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Chapter 15 Environmental Emergencies Chapter 15: Environmental Emergencies Objectives (1 of 4) • List the signs and symptoms of exposure to cold. • Explain the steps in providing emergency medical care to a patient exposed to cold. • List the signs and symptoms of high altitude illnesses. • Explain the steps in providing emergency care to a patient with high altitude illness. 2 Chapter 15: Environmental Emergencies Objectives (2 of 4) • Explain the steps in providing emergency care for an avalanche victim. • List the signs and symptoms of exposure to heat. • Explain the steps in providing emergency care to a patient exposed to heat. 3 Chapter 15: Environmental Emergencies Objectives (3 of 4) • Explain the steps in providing emergency care for a patient who has been struck by lightning or received an electrical injury. • Recognize the signs and symptoms of waterrelated emergencies. • Demonstrate the assessment and emergency care of a patient with exposure to cold. • Demonstrate the assessment and emergency care of a patient with high altitude illnesses. 4 Chapter 15: Environmental Emergencies Objectives (4 of 4) • Demonstrate the assessment and emergency care of an avalanche victim. • Demonstrate the assessment and emergency care of a patient with exposure to heat. • Demonstrate the assessment and emergency care of a patient affected by lightning or electrical exposure. 5 Chapter 15: Environmental Emergencies Cold Exposure • Normal body temperature exists within a narrow range • Cold may cause injury to parts of the body • Cold may cause injury to the body as a whole 6 Chapter 15: Environmental Emergencies Loss of Body Heat (1 of 2) • Conduction – Transfer of heat from body to colder object • Convection – Transfer of heat through circulating air • Evaporation – Cooling of body through sweating • Radiation – Loss of body heat directly into a colder environment • Respirations – Loss of body heat during breathing 7 Chapter 15: Environmental Emergencies Loss of Body Heat (2 of 2) • Rate and amount of heat loss can be modified in three ways: – Increase heat production (shivering). – Move to sheltered area where heat loss is decreased. – Wear insulated clothing. 8 Chapter 15: Environmental Emergencies Hypothermia • Lowering of the body temperature below 95°F (35ºC) • Weather does not have to be below freezing for hypothermia to occur. • As the body cools, functions slow. • A cooler body loses the ability to regulate temperature and to generate heat. • The patient is unaware of the change and the condition is insidious. 9 Chapter 15: Environmental Emergencies Hypothermia Risks • Elderly persons and infants are at higher risk. • People with other illnesses and injuries are susceptible to hypothermia. • High altitude can increase the risk. 10 Chapter 15: Environmental Emergencies Hypothermia and Death • 50% of severe cases are lethal. • Patients may appear dead, but: – “No one is dead until warm and dead!” – Death is usually the result of ventricular fibrillation (V-fib). 11 Chapter 15: Environmental Emergencies Hypothermia Categories • Grouped into three categories: – Acute (less than an hour) – Subacute (1 to 24 hours) – Chronic (a day or more) 12 Chapter 15: Environmental Emergencies Mild Hypothermia • Rectal temperature above 90°F (32°C) • Shivering can provide needed heat. • Treat dehydration with warm, sweetened liquids. • Avoid alcohol and caffeine. 13 Chapter 15: Environmental Emergencies Severe Hypothermia • Rectal temperature below 90°F (32°C) • Out-of-hospital mortality is high due to V-fib, metabolic, or electrolyte complication. • Best results occur with detection, stabilization of core temperature, gentle handling, and transport. 14 Chapter 15: Environmental Emergencies Severe Hypothermia Treatment (1 of 2) • Spend several minutes evaluating vital signs. • Avoid aggressive rewarming. • CPR can precipitate V-fib. • If CPR is started, it must continue until hospitalization. 15 Chapter 15: Environmental Emergencies Severe Hypothermia Treatment (2 of 2) • Carefully evaluate the method of evacuation. Avoid rough handling. • In a wilderness setting, use a slow rewarming method, usually body-tobody contact. 16 Chapter 15: Environmental Emergencies Hypothermia Settings • Immersion—contact with cold water • Field—contact with cold weather • Urban—individuals predisposed to poor or inadequate thermoregulation • Submersion—drowning and near drowning 17 Chapter 15: Environmental Emergencies Assessment of Hypothermic Patients (1 of 2) • It is always preferable to anticipate and prevent. • Mental status and physical actions can help estimate core temperature. – Shivering and appropriate actions, temperature > 90°F (32°C) – Uncoordinated actions and no shivering, temperature < 90°F (32°C) 18 Chapter 15: Environmental Emergencies Assessment of Hypothermic Patients (2 of 2) • Scene size-up – Include consideration of setting and predisposing conditions. • Initial assessment: – Prevent further heat loss. – Take your time assessing vital signs. 