Heat Injuries

Heat injuries are environmental injuries that may result when a soldier is exposed to extreme heat, such as from the sun or from high temperatures. Prevention depends on availability and consumption of adequate amounts of water. Prevention also depends on proper clothing and appropriate activity levels. Acclimatization and protection from undue heat exposure are also very important. Identification of high risk personnel (basic trainees, troops with previous history of heat injury, and overweight soldiers) helps both the leadership and the individual prevent and cope with climatic conditions. Instruction on living and working in hot climates also contributes toward prevention.

Salt tablets should not be used in the prevention of heat injury. Usually, eating field
rations or liberal salting of the garrison diet will provide enough salt to replace what is
lost through sweating in hot weather.

a. Diet. A balanced diet usually provides enough salt even in hot weather. But when people are on reducing or other diets, salt may need to come from other sources. DO NOT use salt tablets to supplement a diet. Anyone on a special diet (for whatever purpose) should obtain professional help to work out a properly balanced diet.

b. Clothing

(1) The type and amount of clothing and equipment a soldier wears and the way he wears it also affect the body and its adjustment to the environment. Clothing protects the body from radiant heat. However, excessive or tight-fitting clothing, web equipment, and packs reduce ventilation needed to cool the body. During halts, rest stops, and other periods when such items are not needed, they should be removed, mission permitting.

(2) The individual protective equipment (IPE) protects the soldier from chemical and biological agents. The equipment provides a barrier between him and a toxic environment. However, a serious problem associated with the chemical overgarment is heat stress. The body normally maintains a heat balance, but when the overgarment is worn the body sometimes does not function properly. Overheating may occur rapidly. Therefore, strict adherence to mission oriented protective posture (MOPP) levels directed by your commander is important. This will keep those heat related injuries caused by wearing the IPE to a minimum. See FM 3-4 for further information on MOPP.

c. Prevention. The ideal fluid replacement is water. The availability of sufficient water during work or training in hot weather is very important. The body, which depends on water to help cool itself, can lose more than a quart of water per hour through sweat. Lost fluids must be replaced quickly. Therefore, during these work or training periods, you should drink at least one canteen full of water every hour. In extremely hot climates or extreme temperatures, drink at least a full canteen of water every half hour, if possible. In such hot climates, the body depends mainly upon sweating to keep it cool, and water intake must be maintained to allow sweating to continue. Also, keep in mind that a person who has suffered one heat injury is likely to suffer another. Before a heat injury casualty returns to work, he should have recovered well enough not to risk a recurrence. Other conditions which may increase heat stress and cause heat injury include infections, fever, recent illness or injury, overweight, dehydration, exertion, fatigue, heavy meals, and alcohol. In all this, note that salt tablets should not be used as a preventive measure.

d. Categories. Heat injury can be divided into three categories: heat cramps, heat exhaustion, and heatstroke.

e. First Aid. Recognize and give first aid for heat injuries.

Casualty should be continually monitored for development of conditions which may
require the performance of necessary basic lifesaving measures, such as: clearing the
airway performing mouth-to-mouth resuscitation preventing shock, and/or bleeding
control.

(1) Check the casualty for signs and symptoms of heat cramps (081-831-1008). Signs/Symptoms. Heat cramps are caused by a imbalance of chemicals (called electrolytes) in the body as a result of excessive sweating. This condition causes the casualty to exhibit: o Muscle cramps in the extremities (arms and legs). o Muscle cramps of the abdomen. o Heavy (excessive) sweating (wet skin). o Thirst. Treatment. o Move the casualty to a cool or shady area (or improvise shade). o Loosen his clothing (if not in a chemical environment). o Have him slowly drink at least one canteen full of cool water. o Seek medical aid should cramps continue. WARNING DO NOT loosen the casualty's clothing if in a chemical environment.

(2) Check the casualty for signs and symptoms of heat exhaustion (081-831-1008). Signs/Symptoms which occur often. Heat exhaustion is caused by loss of water through sweating without adequate fluid replacement It can occur in an otherwise fit individual who is involved in tremendous physical exertion in any hot environment. The signs and symptoms are similar to those which develop when a person goes into a state of shock. o Heavy (excessive) sweating with pale, moist, o Headache. o Weakness. o Dizziness. o Loss of appetite. Signs/Symptoms which occur sometimes. o Heat cramps. o Nausea--with or without vomiting. o Urge to defecate. o Chills (gooseflesh). o Rapid breathing. o Tingling of hands and/or feet. o Confusion. Treatment. o Move the casualty to a cool or shady area (or improvise shade). o Loosen or remove his clothing and boots (unless in a chemical environment). Pour water on him and fan him (unless in a chemical environment). o Have him slowly drink at least one canteen full of cool water. o Elevate his legs. o If possible, the casualty should not participate in strenuous activity for the remainder of the day. o Monitor the casualty until the symptoms are gone, or medical aid arrives.

