CH 32

Modification of Heat Gain/Loss

-Increase or decrease heat production -Move to an area where heat loss is decreased or increased -Wear the appropriate clothing for the environment

Recovery Techniques and Resuscitation Efforts Additional aspects of drowning emergencies include: Recovery techniques Resuscitation efforts

-On occasion, you may be called to the scene of a drowning and find that the patient is not floating or visible in the water. An organized rescue effort in these circumstances calls for providers who are experienced with recovery techniques and equipment, including snorkel, mask, and scuba gear. -When a person is submerged in water that is colder than body temperature, heat will be conducted from the body to the water. The resulting hypothermia can protect vital organs from the lack of oxygen. In addition, exposure to cold water will occasionally activate certain primitive reflexes, which may preserve basic body functions for prolonged periods. Whenever a person dives or jumps into very cold water, the diving reflex may cause immediate bradycardia. Loss of consciousness and drowning may follow. The person may be able to survive for an extended period of time under water, thanks to a lowering of the metabolic rate associated with hypothermia. Local protocols often dictate that resuscitative efforts continue for up to 1 hour after submersion, while simultaneously rewarming the patient. Resuscitative efforts are not initiated for unwitnessed drowning victims who are found in a state of decomposition.

Female black widow spider The female black widow spider (Latrodectus) measures approximately 2 inches (5 cm) long with its legs extended. It is usually black and has a distinctive, bright red-orange marking in the shape of an hourglass on its abdomen. The female black widow spider is larger and more toxic than the male. Black widow spiders are found in every state except Alaska. They prefer dry, dim places around buildings, in woodpiles, and among debris. The bite of the black widow spider is sometimes overlooked. If the site becomes numb right away, the patient may not even recall being bit. Most black widow spider bites cause localized pain and symptoms, including agonizing muscle spasms. In some cases, a bite on the abdomen causes muscle spasms so severe that the patient may be thought to have an acute abdominal condition, possibly peritonitis. The main danger is that the black widow's venom can damage nerve tissues, as it is a neurotoxin. Other systemic symptoms include dizziness, sweating, nausea, vomiting, and rashes. Tightness in the chest and difficulty breathing develop within 24 hours, as well as severe cramps, with boardlike rigidity of the abdominal muscles. Generally, these signs and symptoms subside over 48 hours. If necessary, a physician can administer a specific antivenin, but because of a high incidence of side effects, its use is reserved for very severe bites, for older or very feeble patients, and for children younger than 5 years. In children, these bites can be fatal. Emergency treatment of a black widow spider bite consists of BLS for the patient in respiratory distress. More often, the patient will only require pain relief. Transport the patient to the ED as soon as possible for treatment. If possible, safely bring the spider to the hospital or take a photo of the spider with a cell phone and send it to the hospital ahead of time so that it can be definitively identified.

Brown recluse spider The brown recluse spider (Loxosceles) is dull brown and 1-inch (3-cm) long. The shorthaired body has a violin-shaped mark, brown to yellow in color, on its back. Although the brown recluse spider lives mostly in the southern and central parts of the country, it may be found throughout the continental United States. The spider tends to live in dark areas—in corners of old, unused buildings; under rocks; and in woodpiles. In cooler areas, it moves indoors to closets, drawers, cellars, and clothing. The venom of the brown recluse spider is cytotoxic; that is, it causes severe local tissue damage. Typically, the bite is not painful at first but becomes so within hours. The area becomes swollen and tender, developing a pale, mottled, cyanotic center and possibly a small blister. Over the next several days, a scab of dead skin, fat, and debris forms and digs down into the skin, producing a large ulcer that may not heal unless treated promptly. Transport patients with such symptoms as soon as possible. Brown recluse spider bites rarely cause systemic symptoms and signs. When they do, provide BLS and prompt transport to the ED. It is helpful if you can identify the spider and either safely bring it to the hospital with the patient, or take a picture of the spider and send it to the hospital ahead of time.