19 Chapter 15: Environmental Emergencies Emergency Medical Care • Stabilize body temperature and prevent further heat loss. • Rewarm the patient appropriately. • Rewarm the core first if possible. • Treat gently. • If conscious, give warm sweet fluids to treat dehydration. 20 Chapter 15: Environmental Emergencies Rewarming Methods: Fast • Usually water based – Baths – Heated blankets – Peritoneal dialysis – Heart-lung machine 21 Chapter 15: Environmental Emergencies Rewarming Methods: Slow • • • • • • Shivering Body-to-body contact Hot water bottles or warm rocks Chemical heating pads O2 heater Stoves or fires 22 Chapter 15: Environmental Emergencies Local Cold Injuries (1 of 3) 23 Chapter 15: Environmental Emergencies Local Cold Injuries (2 of 3) • Frostnip – Cold-induced superficial blood vessel constriction • Immersion (trench) foot – Prolonged exposure to cold water • Frost bite – Freezing of a body part, usually an extremity 24 Chapter 15: Environmental Emergencies Local Cold Injuries (3 of 3) • Investigate any predisposing factors. • The development of frostbite is progressive. • It is difficult to predict the severity of injury and the patient’s outcome. 25 Chapter 15: Environmental Emergencies Frostbite • The actual freezing of a body part • The amount of damage depends on the extent and duration of freezing. • The part will have a wooden or waxy appearance. • Blisters often form with thawing. • Gangrene is a complication in severe cases. 26 Chapter 15: Environmental Emergencies Assessment and Emergency Care of Frostbite • Based on direct inspection and palpation • For frostnip, provide direct body heat and seek shelter. • Consider the possibility of hypothermia. • Rewarm the part rapidly in a water bath. 27 Chapter 15: Environmental Emergencies Water Bath • Water temperature should be between 102oF to 108oF. • Recheck water temperature and stir to circulate. • Remove constricting bands: rings, watches, etc. • Keep body part in water for 20 to 30 minutes. • Watch for tissue color change. • Give warm drinks and advise of impending pain. 28 Chapter 15: Environmental Emergencies Wilderness and Frostbite • Refreezing will lead to gangrene. • Wrap in bulky dressings and leave blisters intact if possible. • Patients can be evacuated after thawing, but guard against refreezing. • Prevention is the best treatment! 29 Chapter 15: Environmental Emergencies Cold Exposure and You • Rescuers are at risk for hypothermia when working in a cold environment. • Stay aware of local weather conditions. • Dress appropriately and be prepared. • Never allow yourself to become a casualty! 30 Chapter 15: Environmental Emergencies High Altitude Illness (1 of 5) • With ascent, the following changes occur: – Solar radiation increases. – Temperature and humidity fall. – PO2 and atmospheric pressure decrease. 31 Chapter 15: Environmental Emergencies High Altitude Illness (2 of 5) • For every 1000’ (309 m) of altitude gain: – Dry temperatures drop 3.5°F (1.6°C). – The barometer drops 20 mm Hg. – Ultraviolet radiation increases 5%. – Oxygen concentration remains constant at 21%, but the PO2 drops. 32 Chapter 15: Environmental Emergencies High Altitude Illness (3 of 5) • Rapid ascent produces acute and chronic effects. • Acute effects are due to hypoxia. • Chronic effects lead to circulatory, respiratory, and nervous system changes. 33 Chapter 15: Environmental Emergencies High Altitude Illness (4 of 5) • Factors that influence the effects of altitude include: – Speed of ascent – Final altitude attained – Duration of exposure – Exertion – Type of travel: foot, car, airplane – The altitude at which one sleeps 34 Chapter 15: Environmental Emergencies High Altitude Illness (5 of 5) • Types of illnesses: – Acute mountain sickness (AMS) – High altitude cerebral edema (HACE) – High altitude pulmonary edema (HAPE) 35 Chapter 15: Environmental Emergencies Acute Mountain Sickness (1 of 3) • The most common high-altitude illness • Reported in 20% of all snowsports guests at Rocky Mountain resorts • Documented in Yellowstone National Park • Caused by: – Failure to increase respirations – Fluid retention – Increased cerebral blood flow and inflammation 36 Chapter 15: Environmental Emergencies Acute Mountain Sickness (2 of 3) • Signs and symptoms include: – Headache, worse at night or when bending over – Apathy – Insomnia – Lightheadedness – Loss of appetite, nausea, and vomiting – Other generalized symptoms of malaise 37 Chapter 15: Environmental Emergencies Acute Mountain Sickness (3 of 3) • Predisposing factors include: – – – – Speed of ascent Overexertion Cold weather Youthfulness in adults • Fitness does not seem to promote immunity. • A brisk respiratory response seems to lessen susceptibility. 