Probably the most common emergency weíll see as survivalists is some type of environmental emergency, such as hypothermia or hyperthermia. Being outdoors, training, or doing other vigorous activities can lead to temperature control problems within the body.
Hypothermia is caused from prolonged exposure to cold. It can occur in Southern climates as easily as Northern. Although the elderly and the young are usually the most affected, anyone can suffer from it. Hyperthermia can strike anyone who is outdoors in hot weather or working in a hot confined area. These conditions arenít selective of whom they strike, but fortunately, many steps can be taken to prevent them.
There are several methods of cool or heat transfer. Naturally, heat transfers to cold, but that can be altered. Conduction is when two objects of different temperatures touch. The warmer object will transfer heat to the cooler object. This can work in lowering or raising body temperature. If a person is hot, sitting on a cold rock will lower the body temperature. If a person is cold, body to body heating will raise their temperature. This technique will be discussed in depth later. Convection must have air currents to work. Wind blowing, a ceiling fan, using a strong piece of paper or cardboard to manually fan someone are examples. The air carries the heat away from the source. Radiation is a heating method and is as simple as the sunshine, or a woodstove emitting heat. Evaporation is a cooling measure and takes place when sweat or water evaporates off of the skin. Itís not the act of sweating that cools; itís the evaporation of the sweat. The last method of cooling is breathing. Inhaling cold air can cool the body. When the body temperature begins to fall, inhaling cold air hastens the cooling process. Usually the heating or cooling process is a combination of these methods and if you understand them you can better prevent or treat these types of emergencies.
Hypothermia can be generalized or specific. Generalized is when the core body temperature, which is normally 98.6 degrees F, drops below 90 degrees F. This condition affects the entire body and if left untreated will result in death. It can be caused by prolonged exposure to cold climate, submersion in water, shock, hypoglycemia, burns, and closed head injuries. In early stages, when the core temp is between 96-99 degF, shivering will occur. Next, when the core temp is between 91-95 degF, there will be intense shivering, numbness in fingers and toes, the skin will appear bright red and chapped, and there may be difficulty speaking. The vital signs will increase in the bodies attempt to compensate for temperature. When the temp drops to 86-90 degF the shivering decreases or stops and the muscles become rigid. Coordination is affected, movements become jerky and erratic. Mentation is decreased, comprehension less, memory failing. At 81-85 degF, the patient has become irrational and stuporous. Muscular rigidity continues and may worsen. Pulse rate begins to slow and cardiac arrythmias may develop. Other vital signs will slow down as the body stops trying to fix itself. This is called decompensation. At 78-80 degF the patient becomes unconscious and doesnít respond to verbal or painful stimuli. Most reflexes will not respond. Respiration may be extremely slow or absent, and the pulse rate will be slow and irregular. Cardiac arrest is eminent. Specified cold injuries are usually called frostbite. This is when certain body parts, usually ears, nose, cheeks, chin, and extremities actually form ice crystals in the tissues. Smoking or use of any other tobacco, can exacerbate frostbite because it causes vasoconstriction. In early stages the skin will appear white and waxy, then as it progresses will turn mottled (uneven colored), then grayish-yellow, then finally, grayish-blue. General hypothermia will almost always be present with frostbite.
Treatment for hypothermia can be done on two levels, basic and advanced. As soon as a patient is found suffering from hypothermia, establish baseline vital signs, including mentation, and core temperature (best taken rectally if possible). Initially employ passive warming techniques by removing all clothing and drying patient off completely. Wrap patient in warm dry blankets. Try to raise the temperature of the ambient air (fireplace, woodstove, etc.). Another method of passive warming, mentioned earlier is body to body heating. With this method, the rescuer also removes his or her clothing and lays their naked body against the naked body of the patient and warms them with their body heat. The two people then wrap blankets around each other. In any warming remember to insulate the patient from the ground or the efforts to warm will be fruitless. Body to body warming is the most affective method of warming without employing active warming measures. In more severe cases, active warming will be necessary. Active warming utilizes all of the above measures but also includes starting an IV and running warmed IV fluids into the patient. This must be done slowly in more severe cases. If a severely hypothermic person is rewarmed to quickly there is a possibility of cardiac arrest. Warming must be done slowly with careful monitoring of the patientís vital signs.