Cold Exposure

Conduction:is the transfer of heat from a part of the body to a colder object or substance by direct contact, such as when a warm hand touches cold metal or ice, or is immersed in water with a temperature of less than 98°F (36.7°C). Heat can also be gained if the object or substance being touched is warm Convection: occurs when heat is transferred to circulating air, such as when cool air moves across the body surface. A person can gain heat if the air moving across the person's body is hotter than the temperature of the environment, such as in deserts or industrial settings like foundries, but it is more common to see rapid heat gain in spas and hot tubs where the water temperature may be well above body temperature. Evaporation Radiation: is the transfer of heat by radiant energy. Radiant energy is a type of invisible light that transfers heat. Radiation causes heat loss, such as when a person stands in a cold room. Heat can also be gained by radiation—for example, when a person stands by a fire Respiration

Air embolism The most dangerous, and most common, emergency in scuba diving is an air embolism, a condition involving bubbles of air in the blood vessels. An air embolism may occur on a dive as shallow as 6 feet (2 m). The problem starts when the diver holds his or her breath during a rapid ascent. The air pressure in the lungs remains at a high level while the external pressure on the chest decreases. As a result, the air inside the lungs expands rapidly, causing the alveoli in the lungs to rupture. The air released from this rupture can cause: Pneumothorax (where air enters the pleural space and compresses the lungs) Pneumomediastinum (where air enters the mediastinum—the space within the thorax that contains the heart and great vessels) Air emboli Pneumothorax and pneumomediastinum both result in pain and severe dyspnea. An air embolus acts as a plug and prevents the normal flow of blood and oxygen to a specific part of the body. The brain and spinal cord are the organs most severely affected by air embolism. Potential signs and symptoms of an air embolism include: Blotching (mottling of the skin) Froth (often pink or bloody) at the nose and mouth Severe pain in muscles, joints, or abdomen Dyspnea and/or chest pain Dizziness, nausea, and vomiting Dysphasia (difficulty speaking) Cough Cyanosis Difficulty with vision Paralysis and/or coma Irregular pulse and cardiac arrest

Decompression sickness Decompression sickness, commonly called the bends, occurs when bubbles of gas, especially nitrogen, obstruct the blood vessels. This condition results from: Too rapid an ascent from a dive Too long of a dive at too deep a depth Repeated dives within a short period of time During the dive, nitrogen that is being breathed dissolves in the blood and tissues because it is under pressure. When the diver ascends, the external pressure decreases, and the dissolved nitrogen forms small bubbles within the tissues. These bubbles can lead to problems similar to those that occur in air embolism (blockage of tiny blood vessels, depriving parts of the body of their normal blood supply), but severe pain in certain tissues or spaces in the body is the most common problem. The most striking symptom is abdominal and/or joint pain so severe that the patient literally doubles up or "bends." You may find it difficult to distinguish between air embolism and decompression sickness. As a general rule, air embolism occurs immediately on return to the surface, whereas the symptoms of decompression sickness may not occur for several hours. The emergency treatment is the same for both: basic life support (BLS) followed by recompression in a hyperbaric chamber. Recompression treatment allows the bubbles of gas to dissolve into the blood and equalizes the pressures inside and outside the lungs. Once these pressures are equalized, gradual decompression can be accomplished under controlled conditions to prevent the bubbles from re-forming.

Descent Emergencies Descent problems are usually caused by the sudden increase in pressure on the body as the person dives deeper into the water. Some body cavities cannot adjust to the increased external pressure of the water, resulting in severe pain to the lungs, the sinus cavities, the middle ear, the teeth, and the area of the face surrounded by the diving mask. Usually, the pain caused by these "squeeze problems" forces the diver to return to the surface to equalize the pressures, and the problem clears up by itself. A diver who continues to report pain, particularly in the ear, after returning to the surface should be transported to the hospital. A special problem may develop in a person with a perforated tympanic membrane (ruptured eardrum) while diving. If cold water enters the middle ear through a ruptured eardrum, the diver may sustain a loss of balance and orientation. The diver may then shoot to the surface and experience ascent problems.

Emergencies at the Bottom Problems related to the bottom of the dive are rarely seen. They include inadequate mixing of oxygen and carbon dioxide in the air the diver breathes and accidental feeding of poisonous carbon monoxide into the breathing apparatus. Both are the result of faulty connections in the diving gear. These situations can cause drowning or rapid ascent; they require emergency resuscitation and transport of the patient.

