Lightning Hazards, Wilderness Scene Safety, and Special Populations in Environmental Emergencies Practice Questions

25 multiple-choice questions on Lightning hazards, wilderness scene safety, and special populations in environmental emergencies for paramedic and EMT students, from Chapter 39 (Environmental Emergencies). Read each question, pick your answer, then tap Show answer to check it and read the explanation.

25 practice questions

1. The most common mechanism of lightning injury is:

   1. A. A direct strike to the top of the victim's head
   2. B. Burns from clothing that catches on fire
   3. C. Ground current spreading from the strike point
   4. D. A blast wave from the thunder clap itself
   Show answer

   Answer: C. Ground current spreading from the strike point

   Most lightning injuries come from ground current and side flash rather than direct strikes, which is why groups standing near a strike can all be hurt. Direct strikes are the least common but most lethal mechanism.

2. A side flash (splash) lightning injury occurs when:

   1. A. Current travels up from the ground through the feet
   2. B. A person is holding a metal object during the strike
   3. C. Thunder ruptures the eardrum during a storm
   4. D. Current jumps from a struck object to a person
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   Answer: D. Current jumps from a struck object to a person

   Lightning striking a tree or pole can arc to a person standing nearby, which is why sheltering under trees is dangerous. Ground current, by contrast, spreads through the earth.

3. Which location offers the best protection from lightning during a thunderstorm?

   1. A. A picnic shelter with an open metal roof
   2. B. An enclosed building with wiring and plumbing
   3. C. A dry tent in a meadow at the treeline
   4. D. Beneath the tallest tree in a dense stand of pines
   Show answer

   Answer: B. An enclosed building with wiring and plumbing

   Substantial buildings and hard-topped metal vehicles conduct current around the occupants. Open shelters, tents, and isolated trees give no meaningful protection.

4. A crew is working an outdoor call and hears distant thunder, though no rain has started. You should:

   1. A. Move everyone into vehicles or a building
   2. B. Continue working until the rain begins
   3. C. Kneel the crew under the nearest large tree
   4. D. Wait for the storm to be directly overhead
   Show answer

   Answer: A. Move everyone into vehicles or a building

   NOAA teaches "When thunder roars, go indoors": if you can hear thunder, you are close enough to be struck, and lightning often strikes well ahead of the rain. The older 30-second flash-to-bang count is no longer used to decide when to take shelter.

5. After a thunderstorm passes, outdoor activity can safely resume:

   1. A. As soon as the rain has stopped
   2. B. When the sun first appears again overhead
   3. C. 30 minutes after the last thunder
   4. D. 5 minutes after the last flash
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   Answer: C. 30 minutes after the last thunder

   Lightning can strike many kilometers from the trailing edge of a storm, so the guideline is to wait 30 minutes after the last thunder. Clearing skies and the end of rain do not mean the threat has passed.

6. Hikers caught in the open with lightning nearby and no shelter should:

   1. A. Spread out and avoid peaks and open fields
   2. B. Crouch together in one tight group on the ground
   3. C. Lie flat on the ground in an open meadow
   4. D. Shelter under a lone tall tree
   Show answer

   Answer: A. Spread out and avoid peaks and open fields

   Spreading out at least 15 m (50 ft) apart reduces the chance of multiple victims, and moving off ridges and out of open terrain lowers risk. Lying flat increases contact with ground current, a tight group invites several victims from one strike, and a lone tall tree attracts strikes and side flash.

7. A lightning victim in respiratory arrest has fixed, dilated pupils. Regarding resuscitation, this finding:

   1. A. Proves that he has died
   2. B. Limits CPR to about 5 minutes
   3. C. Should not stop the effort
   4. D. Moves him to the lowest triage priority
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   Answer: C. Should not stop the effort

   Lightning can cause temporary autonomic dysfunction, producing fixed, dilated pupils in patients who can still recover. Pupil findings should not be used to withhold or stop resuscitation in lightning victims, who often survive with prompt ventilation and CPR. In lightning incidents, reverse triage puts apneic or pulseless victims first because they are the ones who can be saved, and there is no 5-minute limit.