38 Chapter 15: Environmental Emergencies High Altitude Cerebral Edema • Signs and symptoms include: – Similar to AMS, but more intense – Ataxia, the inability to balance or walk – Altered mental status progressing to unresponsiveness 39 Chapter 15: Environmental Emergencies High Altitude Pulmonary Edema (1 of 3) • 10X more frequent than HACE • Researched extensively in the Himalayas, Canada, and Alaska • Hypoxia-induced changes lead to: – – – – Increased pulmonary arterial pressure Capillary wall damage Opening of high pressure shunts Increased fluid in alveoli 40 Chapter 15: Environmental Emergencies High Altitude Pulmonary Edema (2 of 3) • Early signs and symptoms include: – Dry, nighttime cough – Increasing dyspnea – Mild chest pain – A decrease in the ability to exercise 41 Chapter 15: Environmental Emergencies High Altitude Pulmonary Edema (3 of 3) • Late signs and symptoms include: – Cyanosis – Cough that produces pink frothy sputum – Tachycardia and tachypnea at rest – Loud, wet rales – Severe dyspnea 42 Chapter 15: Environmental Emergencies Assessment of High Altitude Illness • Scene size-up, consider setting • Initial assessment, especially respiratory rate and rhythm • Complete SAMPLE history • Assess lung sounds, the ability to walk, and balance. 43 Chapter 15: Environmental Emergencies Emergency Care of High Altitude Illness (1 of 2) • Skiing, trekking, and climbing parties: – – – – Rapid descent for HACE and HAPE patients Preferably 2,000’ (610 m) O2 (1 to 2 L/min), if available Rest, without further ascent, may resolve mild AMS. – Aspirin or ibuprofen for headache (HA) – Gamow bag 44 Chapter 15: Environmental Emergencies Emergency Care of High Altitude Illness (2 of 2) • High altitude resorts – – – – Rapid access to medical treatment High-flow oxygen May require immediate descent Rest, mild diet, and abstinence may resolve mild AMS. – Prescriptions can help acutely and prophylactically 45 Chapter 15: Environmental Emergencies Sunburn, Windburn, and Snowblindness • Altitude, snow, and bodies of water increase risk. • Clouds do not offer protection. • Sunburn is a 1° or 2° burn cause by ultraviolet light: – UVA at 290 – 320 nanometers – UVB at 320 – 400 nanometers 46 Chapter 15: Environmental Emergencies Sunburn • Repeated exposures can lead to: – Wrinkling, darkening, and thickening of skin – Benign and malignant cancers Actinic keratoses, basal and squamous cell carcinomas Malignant melanoma 47 Chapter 15: Environmental Emergencies Types of Sunscreen • Physical – Blocks the sunlight mechanically – Zinc oxide, titanium dioxide, red petrolatum • Chemical – Chemicals filter rays – UVA- Parsol, anthranilates, oxybensone – UVB- salicylates, cinnamates, PABA, Padimate 48 Chapter 15: Environmental Emergencies Sunscreen • Sun protection factor (SPF), 2 to 50 – Number refers to how much longer a person can be safely exposed. – SPF 15 is the practical minimum; SPF 30 is the practical maximum. • Apply early and often. Thicker preparations can prevent windburn as well. • Treat burn patients with cool compresses and later with lotion and aloe. • Extensive/blistered burns need physician care. 49 Chapter 15: Environmental Emergencies Snowblindness • A burn of the conjunctiva caused by UV radiation • Can be prevented by wearing sunglasses or goggles • Symptoms develop 6 to 12 hours after exposure. 50 Chapter 15: Environmental Emergencies Snowblindness: Signs and Symptoms • • • • • “Sand in the eye” irritation Pain with eye motion Tearing Light sensitivity Swelling around the eye 51 Chapter 15: Environmental Emergencies Snowblindness Treatment • • • • • Remove to darker surroundings Cover both eyes Apply cool compresses. Nonprescription pain relievers Prescription medications in severe cases 52 Chapter 15: Environmental Emergencies Body Temperature • Normal body temperature is 98.6ºF. • Body attempts to maintain normal temperature despite ambient temperature. • Body cools itself by sweating (evaporation) and dilation of blood vessels. • High temperature and humidity decrease effectiveness of cooling mechanisms. 