Heat cramps

Heat cramps are painful muscle spasms that occur after vigorous exercise. They do not occur only when it is hot outdoors. The exact cause of heat cramps is not well understood. Sweat produced during strenuous exercise, particularly in a warm environment, causes a change in the body's electrolyte balance. Dehydration may also play a role. Large amounts of water loss can result from excessive sweating. This loss of water may affect muscles that are being stressed and cause them to spasm. Heat cramps usually occur in the leg or abdominal muscles. When the abdominal muscles are involved, the pain and muscle spasm may be so severe that the patient appears to have an acute abdominal condition. If a patient with a sudden onset of abdominal cramps has been exercising vigorously in a hot environment, suspect heat cramp

Heat exhaustion

Heat exhaustion is also called heat prostration or heat collapse. The most common heat emergency Heat exposure, stress, and fatigue are causes of heat exhaustion, which is caused by hypovolemia as the result of the loss of water and electrolytes from heavy sweating. People who work or exercise vigorously and those who wear heavy clothing in a warm, humid, or poorly ventilated environment are particularly prone to heat exhaustion. The signs and symptoms of heat exhaustion and those of associated hypovolemia include: Dizziness, weakness, or syncope signifying a change in level of consciousness with accompanying nausea, vomiting, or headache Muscle cramping, including abdominal cramping Onset while working vigorously or exercising in a hot, humid, or poorly ventilated environment and sweating heavily Onset, even at rest, in the older and infant age groups in hot, humid, and poorly ventilated environments or after extended time in hot, humid environments Cold, clammy skin with ashen pallor Dry tongue and thirst Normal vital signs, although the pulse is often rapid and weak (an indication for use of pulse oximetry) and the diastolic blood pressure may be low Normal or slightly elevated body temperature; on rare occasions, as high as 104°F (40°C) People who are not acclimatized to the environment may also experience onset at rest.

Heat Stroke

Heat stroke is the least common but most serious heat emergency. Occurs when the body is subjected to more heat than it can handle and normal mechanisms for getting rid of the excess heat are overwhelmed Body temperature rises rapidly to the level at which tissues are destroyed. Untreated heat stroke always results in death. Heat stroke can develop: In patients during vigorous physical activity or when they are outdoors or in a closed, poorly ventilated, humid space During heat waves among people (particularly geriatric patients) who live in buildings with no air conditioning or with poor ventilation In children who are left unattended in a locked vehicle on a hot day Many patients with heat stroke have hot, dry, flushed skin because their sweating mechanism has been overwhelmed. A patient can have heat stroke even if he or she is still sweating. This presentation is often seen in endurance athletes, military personnel, or emergency providers who wear personal protective equipment. Body temperature may rise to 106°F (41.1°C) or more. As core temperature rises, the patient's LOC decreases, resulting in unconsciousness. Often, the first sign of heat stroke is a change in behavior. The patient becomes unresponsive very quickly and seizures may occur. Pulse is usually rapid and strong at first, but as the patient becomes increasingly unresponsive, the pulse becomes weaker and the blood pressure falls. Respiratory rate increases as the body attempts to compensate.

Heat Exposure

Hyperthermia is a high core temperature, usually 101°F (38.3°C) or higher. High air temperature can reduce heat loss by radiation. High humidity reduces heat loss through evaporation. Risk factors include: The inability to acclimate to the heat Vigorous exercise, during which sweat loss can exceed 1 liter an hour, causing loss of fluid and electrolytes A heat emergency can take three forms: Heat cramps Heat exhaustion Heat stroke All three forms may be present in the same patient because untreated heat exhaustion may progress to heat stroke. Heat stroke is life threatening. People at greatest risk for a heat emergency are: Children Geriatric patients Patients with heart disease, COPD, diabetes, dehydration, and obesity Those with limited mobility Older people, newborns, and infants exhibit poor thermoregulation. Alcohol and certain drugs, including medications that dehydrate the body or decrease the ability of the body to sweat, also make a person more susceptible to heat emergencies. When treating someone for a heat emergency, always obtain a medication history.