8. Survivors of lightning strike most often have:

   1. A. Deep entry and exit burns needing amputation
   2. B. Massive internal bleeding along the current path
   3. C. Kidney failure from widespread muscle injury
   4. D. Ruptured eardrums and transient neurologic deficits
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   Answer: D. Ruptured eardrums and transient neurologic deficits

   Lightning current is brief and mostly flashes over the surface, so deep burns and rhabdomyolysis are uncommon compared with high-voltage injury. Tympanic membrane rupture, confusion, and amnesia are common.

9. A lightning victim found in a field during a storm has a deformed forearm and is confused. The scene is still active. Your first action is to:

   1. A. Splint the forearm where he lies first
   2. B. Move him to a safer location before care
   3. C. Complete a head-to-toe assessment first
   4. D. Wait for the storm to pass before entering
   Show answer

   Answer: B. Move him to a safer location before care

   Lightning can strike the same place twice, so if the storm is ongoing, move the patient and crew to shelter, then treat. The victim carries no charge and can be touched immediately.

10. In wilderness EMS, extended patient care is needed mainly because:

    1. A. Wilderness patients are sicker than urban ones
    2. B. Hospital protocols do not apply outdoors
    3. C. Rescuers must work alone on these calls
    4. D. Evacuation to definitive care may take hours
    Show answer

    Answer: D. Evacuation to definitive care may take hours

    Long evacuation times shift the focus to prolonged monitoring, wound care, warming, hydration, and decisions such as reducing dislocations or stopping CPR. The setting, not patient severity, drives these needs.

11. A wilderness provider decides whether to evacuate a patient on foot or call for a helicopter. The decision should weigh:

    1. A. The patient's condition alone
    2. B. Patient condition, terrain, weather, and risk
    3. C. The fastest option, whatever the weather or risk
    4. D. The distance to the trailhead
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    Answer: B. Patient condition, terrain, weather, and risk

    Evacuation planning balances the urgency of the patient's condition (and the patient's informed wishes) against the time and hazards of each option for both the patient and the rescuers, including terrain, weather, daylight, and available people. A helicopter may be unsafe in poor weather or high winds, and a long carry may be too slow for a time-critical illness. Looking at the patient's condition alone ignores the hazards to the team, choosing speed regardless of weather can make the evacuation itself the danger, and distance by itself says nothing about terrain or the patient's stability. (WMS/NAEMSP wilderness EMS joint project 2017.)

12. Children are more vulnerable than adults to heat illness in part because they:

    1. A. Have a higher blood volume per kg than adults
    2. B. Sweat more heavily than adults do in heat
    3. C. Have more surface area per kg and sweat less
    4. D. Acclimatize to heat within one day
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    Answer: C. Have more surface area per kg and sweat less

    A larger surface area relative to mass makes children gain heat faster in hot surroundings, and they produce less sweat and depend on adults for fluids and shade. They acclimatize more slowly, not faster.

13. A 2-year-old was left in a parked car on a 32°C (90°F) day for 40 minutes. He is lethargic and hot. The most important point is that:

    1. A. A closed car heats rapidly even with windows cracked
    2. B. Cracking a window keeps the inside temperature safe
    3. C. Cars heat slowly, so 40 minutes is not dangerous
    4. D. Car heat illness needs air above 38°C (100°F)
    Show answer

    Answer: A. A closed car heats rapidly even with windows cracked

    Interior temperatures can rise about 10°C (20°F) within 10 minutes and climb above 50°C (122°F), even with windows partly open. Pediatric vehicular heat stroke can occur on mild days.

14. Older adults are at increased risk for hypothermia because of:

    1. A. Greater muscle mass and a higher metabolic rate
    2. B. A stronger shivering response than the young
    3. C. Reduced shivering and impaired vasoconstriction
    4. D. Faster heart rates that protect in the cold
    Show answer

    Answer: C. Reduced shivering and impaired vasoconstriction

    Aging blunts the perception of cold, shivering, and vasoconstriction, and chronic illness, medications, and limited mobility add risk. Older adults also have less muscle mass, which reduces heat production. Shivering weakens rather than strengthens with age, and the heart rate does not rise to protect against cold.