53 Chapter 15: Environmental Emergencies Hyperthermia (1 of 2) • Core temperature > 101°F (38°F) • Cooling mechanisms become overwhelmed and the body is unable to cope. • Illnesses can develop when: – Air temp is high – Humidity is high – Dehydration curtails the ability to sweat 54 Chapter 15: Environmental Emergencies Hyperthermia (2 of 2) • Predisposing risk factors include: – – – – – Extremes of age Poor thermoregulation Heart disease, COPD, diabetes, and obesity Limited mobility Drug and alcohol abuse 55 Chapter 15: Environmental Emergencies Heat Cramps • Painful muscle spasms • Remove the patient from hot environment. • Rest the cramping muscle. • Replace fluids by mouth. • If cramps persist, arrange for transport to hospital. 56 Chapter 15: Environmental Emergencies Heat Exhaustion • Onset while working hard or exercising in hot environment • In elderly and young, onset may occur while at rest in hot, humid, and poorly ventilated areas. • Signs and symptoms: – Cold, clammy skin – Dry tongue and thirst 57 Chapter 15: Environmental Emergencies Heat Exhaustion: Signs and Symptoms • Normal vital signs, but pulse can increase and blood pressure can decrease. • Dizziness, weakness, or fainting • Normal or slightly elevated body temperature 58 Chapter 15: Environmental Emergencies Emergency Care for Heat Exhaustion • Remove extra clothing, remove patient from hot environment. • Give patient oxygen. • Have patient lie down and elevate legs. • If patient is alert, give water or diluted electrolyte solution slowly. • Be prepared to transport. 59 Chapter 15: Environmental Emergencies Heatstroke • Signs and symptoms: – Hot, dry, flushed skin – Change in behavior leading to unresponsiveness – Pulse rate is rapid, then slows. – Blood pressure drops. – Death can occur if the patient is not treated. 60 Chapter 15: Environmental Emergencies Emergency Care for Heatstroke (1 of 2) • Move patient out of the hot environment. • Remove the patient’s clothing. • Administer oxygen. • Apply cold packs to the patient’s neck, armpits, and groin. 61 Chapter 15: Environmental Emergencies Emergency Care for Heatstroke (2 of 2) • Cover the patient with wet towels or sheets. • Aggressively fan the patient. • Immediately transport patient. • Notify hospital of patient’s condition. 62 Chapter 15: Environmental Emergencies Lightning and Electrical Injury • • • • • Significant hazard 1,000 deaths annually 100 to 200 due to lightning Power transmission lines are widespread. Outdoor activities in the spring and summer increase the risk of lightning strike. 63 Chapter 15: Environmental Emergencies Electrical Injury (1 of 2) • Insult to respiratory centers that lead to respiratory arrest • Cardiac arrest – AC current = V-fib – DC current = asystole • Severe burns to skin, muscle, bone, and organs – Can produce large and devastating burns 64 Chapter 15: Environmental Emergencies Electrical Injury (2 of 2) • Direct injury to nerves that lead to pain, paralysis, blindness, deafness, and loss of speech • Kidney overload and injury due to toxic concentrations of waste • Falls due to loss of balance or muscle contractions 65 Chapter 15: Environmental Emergencies Lightning Injury • Lightning is usually associated with cumulonimbus clouds (thunderheads). • Can occur during snowstorm • 30% fatality rate with strikes • Victims may display a characteristic burn pattern that is fern shaped. • Can be direct strike or by conducted current 66 Chapter 15: Environmental Emergencies Emergency Care for Electrical Injury (1 of 3) • Rescue may require special training and equipment; protect yourself. • Remove the victim from the electrical source. • Those trapped in vehicles will need to jump clear to avoid being grounded. 67 Chapter 15: Environmental Emergencies Emergency Care for Electrical Injury (2 of 3) • Don’t touch victims until live wires are clear. • Start CPR immediately in the case of cardiac arrest. • During triage, these patient (electrical injury) should be cared for first. 68 Chapter 15: Environmental Emergencies Emergency Care for Electrical Injury (3 of 3) • Be prepared for: burns, fractures, multiple trauma, neck, and spinal injuries. • Provide high-flow oxygen. • Pulses may return, but patients may require lengthy respiratory support. • Provide assessment, stabilization, and evacuation consistent with trauma care. 69 Chapter 15: Environmental Emergencies Prevention of Electrical Injury (1 of 2) • Conductors transmit electricity and insulators resist electrical flow. • Electricity follows the path of least resistance. • Urban injuries usually involve appliances or accidental contact with power lines. 