Hypothermia

Hypothermia means "low temperature" and occurs when core temperature falls below 95°F (35°C). To protect itself against heat loss, the body: Constricts blood vessels in the skin, which results in the characteristic appearance of blue lips and/or fingertips Creates additional heat by shivering As cold exposure worsens and these mechanisms are overwhelmed, many body functions slow down and mental status deteriorates. Eventually, the functioning of key organs, such as the heart, begins to slow. Untreated, this can lead to death. Hypothermia is more common among: Geriatric, pediatric, and ill people, who are less able to adjust to temperature extremes Patients with injuries or illness, such as burns, shock, head injury, stroke, generalized infection, injuries to the spinal cord, diabetes, and hypoglycemia Patients who have taken certain drugs or consumed alcohol

High Altitude Dysbarism injuries are any signs and symptoms caused by the difference between the surrounding atmospheric pressure and the total gas pressure in various tissues, fluids, and cavities of the body. Altitude illnesses occur when an unacclimatized person is exposed to diminished oxygen pressure in the air at high altitudes. These illnesses affect the central nervous system (CNS) and pulmonary systems, and range from: Acute mountain sickness Caused by diminished oxygen pressure in the air at altitudes above 5,000 feet (1.5 km), resulting in diminished oxygen in the blood (hypoxia) Signs and symptoms include a headache, light-headedness, fatigue, loss of appetite, nausea, difficulty sleeping, shortness of breath during physical exertion, and a swollen face. Treatment primarily consists of stopping the ascent and descending to a lower altitude. Consider other possible causes for the same symptoms, such as hypoglycemia or carbon monoxide poisoning from a camping stove. High-altitude pulmonary edema (HAPE) Fluid collects in the lungs, hindering the passage of oxygen into the bloodstream. It can occur at altitudes of 8,000 feet (2 km) or greater. Signs and symptoms include shortness of breath, cough with pink sputum, cyanosis, and a rapid pulse. High-altitude cerebral edema (HACE) Usually occurs in climbers and may accompany HAPE It can quickly become life threatening. Signs and symptoms include a severe, constant, throbbing headache; ataxia (lack of muscle coordination and balance); extreme fatigue; vomiting; and loss of consciousness. The symptoms of HACE and HAPE may overlap. In the field, treatment for HAPE and/or HACE consists of providing oxygen, descending to a lower altitude, and prompt transport. For inadequate respirations, provide positive-pressure ventilation with a BVM. If local protocols allow, continuous positive airway pressure (CPAP) may be very helpful for a patient with respiratory distress from HAPE.

Lightning The energy associated with lightning is comprised of direct current of up to 200,000 amps and a potential of 100 million volts or more. Temperatures generated from lightning vary between 20,000°F and 60,000°F (11,000°C and 33,000°C). Any type of activity that exposes the person to a large, open area increases the risk of being struck by lightning. The current associated with the lightning discharge travels along the ground. Although some people are injured or killed by a direct lightning strike, many people are indirectly struck when standing near an object that has been struck by lightning, such as a tree (splash effect). The tissue damage caused by lightning is different from that caused by other electricity-related injuries (ie, high-power-line injuries) because the tissue damage pathway usually occurs over the skin, rather than through it. Look for entrance and exit wounds. The exit wound does not necessarily occur on the same side of the body. Because the duration of a lightning strike is short, skin burns are usually superficial; full-thickness (third-degree) burns are rare. Lightning injuries are categorized as being: Mild: Loss of consciousness, amnesia, confusion, tingling, and other nonspecific signs and symptoms. Burns, if present, are typically superficial. Moderate: Seizures, respiratory arrest, dysrhythmias that spontaneously resolve, and superficial burns Severe: Cardiopulmonary arrest. Because of the delay in resuscitation, often the result of occurrence in a remote location, many of these patients do not survive.

Management of Heat Cramps Take the following steps to treat heat cramps in the field: Promptly remove the patient from the hot environment, including direct sunlight. Loosen any tight clothing. Administer high-flow oxygen if indicated (the patient shows signs of hypoxia or respiratory distress), if this was not already done as part of the primary assessment. Rest the cramping muscles. Have the patient sit or lie down until the cramps subside. Replace fluids by mouth. Give water or a diluted (half-strength) balanced electrolyte solution, such as a sports drink. In most cases, plain water is the most useful. Do not give salt tablets or solutions that have a high salt concentration. Cool the patient with cool water spray or mist, and add convection to the cooling method by manually or mechanically fanning the patient. The best preventive and treatment strategy is hydration by drinking sufficient quantities of water.