15. A 15-year-old football player is in the first week of preseason practice in August. His greatest risk factor for exertional heat stroke is:

    1. A. Wearing a mouth guard at practice
    2. B. Being an adolescent
    3. C. Practicing on a natural grass field
    4. D. Lack of heat acclimatization
    Show answer

    Answer: D. Lack of heat acclimatization

    Unacclimatized athletes in the first days of preseason, often in full equipment, are at highest risk, which is why acclimatization periods are recommended. Equipment that limits evaporation adds to the risk.

16. The wet bulb globe temperature (WBGT) used by athletic programs:

    1. A. Measures humidity but ignores sunlight and wind
    2. B. Combines temperature, humidity, sun, and wind
    3. C. Combines air temperature and humidity like the heat index
    4. D. Uses temperature and sun but not humidity
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    Answer: B. Combines temperature, humidity, sun, and wind

    WBGT reflects the total heat stress on the body by combining air temperature (dry bulb), humidity and air movement (natural wet bulb), and radiant heat from the sun (black globe). Practices are modified or canceled as WBGT rises. It does include humidity, but the globe and wet-bulb readings also capture sunlight and wind, so it does not ignore them. Temperature and humidity alone make up the heat index, which leaves out sun and wind, and a reading without humidity misses the main limit on sweat evaporation. (ACSM 2023 exertional heat illness consensus.)

17. Which medication group increases heat production and the risk of heat stroke?

    1. A. Sympathomimetics such as amphetamines
    2. B. Loop diuretics such as furosemide
    3. C. Beta-blockers such as metoprolol tartrate
    4. D. ACE inhibitors such as lisinopril
    Show answer

    Answer: A. Sympathomimetics such as amphetamines

    Stimulants raise metabolic heat production and muscle activity while impairing judgment. Diuretics and beta-blockers impair heat loss rather than adding heat.

18. A teenager with cystic fibrosis plays soccer on a hot day and becomes weak and nauseated. He is especially prone to heat illness because his sweat:

    1. A. Contains less salt than normal sweat
    2. B. Is mostly potassium, not salt
    3. C. Is thicker and blocks his sweat glands
    4. D. Loses much more salt than normal
    Show answer

    Answer: D. Loses much more salt than normal

    In cystic fibrosis, defective chloride channels cause very salty sweat, so these patients lose large amounts of sodium in the heat and can develop dehydration and hyponatremia. They need extra salt and fluids. Their sweat contains more, not less, sodium chloride, it is not mainly potassium, and the thick secretions of CF affect the lungs and pancreas rather than blocking the sweat glands.

19. A homeless man is found asleep outdoors on a cold, wet night. He is at high risk for hypothermia because of:

    1. A. High body fat and a raised metabolic rate
    2. B. Exposure, wet clothing, poor nutrition, and alcohol
    3. C. Constant exercise that keeps his core warm
    4. D. Strong shivering built up by years of regular cold exposure
    Show answer

    Answer: B. Exposure, wet clothing, poor nutrition, and alcohol

    Homelessness combines prolonged exposure, wet clothing, malnutrition, alcohol or drug use, and chronic illness. These factors reduce heat production and increase heat loss.

20. A 55-year-old with diabetic neuropathy walked through snow without noticing numb feet. The neuropathy raises his frostbite risk because it:

    1. A. Raises his body's heat production
    2. B. Causes his feet to sweat less in the cold
    3. C. Impairs sensation and local blood flow
    4. D. Thickens the skin on the soles
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    Answer: C. Impairs sensation and local blood flow

    Neuropathy prevents the warning of cold and pain, and diabetic vascular disease reduces blood flow. Patients may not notice frostbite until it is advanced.