(3) Check the casualty for signs and symptoms of heatstroke (sometimes called "sunstroke") (081-831-1008). WARNING Heatstroke must be considered a medical emergency which may result in death if treatment is delayed. Signs/Symptoms. A casualty suffering from heatstroke has usually worked in a very hot, humid environment for a prolonged time. It is caused by failure of the body's cooling mechanisms. Inadequate sweating is a factor. The casualty's skin is red (flushed), hot and dry. He may experience weakness, dizziness, confusion, headaches seizures, nausea (stomach pains), and his respiration and pulse may be rapid and weak. Unconsciousness and collapse may occur suddenly. Treatment. Cool casualty immediately by-- o Moving him to a cool or shaded area (or improvise shade). o Loosening or removing his clothing (except in a chemical environment). *o Spraying or pouring water on him; fanning him to permit a coolant effect of evaporation. o Massaging his extremities and skin which increases the blood flow to those body areas, thus aiding the cooling process. o Elevating his legs. o Having him slowly drink at least one canteen full of water if he is conscious. NOTE Start cooling casualty immediately. Continue cooling while awaiting transportation and during the evacuation. Medical aid. Seek medical aid because the casualty should be transported to a medical treatment facility as soon as possible. Do not interrupt cooling process or lifesaving measures to seek help. Casualty should be continually monitored for development of conditions which may require the performance of necessary basic lifesaving measures, such as clearing the airway, mouth-to-mouth resuscitation, preventing shock, and/or bleeding control.

f. Table. See Table 5-1 for further information.

Table 5-1 Sun or Heat Injuries (081-831-1008)

INJURIES	SIGNS/SYMPTONS	FIRST AID*
Heat cramps	The casualty experiences muscle cramps of arms, legs, and/or stomach. The casualty may also have heavy sweating (wet skin) and extreme thirst.	1. Move the casualty to a shady area or improvise shade and loosen his clothing.+ 2. Give him large amounts of cool water slowly. 3. Monitor the casualty and give him more water as tolerated. 4. Seek medical aid if the cramps continue.
Heat exhaustion	The casualty often experiences profuse (heavy) sweating with pale, moist, cool skin; headache, weakness, dizziness, and/or loss of appetite. The casualty sometimes experiences heat cramps, nausea (with or without vomiting), urge to defecate, chills (gooseflesh), rapid breathing, confusion, and tingling of the hands and/or feet	1. Move the casualty to a cool, shady area or improvise shade and loosen/remove his clothing.+ 2. Pour water on him and fan him to permit coolant effect of evaporation. 3. Have him slowly drink at least one canteen full of water. 4. Elevate the casualty's legs. 5. Seek medical aid if symptoms continue; monitor the casualty until the symptoms are gone or medical aid arrives.
Heatstroke# (sunstroke)	The casualty stops sweating (red [flushed] hot, dry skin). He first may experience headache, dizziness, nausea, fast pulse and respiration, seizures, and mental confusion. He may collapse and suddenly become unconscious. THIS IS A MEDICAL EMERGENCY.	1. Move the casualty to a cool, shady area or improvise shade and loosen or remove the outer garments and protective clothing if the situation permits.+ *2. Start cooling the casualty immediately. Spray or pour water on him. Fan him. Massage his extremities and skin. 3. Elevate his legs. 4. If conscious, have him slowly drink at least one canteen full of water. 5. SEEK MEDICAL AID. CONTINUE COOLING WHILE AWAITING TRANSPORT AND DURING EVACUATION. EVACUATE AS SOON AS POSSIBLE. PERFORM ANY NECESSARY LIFESAVING MEASURES.
* The first aid procedure for heat related injuries caused by wearing individual protective equipment is to move the casualty to a clean area and give him water to drink. + When in a chemical environment, DO NOT loosen/remove the casualty's clothing. # Can be fatal if not treated promptly and correctly.