Managing Heat Stroke Move the patient out of the hot environment and into the ambulance. Set the air conditioning to maximum cooling. Remove the patient's clothing. Administer high-flow oxygen if indicated, if this was not already done as part of the primary assessment. If needed, assist the patient's ventilations with a BVM and appropriate airway adjuncts as per your protocol. If the patient is unresponsive and unable to protect his or her airway, consider rapid transport and cooling en route. Consult medical control if available. Provide cold-water immersion in an ice bath, if possible. Cooling should begin immediately and continue en route to the hospital. If it is not possible to cool en route and cold-water immersion is available at the scene, continue cold-water immersion at the scene until the core body temperature is between 101°F and 102°F (38.3°C and 38.9°C). Cover the patient with wet towels or sheets, or spray the patient with cool water and fan him or her to quickly evaporate the moisture on the skin. Aggressively and repeatedly fan the patient with or without dampening the skin. Exclude other causes of altered mental status and check blood glucose level, if possible. Provide rapid transport to the hospital. Notify the hospital as soon as possible. Do not overcool the patient. Call for ALS assistance if the patient begins to shiver.

Signs and Symptoms of Hypothermia To assess the patient's core body temperature (CBT), pull back on your glove and place the back of your hand on the patient's skin at the abdomen. If you work in a cold environment, and/or depending on local protocols, you may carry a hypothermia thermometer, which registers lower core temperatures. It must be inserted in the rectum for an accurate reading. Regular thermometers will not register the temperature of a patient who has significant hypothermia. If the skin feels cool, the patient is likely experiencing a generalized cold emergency.

Mild Mild hypothermia occurs when the core temperature is between 90°F and 95°F (32.2°C and 35°C). The patient is usually alert and shivering in an attempt to generate heat through muscular activity. Pulse rate and respirations are usually rapid. The skin in light-skinned people can be red, but may eventually appear pale, then cyanotic. People in a cold environment may have blue lips or fingertips because of the body's constriction of blood vessels at the skin to retain heat. Severe More severe hypothermia occurs when the core temperature is less than 90°F (32.2°C). Shivering stops and muscular activity decreases. At first, small, fine muscle activity such as coordinated finger motion ceases. Eventually, as the temperature falls further, all muscle activity stops and mental status deteriorates. As the core temperature drops toward 85°F (29.4°C): The patient becomes lethargic and usually stops fighting the cold. Level of consciousness (LOC) decreases, and the patient may try to remove his or her own clothes. Poor coordination and memory loss follow, along with reduced or complete loss of sensation to touch, mood changes, and impaired judgment. The patient becomes less communicative, experiences joint or muscle stiffness, and has trouble speaking. The patient begins to appear stiff or rigid. If the core temperature continues to fall to 80°F (26.7°C): Vital signs slow. The pulse becomes slower and weaker. Respirations become shallow or absent. Cardiac dysrhythmias may occur as blood pressure decreases. At a core temperature of less than 80°F (26.7°C): All cardiorespiratory activity may cease. Pupillary reaction is slow. The patient may appear dead. Never assume that a cold, pulseless patient is dead. Patients may survive severe hypothermia if proper emergency care is provided. Perform an extended pulse check (up to a full minute). Assess at the carotid or femoral pulse. A patient in apparent cardiac arrest from hypothermia should not be considered dead until aggressive rewarming has been attempted, along with resuscitation. Remember the saying: "No one is dead unless they are warm and dead." It is important to note that patients who have died from a cause other than hypothermia will be cold to the touch; however, there will be additional, obvious signs of death such as rigor mortis. The "warm and dead" rule does not apply to such patients

Hymenoptera Stings Hymenoptera (bees, wasps, yellow jackets, and ants) stings are painful but are not a medical emergency. Remove the stinger and, if still present, the venom sac. This is best done by using a firm-edged item such as a credit card to scrape the stinger and sac off the skin. Use ice packs to assist in controlling pain from a hymenoptera sting. The signs and symptoms of anaphylaxis are: Flushed skin Low blood pressure Difficulty breathing, usually associated with reactive airway sounds such as wheezes, or, in severe cases, diminished or absent breath sounds Hives (urticaria) may develop near the site of envenomation or centrally on the body. The patient can also have swelling to the throat and tongue. Anaphylaxis is a true emergency and can be fatal if not recognized and treated quickly. If anaphylaxis develops, be prepared to assist the patient in administering an epinephrine auto-injector (EpiPen), and support the airway and breathing should the patient experience significant respiratory compromise.