21. A pregnant woman at 30 weeks is hiking in hot weather. Compared with nonpregnant women, she is at greater risk of heat illness because:

    1. A. Her metabolic heat production is higher
    2. B. Her core temperature is set much lower
    3. C. She sweats more efficiently in humidity
    4. D. Her blood volume is lower than normal
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    Answer: A. Her metabolic heat production is higher

    Pregnancy increases metabolic rate and heat production, and dehydration reduces uterine perfusion. Blood volume actually rises in pregnancy.

22. An 80-year-old man fell and has lain on the floor of a warm room for 24 hours. His temperature is 35°C (95°F). This finding most likely suggests:

    1. A. Heat exhaustion from the warm room
    2. B. A thermometer error to be ignored
    3. C. A normal temperature for his age group
    4. D. Impaired thermoregulation from illness
    Show answer

    Answer: D. Impaired thermoregulation from illness

    Older adults can become hypothermic even indoors: they produce less heat (less muscle mass, immobility after a fall), shiver and vasoconstrict less, and are often hypothermic because of an illness such as sepsis, stroke, hypothyroidism, or hypoglycemia, or because of medications. A low reading after a long lie should prompt a search for the cause. Heat exhaustion produces a normal or raised temperature, not a low one. A suspicious reading should be rechecked with a core-reading method, not ignored. Average temperature runs only slightly lower in older adults, so 35°C (95°F) is not normal at any age. (Caroline 9th ed., Environmental Emergencies; WMS 2019 hypothermia update.)

23. Which patient is at highest risk for environmental heat illness during a heat wave?

    1. A. A 30-year-old working in an air-conditioned office
    2. B. A teenager swimming at a public pool
    3. C. A bedridden man taking an antipsychotic
    4. D. A 45-year-old resting at home with a fan and AC
    Show answer

    Answer: C. A bedridden man taking an antipsychotic

    Immobility prevents escape from heat, and antipsychotics impair sweating and the hypothalamic response. Air conditioning is the single most protective factor during heat waves.

24. Wilderness protocols allow stopping CPR after about 20 to 30 minutes in a normothermic patient with no response because:

    1. A. Brain death is certain by that point
    2. B. Prolonged CPR rarely helps and risks rescuers
    3. C. Drugs and shocks no longer work after that time
    4. D. The AED battery is drained by then
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    Answer: B. Prolonged CPR rarely helps and risks rescuers

    In the backcountry, CPR in a normothermic arrest that has not responded after about 20 to 30 minutes almost never leads to survival, and continuing it exhausts rescuers, delays evacuation, and exposes the team to terrain and weather. It is not that brain death is certain by then: cold, lightning, and drowning victims can survive much longer arrests, which is why they are exceptions where longer efforts are warranted. Drugs and defibrillation do not stop working at a fixed time, and the decision is not about equipment running out; it weighs futility and rescuer safety. (WMS wilderness CPR teaching; NAEMSP termination-of-resuscitation rules.)

25. A 19-year-old college football player with sickle cell trait slumps to the ground during repeated sprints on a hot day. He is alert and talking, says his legs feel weak rather than cramped, and has a rectal temperature of 38.7°C (101.7°F). You should suspect:

    1. A. Exertional sickling
    2. B. Exertional heat stroke
    3. C. Heat cramps
    4. D. Exercise-associated hyponatremia
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    Answer: A. Exertional sickling

    Intense, sustained exertion such as repeated sprints, especially in heat, at altitude, or with dehydration, can make red cells sickle in an athlete with sickle cell trait. The sickled cells block blood flow in working muscle, and the athlete slumps with weakness, can still talk, and has a temperature that is not very high. It is a medical emergency that can lead to rhabdomyolysis, hyperkalemia, and sudden death: give high-flow oxygen, cool if hyperthermic, monitor the ECG, and transport rapidly. Exertional heat stroke requires CNS dysfunction with a core temperature usually above 40°C, and he is alert. Heat cramps cause painful, visibly locked muscles, not weakness. Exercise-associated hyponatremia follows prolonged events with overdrinking and causes confusion and nausea, not a sudden collapse during a short sprint drill. (NATA sickle cell trait consensus statement; NATA 2012 sudden death position statement.)