70 Chapter 15: Environmental Emergencies Prevention of Electrical Injury (2 of 2) • Avoid areas prone to lightning strike: – Bodies of water – Ridges, high points, and lone trees – Telephones and appliances – Small caves or wide open spaces – Large metal structures • Count seconds between lightning and thunder and divide by 5; the result is distance in miles. 71 Chapter 15: Environmental Emergencies Drowning and Near Drowning • Drowning – Death as a result of suffocation after submersion in water • Near drowning – Survival, at least temporarily, after suffocation in water 72 Chapter 15: Environmental Emergencies Drowning Process (1 of 2) 73 Chapter 15: Environmental Emergencies Drowning Process (2 of 2) • Small amounts of water can cause laryngospasm. • This may inhibit rescue breathing. • Hypoxia leads to unresponsiveness. • 85% to 90% involve significant amount of water in the victim’s lungs. 74 Chapter 15: Environmental Emergencies Emergency Medical Care • Begin rescue breathing as soon as possible. • Maintain cervical spine stabilization. • If air does not enter the patient’s lungs, treat for obstructed airway. • Check pulse and start CPR if needed. • Keep patient warm and transport. 75 Chapter 15: Environmental Emergencies Spinal Injuries in Submersion Incidents • Suspect spinal injury if: – Submersion has resulted from a diving mishap or long fall. – Patient is unresponsive. – Patient complains of weakness, paralysis, or numbness. 76 Chapter 15: Environmental Emergencies Water Rescuer Safety • • • • • Protect yourself! “Reach, throw, row, and only than go” Wear a personal flotation device (pfd). Guard against hypothermia. When working on or near water, develop a pre-arranged rescue plan. 77 Chapter 15: Environmental Emergencies Spinal Stabilization in Water • Turn the patient supine. • Restore the airway and begin ventilations. • Secure a backboard under the patient. • Remove the patient from the water. • Cover the patient with a blanket. 78 Chapter 15: Environmental Emergencies Resuscitation Efforts • Hypothermia can protect vital organs from hypoxia. • Documented case of a survivor of a 66minute cold water submersion • Diving reflex may cause heart rate to slow. 79 Chapter 15: Environmental Emergencies Avalanche Injuries (1 of 2) • Fatalities: – 80% - asphyxia – 10% to 15% - trauma – 5% - hypothermia • 92% survival rate if uncovered within 15 minutes • By 35 minutes, only 30% survive. 80 Chapter 15: Environmental Emergencies Avalanche Injuries (2 of 2) • Best chance of survival is by companion rescue. • Most victims are backcountry skiers, snowboarders, climbers, and snowmobile riders. • Backcountry users should be trained and carry: – Shovel – Avalanche probe – Avalanche transceiver 81 Chapter 15: Environmental Emergencies Emergency Care for Avalanche Victims • Uncover head and chest quickly and carefully. • Treat for hypothermia. • Provide high-flow oxygen. • Assess and treat for trauma. 82 Chapter 15: Environmental Emergencies Ice Rescue • Is very hazardous • Cold water can incapacitate victims quickly. • Use personal flotation devices (pfd). • Use ladders or objects to distribute weight. • Self-rescue with sharp tipped objects or by rolling • Remove skis or snowboard. • Assess and treat hypothermia. 83 Chapter 15: Environmental Emergencies Diving Problems • Descent problems – Usually due to the sudden increase in pressure on the body as the person dives • Bottom problems – Not commonly seen • Ascent problems – Air embolism and decompression sickness 84 Chapter 15: Environmental Emergencies Signs and Symptoms of Air Embolism (1 of 2) • Blotchy skin • Froth at the mouth and nose • Severe pain in muscle, joints, or abdomen • Dyspnea and/or chest pain 85 Chapter 15: Environmental Emergencies Signs and Symptoms of Air Embolism (2 of 2) • Dizziness, nausea, and vomiting • Dysphasia • Difficulty with vision • Paralysis and/or coma • Irregular pulse or cardiac arrest 86 Chapter 15: Environmental Emergencies Decompression Sickness (The Bends) • Occurs when bubbles of gas obstruct blood vessels • Can result from rapid ascent • Most common symptom is abdominal and/or joint pain. • Symptoms may develop after several hours. 87 Chapter 15: Environmental Emergencies Caring for Air Embolism and Decompression Sickness • • • • Remove the patient from the water. Keep patient calm. Begin BLS and administer oxygen. Place the patient in the left lateral recumbent position with his or her head down. • Provide prompt transport to hyperbaric chamber. 88 Chapter 15: Environmental Emergencies Other Water Hazards • Hypothermia from water immersion. • Breath-holding syncope • Swimmer’s ear • Injuries from recreational equipment or marine animals 89