Snake Bites Venomous snakes in the United States include: The rattlesnake (Crotalus) The copperhead (Agkistrodon contortrix) The cottonmouth, or water moccasin (Agkistrodon piscivorus) The coral snakes (Micrurus fulvius and Micruroides euryxanthus) At least one of these venomous species is found in every state except Alaska, Hawaii, and Maine. Use extreme caution on these calls and be sure to wear the proper protective equipment for the area. In general, only one-third of snake bites result in significant local or systemic injuries. Often, envenomation does not occur because the snake has recently struck another animal and exhausted its supply of venom for the time being. Venomous snakes native to the United States all have hollow fangs in the roof of the mouth that inject the venom from two sacs at the back of the head. The classic appearance of the venomous snake bite is two small puncture wounds, usually about 0.5 inch (1 cm) apart, with discoloration and swelling, and the patient usually reports pain surrounding the bite. A snake bite with other tooth marks may be from a nonvenomous snake. If you are unsure whether the snake was venomous, proceed as if it was, especially if the patient exhibits other signs and symptoms. A person who has been bitten by any venomous snake needs prompt transport. Notify the hospital as soon as possible if a patient has been bitten by a pit viper or coral snake. Some venoms can cause paralysis of the nervous system, and hospitals may not have appropriate antivenin on hand.

Local Cold Injuries

The following body parts are especially vulnerable to cold injury: Extremities (feet and hands) Ears Nose Face Cold injuries include: Frostnip and immersion foot Frostnip occurs after prolonged exposure to the cold, when the skin may freeze but the deeper tissues are unaffected. Because frostnip is usually painless, the patient often is unaware that a cold injury has occurred. Immersion foot (also called trench foot) occurs after prolonged exposure to cold water. It is particularly common in hikers or hunters who stand for a long time in a river or lake. With both frostnip and immersion foot, the skin is pale (blanched) and cold to the touch; normal color does not return after palpation of the skin. In some cases, the skin of the foot will be wrinkled, but it can also remain soft. The patient reports loss of feeling and sensation in the injured area. Frostbite is the most serious local cold injury because the tissues are actually frozen. Freezing permanently damages cells. The presence of ice crystals within the cells may cause physical damage. The change in the water content in the cells may also cause changes in the concentration of critical electrolytes, producing permanent changes in the chemistry of the cell. When the ice thaws, further chemical changes occur in the cell, causing permanent damage or cell death, called necrosis or gangrene. If gangrene occurs, the dead tissue must be surgically removed, sometimes by amputation. Following less-severe damage, the exposed part will become inflamed, tender to touch, and unable to tolerate exposure to cold. Frostbite can be identified by the hard, waxy feel of the affected tissues. The injured part feels firm to frozen as you gently touch it. If the frostbite is only skin deep, it will feel leathery or thick instead of hard. Blisters and swelling may be present. In light-skinned people with a deep injury that has thawed or partially thawed, the skin may appear red or white, or it may be mottled and cyanotic (purple and blue). The depth of skin damage will vary. With superficial frostbite, only the skin is frozen. With deep frostbite, the deeper tissues are frozen as well. You may not be able to tell superficial from deep frostbite in the field. If possible, determine: The duration of the exposure The temperature to which the body part was exposed The wind velocity during exposure These will help you determine the severity of a local cold injury. You should also investigate: Exposure to wet conditions Inadequate insulation from cold or wind Restricted circulation from tight clothing or shoes or circulatory disease Fatigue Poor nutrition Alcohol or drug abuse Hypothermia Diabetes Cardiovascular disease Age

