways to Beat the Heat
Jun 23rd, 2009
Needless to say, it is hot out there. Record-breaking hot. Below is a comprehensive, if not exhaustive, list of ways to stay safe during this time of extreme heat. Please pass them along to friends and neighbors.Heat Related Injuries
Slow down. Strenuous activities should be reduced or eliminated, or rescheduled to a cool time of day. Persons at risk, especially the elderly, should stay in the coolest place available out of the sun or in an air-conditioned room. Young people should avoid vigorous athletic activities during peak daylight hours. Coaches and teachers should enforce low stress activities for their athletes/students.
Dress for summer. Lightweight, light-colored, loose clothing reflects heat and sunlight, and helps your body maintain normal temperatures.
Drink plenty of water and other non-alcoholic fluids. Your body needs water to keep cool. Drink plenty of fluids even if you do not feel thirsty. Caffeinated beverages should be minimized in favor of water and sports drinks. (A good test of hydration is to make sure your urine is always clear in color.)
Fluid replacement – Unrestricted fluid intake is encouraged. Ideally, the rate of fluid replacement should approximate rate of sweat loss, which can be checked with daily weighing.
If a sports drink is not available, plain water is a good thirst quencher. However, ingesting water only will turn off the thirst mechanism prematurely thus reducing voluntary fluid intact. Sports drinks are the preferred beverage when athletes are working hard and sweating profusely. The sweeteners and flavor of the sports drink may encourage voluntary fluid intake. The carbohydrate in the sports drinks supplies energy to active muscles and the electrolytes help maintain fluid intake and fluid retention.
Do not drink alcoholic beverages. While they may feel as if they are cooling you off, they can worsen the problem.
Do not take salt tablets unless specified by a physician. Persons on salt-restrictive diets should consult a physician before increasing their salt intake.
Spend more time in air-conditioned places. Air-conditioning markedly reduces danger from heat. If you cannot afford an air-conditioner, spend some time each day during hot weather in an air-conditioned environment. Go to the Mall, churches or other cool places that are open to the public.
Don't get too much sun. Sunburn makes the job of heat dissipation that much more difficult. Always remember to use sun block (SPF>15) when outdoors for prolonged periods of time in the summer months.
Keep an eye on your neighbor! People at the extremes of age are most susceptible to heat injury. Check the elderly neighbor to make sure that they are staying cool and hydrated.
Heat stroke is a severe medical emergency. If a person is experiencing severe signs of exhaustion, it is important to move the victim to a cooler environment and reduce body temperature with ice or cool water. Summon emergency medical assistance or get the person to a hospital immediately.
Heat Illnesses
Heat illnesses are the result of elevated body temperatures due to an inability to dissipate the body's heat and/or a decreased fluid level. Always remember that mild heat illnesses have the potential of becoming severe life threatening emergencies if not treated properly
Heat Cramps
Heat cramps are a form of muscle cramp brought on by exertion and insufficient salt.
Heat Cramps Treatment
Replace salt and fluid (see Fluid Balance) and stretch the muscle (See Chapter 6 - Wilderness Travel & Camping: Stretching). Kneading and pounding the muscle is less effective than stretching and probably contributes to residual soreness.
Heat Syncope
Heat Syncope (fainting) is a mild form of heat illness which results from physical exertion in a hot environment. In an effort to increase heat loss, the skin blood vessels dilate to such an extent that blood flow to the brain is reduced, resulting in symptoms of faintness, dizziness, headache, increased pulse rate, restlessness, nausea, vomiting, and possibly even a brief loss of consciousness. Inadequate fluid replacement which leads to dehydration contributes significantly to this problem.
Heat Syncope Treatment
Heat Syncope should be treated as fainting (See Fainting). The person should lie or sit down, preferably in the shade or in a cool environment. Elevate the feet and give fluids, particularly those containing salt (commercial "rehydration" mix or ½ teaspoon salt and ½ teaspoon baking soda per quart/0.9 liter) (see Fluid Balance page 00). The patient should not engage in vigorous activity for at least the rest of that day. Only after s/he has completely restored his/her body fluids and salt and has a normal urinary output should exercise in a hot environment be resumed (and then cautiously).