Treating frostbite is similar, because the patient will also be suffering from hypothermia. The big difference is how to treat the frostbitten areas. In any situation oxygen should be administered if it is available, but if it isnít do the best you can with what youíve got. Once again do not allow the patient to use any type of tobacco products, due to vasoconstriction. Active rewarming of a frostbitten area is tricky and must be done carefully to prevent further damage to the area. First find a container in which the entire affected area will fit WITHOUT touching the sides or bottom. Medium sized trashcans work nicely. If you cant find something use a trash bag supported with a crate or box. Then heat water between 100 degF and 105 degF. You should be able to put your fingers into the water without discomfort. Next, fill the container with the heated water and prepare the injured part buy removing clothing, jewelry, bands, straps, etc. Fully immerse the part in the heated water. DO NOT allow the injured area to touch the sides or bottom of the container. Do not place any pressure on the affected area and do not rub or massage the affected area. Continuously stir the water with a spoon or other clean utensil, without touching the part (actually its stirring the top of the water). When the water cools below 100 degF remove the injured part, and then add more warmed water until it reaches 100 degF to 105 degF. Reimmerse the entire area again. The patient may complain of moderate to severe pain. This is usually a good indication of successful warming. Keep repeating this procedure until the area turns to a red or purple/blue color. Gently dry the area without rubbing, only patting. Next apply a dry sterile dressing to the area, if the area is a hand or foot, place sterile dressings between the fingers or toes before wrapping it completely. Now gently cover the area with covers, but once again, no pressure can be placed on the area. Itís best to build some type of frame (can be done with pillows) around the area. Keep the patient at rest. Donít allow them to walk if it was a lower extremity that was frozen. Keep the patientís whole body warm. Continue to monitor the patientís condition and vital signs. Reassess the affected area often and check for pulses below or on the area. Do not allow the patient to be re-exposed to the cold and especially do not let the injured area become refrozen. Slightly elevate the injured area to prevent edema (swelling), but continue good circulation (about six inches is adequate).
The next environmental emergency is Hyperthermia, more commonly known as heat cramps heat exhaustion, and heat stroke. A person exposed to high temperatures for prolonged periods will have excessive sweating and can lose up to one liter of fluid an hour. When high temperature is combined with high humidity, itís harder for the body to cool itself. The sweat doesnít evaporate because the air is already saturated with water. There are other conditions such as age, heart disease, obesity, fatigue, diabetes, etc, that can increase the possibility of heat related problems.
Heat cramps is the least serious, but none the less painful, of the three types of heat related emergencies. The patient will have moist, pale, normal to cool skin. They will be sweating profusely, and very thirsty, drinking a lot of water. As they drink the water to rehydrate, they lose essential salts (electrolytes) from the body. This causes painful muscle cramps that can occur in any muscle, but most often in the legs.
Heat exhaustion is the next step up and is a mild form of hypovolemic shock usually seen in firefighters, construction workers, or anyone who does strenuous outdoor work. The patient will have pale, normal to cool skin, and the skin will be moist. They will have weakness and/or dizziness and possibly faintness. The breathing will be rapid and shallow, the pulse weak. The treatment for both of the above conditions is to remove the patient from the hot environment into a cool area. If oxygen is available, administer at 10-15 liters per minute with a non-rebreather mask. Loosen or remove clothing to aid in cooling. Fan the patient but watch for shivering. Lay patient on his back with feet slightly elevated (about 12 inches), called Trendellenburg. If patient is conscious, give him small amounts of water or electrolyte solution (Gatorade or Powerade) by mouth. Have them sip it slowly to prevent vomiting.
Heat stroke is the most serious of heat emergencies and can lead to many other problems. The skin will be red and feel hot to the touch. If the patient is still sweating itís a good sign, but most often with heat stroke, the patient has stopped sweating. Without sweat the body cannot cool itself. The breathing will be rapid and shallow, pulse full and rapid. There will be generalized weakness and possibly decreased mentation. The pupils will be dilated. If cooling isnít started soon, seizures are eminent. Treatment is the same as above, in addition to active cooling. Place cool packs to the back of the neck, under the armpits, and in the groin area. These are the areas where major arteries are close to the surface and where heat collects. Keep the skin wet by applying water with sponges or wet towels. IV access with Lactated Ringers solution is necessary for rehydration. The fluids may be cool, but not cold. Do not submerge the patient in an icebath (too extreme) or rub alcohol on the skin (ineffective). Do not take the patient from the heat stroke to hypothermia.
Ways to avoid heat related emergencies: Drink plenty of water or electrolyte solution. Take breaks often and rest in the shade or other cool spot. If feeling like you are getting too hot stop the activity and place a cool cloth on back of neck.
These are the situations that will be very common, but are often overlooked as medical problems. Hopefully with this information everyone will be aware of them and know how to treat them should they occur.
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