General Management of Cold Emergencies

To prevent further damage to the feet, do not allow the patient to walk. Remove any wet clothing and place dry blankets over and under the patient. If available, give the patient warm, humidified oxygen if you have not already done so. Rough handling of a patient with moderate to severe hypothermia may cause the heart to go into ventricular fibrillation, which may not respond to defibrillation. Do not massage the extremities. Do not allow the patient to eat or to use any stimulants, such as coffee, tea, soda, or tobacco products. Stimulants are vasoconstrictors, which may further impair circulation to affected areas. If the patient is alert, is shivering, responds appropriately, and has a core body temperature is between 90°F to 95°F (32.2°C to 35°C), the hypothermia is mild. Begin passive rewarming slowly, which includes placing the patient in a warm environment; removing wet clothing; and applying heat packs or hot water bottles to the groin, axillary, and cervical regions. Turn the heat up high in the patient compartment of the ambulance. Do not place heat packs directly on the skin. You may give warm fluids by mouth, as allowed by local protocols, assuming that the patient is alert and can swallow without difficulty. When the patient has moderate or severe hypothermia, active rewarming is best accomplished in the emergency department (ED). Therapies might include warm intravenous fluids, lavage with warm fluids, and rewarming blood outside the body before reintroducing it (extracorpeal rewarming). Rewarming the patient too quickly may cause a fatal cardiac dysrhythmia or other significant complications. For this reason, local protocols may dictate the appropriate type of rewarming strategies based on the patient's core body temperature. Your goal is to prevent further heat loss. Remove the patient immediately from the cold environment, place the patient in the ambulance, remove wet clothing, cover the patient with blankets, and transport The emergency treatment of local cold injuries in the field should include the following steps: Remove the patient from further exposure to the cold. Handle the injured part gently, and protect it from further injury. Remove any wet or restricting clothing from the patient, especially over the injured part. With frostnip, contact with a warm object may be all that the patient needs. Use your hands or the patient's own body (for example, have the patient tuck his or her hands into the armpits). During rewarming, the affected part will often tingle and become red in light-skinned people. With immersion foot, remove wet shoes, boots, and socks, and rewarm the foot gradually, protecting it from further cold exposure. Splint the extremity and cover it loosely with a dry, sterile dressing. Never rub or massage injured tissues, which could cause further damage. Do not reexpose the injury to cold. With a late or deep cold injury, such as frostbite, remove any jewelry from the injured part and cover the injury loosely with a dry, sterile dressing. Do not break blisters or rub or massage the area. Do not apply heat or rewarm the part. Rewarming of the frostbitten extremity is best accomplished in the ED. Do not allow the patient to stand or walk on a frostbitten foot. Evaluate the patient's general condition for the signs or symptoms of systemic hypothermia. Support the vital functions as necessary, and provide rapid transport to the hospital. If prompt hospital care is unavailable and medical control instructs you to begin rewarming in the field, use a warm-water bath. Immerse the frostbitten part in water with a temperature between 102°F and 104°F (38.9°C and 40°C). Check the water temperature with a thermometer before immersing the limb, and recheck it frequently during the rewarming process. The water temperature should never exceed 105°F (40.6°C). Keep the frostbitten part in the water until it feels warm and sensation has returned to the skin. Dress the area with dry, sterile dressings, placing them also between injured fingers or toes. Expect the patient to report severe pain. Cover the frostbitten part with soft, padded, sterile cotton dressings. If blisters have formed, do not break them.

Scorpion Stings The Centrurodes sculpturatus is the only venomous scorpion in the United States. It is found naturally in Arizona and New Mexico, as well as parts of Texas, California, and Nevada, but it may be kept as a pet by anyone. The venom may produce a severe systemic reaction that leads to: Circulatory collapse Severe muscle contractions Excessive salivation Hypertension Convulsions Cardiac failure Antivenin is available but must be administered by a physician. Administer BLS and provide rapid transport to the ED.

Tick Bites Ticks commonly carry two infectious diseases: Rocky Mountain spotted fever Not limited to the Rocky Mountains area Occurs within 7 to 10 days after a bite by an infected tick Symptoms include: Nausea and vomiting Headache Weakness Paralysis Possible cardiorespiratory collapse Lyme disease Originally seen only in Connecticut, it has now been reported in all states with the exception of Hawaii. Occurs most commonly in the Northeast and the Great Lake states The first symptoms are generally fever and flulike symptoms, sometimes associated with a bull's-eye rash that may spread to several parts of the body. After a few days or weeks, painful swelling of the joints, particularly the knees, occurs. Both diseases are spread through the tick's saliva, which is injected into the skin when the tick attaches itself. The longer a tick stays embedded, the greater the chance that a disease will be transmitted. Bites occur most commonly during the summer months. Do not attempt to suffocate the tick with gasoline or petroleum jelly, or burn it with a lighted match; you will only increase the risk of infection or burn the patient. To remove a tick: Using fine tweezers, grasp the tick by the head and pull gently but firmly straight up so that the skin is tented. Hold this position until the tick releases. Cleanse the area with antiseptic and save the tick in a glass jar or other container so that it can be identified. Do not handle the tick with your fingers. The patient should follow up with their health care provider as soon as possible.