Heat Exhaustion
This occurs when fluid losses from sweating and respiration are greater than internal fluid reserves (volume depletion). Heat Exhaustion is really a form of volume shock. The lack of fluid causes the body to constrict blood vessels especially in the periphery (arms and legs). To understand Heat Exhaustion think of a car with a radiator leak pulling a trailer up a mountain pass. There is not enough fluid in the system to cool off the engine so the car overheats. Adding fluid solves the problem. The signs and symptoms of Heat Exhaustion are:
Sweating
Skin - Pale, clammy (from peripheral vasoconstriction)
Pulse - Increased
Respirations - Increased
Temperature - normal or slightly elevated
Urine Output - Decreased
Patient feels weak, dizzy, thirsty, "sick," anxious
Nausea and vomiting (from decreased circulation in the stomach)
Heat Exhaustion Treatment
Victims of Heat Exhaustion must be properly re-hydrated and must be very careful about resuming physical activity (it is best to see a physician before doing so). Treatment is as described above for Heat Syncope, but the person should be more conservative about resuming physical activity to give the body a chance to recover. Have the person rest (lying down) in the shade. Replace fluid with a water/salt solution (commercial "rehydration" mix or ½ teaspoon salt and ½ teaspoon baking soda per quart/0.9 liter) (see Fluid Balance page 00). Drink slowly, drinking too much, too fast very often causes nausea and vomiting.
Evacuation usually is not necessary. Heat Exhaustion can become Heat Stroke if not properly treated (see Heat Stroke below). A victim of Heat Exhaustion should have be closely monitored to make sure that their temperature does not go above 103° F (39° C) If it does so, treat the person for Heat Stroke as described below.
Heat Stroke - Hyperthermia
Heat Stroke is one of the few life threatening medical emergencies. A victim can die within minutes if not properly treated. Heat Stroke is caused by an increase in the body's core temperature. Core temperatures over 105° (41° C) can lead to death. The rate of onset of Heat Stroke depends on the individual's fluid status. To understand Heat Stroke think of that same car pulling a trailer up a mountain pass on a hot day. This time the radiator has plenty of fluid, but the heat challenge of the engine combined with the external temperature is too much. The engine can't great rid of the heat fast enough and the engine overheats. There are two types of Heat Stroke-fluid depleted (slow onset) and fluid intact (fast onset).
Fluid depleted - The person has Heat Exhaustion due to fluid loss from sweating and/or inadequate fluid replacement, but continues to function in a heat challenge situation. Ultimately, the lack of fluid has minimized the body's active heat loss capabilities to such an extent that the internal core temperature begins to rise. Example: a cyclist on a hot day with limited water.
Fluid intact (fast onset) - The person is under an extreme heat challenge. The heat challenge overwhelms the body's active heat loss mechanisms even though the fluid level is sufficient. Example: a cyclist pushing hard on a 104° F day (40° C).
Signs & Symptoms of Heat Stroke
The key to identifying Heat Stroke is hot skin. Some victims may have hot, dry skin, others may have hot, wet skin because they have just moved from Heat Exhaustion to Heat Stroke.
Peripheral vasoconstriction (skin gets pale)
Pulse Rate - increased
Respiratory Rate - increased
Urine Output - decreased
Temperature - increased (may be over 105° F/41° C)
Skin - may be wet or dry, flushed
AVPU - Severe changes in mental status and motor/sensory changes, then the person may become comatose, possibility of seizures.
Pupils - may be dilated and unresponsive to light
Heat Stroke Treatment
Efforts to reduce body temperature must begin immediately! Move the patient (gently) to a cooler spot or shade the victim. Remove clothing. Pour water on the extremities and fan the person to increase air circulation and evaporation. Or cover the extremities with cool wet cloths and fan the patient. Immersion in cool (not cold) water is also useful. During cooling the extremities should be massaged vigorously to help propel the cooled blood back into the core.
After the temperature has been reduce to 102° F (39° C), active cooling should be reduced to avoid hypothermia (shivering produces more heat). The patient must be monitored closely to make sure that temperature does not begin to go up again.
Volume replacement - the victim will probably need fluid regardless of the type of onset.
Basic life support, CPR if needed.
Afterwards there can be serious medical problems. Prepare to evacuate your patient.