Pit Vipers The fangs of the pit viper normally lie flat against the roof of the mouth and are hinged to swing back and forth as the mouth opens. When the snake strikes, the mouth opens wide and the fangs extend to penetrate whatever the mouth strikes. The fangs are actually special hollow teeth connected to a sac containing a reservoir of venom, which in turn is attached to a poison gland. The gland itself is a specially adapted salivary gland, which produces enzymes that digest and destroy tissue. The primary purpose of the venom is to kill small animals and facilitate the digestive process. The signs of envenomation by a pit viper are severe burning pain at the site of the injury, followed by swelling and a blue discoloration (ecchymosis) in light-skinned people that signals bleeding under the skin. Other systemic signs, which may or may not occur, include weakness, nausea, vomiting, sweating, seizures, fainting, vision problems, changes in LOC, and shock. If swelling has occurred, use a pen to mark its edges on the skin. This will allow physicians to assess the timing and extent of the swelling with greater accuracy. If the patient has no local signs an hour after being bitten, it is safe to assume that envenomation did not take place. The toxicity is related to the amount of toxin injected. A bite will affect children more than adults because there is less body mass to absorb the toxin. The same principle holds true for a small-statured adult.

Treating a Pit Viper Bite In treating a snake bite from a pit viper, follow these steps: Calm the patient; assure him or her that venomous snake bites are rarely fatal. Place the patient in a supine position and explain that staying still will slow the spread of any venom through the system. Determine the approximate time of the bite and document your time en route to a receiving facility. This time from onset to evaluation at the facility is one of the criteria used in grading the severity of the incident and in determining the amount of antivenin to be used. Locate the bite area; clean it gently with soap and water or a mild antiseptic. Do not apply ice to the area. If the bite occurred on an arm or leg, consider the use of a pressure immobilization bandage of the extremity (eg, 40 to 70 mm Hg in the arms and 55 to 70 mm Hg in the legs) and place the affected extremity below the level of the heart. Be alert for an anaphylactic reaction to the venom and treat with an epinephrine auto-injector, as appropriate. Do not give anything by mouth, and be alert for vomiting. If, as rarely happens, the patient was bitten on the trunk, keep him or her supine and quiet and transport as quickly as possible. Monitor the patient's vital signs and mark the skin with a pen over the area that is swollen, proximal to the swelling, to note whether swelling is spreading. If there are any signs of shock, place the patient supine and administer oxygen. If the snake has been killed, be sure to bring it with you in a secure, hard-sided container so that physicians can identify it and administer the proper antivenin. Alternatively, take a picture of the snake with a cell phone and send it to the hospital ahead of time. Notify the hospital that you are bringing in a patient who has a snake bite; if possible, describe the snake. Transport the patient promptly to the hospital. If the patient shows no sign of envenomation, provide BLS as needed, place a sterile dressing over the suspected bite area, and immobilize the injury site.

Drowning Drowning is the process of experiencing respiratory impairment from submersion or immersion in liquid. Major risk factors for drowning include: Alcohol consumption Preexisting seizure disorders Geriatric patients with cardiovascular disease Unsupervised access to water Young children can drown in as little as 1 inch (3 cm) of water if left unattended. Inhaling very small amounts of either fresh or salt water can severely irritate the larynx, sending the muscles of the larynx and the vocal cords into spasm (laryngospasm). Laryngospasm prevents more water from entering the lungs. In severe cases such as water submersion, the patient's lungs cannot be ventilated because significant laryngospasm is present. Progressive hypoxia occurs until the patient becomes unconscious. At this point, the spasm relaxes, making rescue breathing possible. If the patient has not already been removed from the water, the patient may now inhale deeply, and more water may enter the lungs.

Water Rescue First, try to reach for the patient. If that does not work, throw the patient a rope, a life preserver, or any floatable object that is available. Next, use a boat if one is available. Do not attempt a swimming rescue unless you are trained and experienced in the proper techniques. Even then, you should always wear a helmet and a personal flotation device. In cold climates or cold-water locations, rapid hypothermia is also a concern for rescuers. The steps for ice rescue are similar and may involve reaching with a pole or ladder or throwing a rope or floatation device. A victim who has fallen through the ice may also be coached into placing his or her arms out of the water and onto the ice, kicking and rolling out of the water, and crawling to safety. Because the success of any water rescue depends on how rapidly the patient is removed from the water and ventilated, make sure you always have immediate access to personal flotation devices and other rescue equipment. Survival rates drastically decline the longer a victim is immersed. Cold-water drowning survival rates are somewhat higher.