CFRN Environmental and Toxicological Emergencies 3 — Questions and Answers
Question 1: A construction worker collapsed after working in a confined space. Bystanders report the smell of rotten eggs. Which immediate action is most important for the flight crew's safety?
- Enter immediately and begin CPR
- Don self-contained breathing apparatus before approaching the patient (Correct answer)
- Administer oxygen to the patient from a distance
- Call for hazmat support and wait indefinitely
Correct answer: Don self-contained breathing apparatus before approaching the patient
Hydrogen sulfide is immediately dangerous to life; crew must use SCBA before entering the space to avoid becoming secondary victims.
Question 2: During air transport, a patient with severe hypothermia (core temp 28°C) develops ventricular fibrillation. After the first defibrillation attempt fails, what is the most appropriate next action?
- Continue repeated defibrillation attempts every 2 minutes
- Administer amiodarone and continue CPR while actively rewarming
- Withhold further defibrillation until core temperature exceeds 30°C (Correct answer)
- Increase defibrillation energy to maximum immediately
Correct answer: Withhold further defibrillation until core temperature exceeds 30°C
Below 30°C, the hypothermic heart is refractory to defibrillation; current guidelines recommend withholding additional shocks until rewarming achieves at least 30°C.
Question 3: A child ingested an unknown mushroom in the woods. The child now has excessive salivation, lacrimation, urination, defecation, and bronchospasm. Which mushroom toxidrome is this consistent with?
- Amanita phalloides (phalloidin toxidrome)
- Muscarine toxidrome (e.g., Clitocybe or Inocybe species) (Correct answer)
- Gyromitrin toxidrome
- Ibotenic acid toxidrome
Correct answer: Muscarine toxidrome (e.g., Clitocybe or Inocybe species)
The SLUDGE/DUMBELS constellation of symptoms represents cholinergic excess consistent with muscarine-containing mushrooms.
Question 4: A patient exposed to chlorine gas at an industrial accident arrives with coughing, wheezing, and conjunctival irritation. What is the priority airway management concern specific to chlorine inhalation?
- Immediate orotracheal intubation regardless of current status
- Anticipate delayed pulmonary edema up to 24 hours after exposure (Correct answer)
- Administer sodium bicarbonate nebulization as primary treatment
- Expect the symptoms to resolve without intervention within 1 hour
Correct answer: Anticipate delayed pulmonary edema up to 24 hours after exposure
Chlorine gas exposure can cause delayed-onset pulmonary edema hours after initial exposure, requiring prolonged monitoring even in initially stable patients.
Question 5: A mountaineer is being evacuated with acute mountain sickness and is unable to descend. Which pharmacological agent is most effective for preventing progression to HACE?
- Dexamethasone
- Acetazolamide (Correct answer)
- Nifedipine
- Furosemide
Correct answer: Acetazolamide
Acetazolamide accelerates acclimatization by stimulating increased ventilation and is the primary pharmacological prophylaxis and treatment for AMS/HACE.
Question 6: While transporting a patient after a brown recluse spider bite, which systemic complication is most concerning in the first 24–72 hours?
- Immediate anaphylactic shock
- Hemolysis, DIC, and acute renal failure (Correct answer)
- Neurotoxic respiratory failure
- Compartment syndrome of the bite extremity
Correct answer: Hemolysis, DIC, and acute renal failure
Loxoscelism (systemic brown recluse envenomation) can cause intravascular hemolysis, disseminated intravascular coagulation, and subsequent renal failure.
Question 7: A patient arrives with suspected iron overdose. After stabilization, which antidote is used for significant iron toxicity?
- Calcium EDTA
- Deferoxamine (Correct answer)
- Dimercaprol (BAL)
- Succimer (DMSA)
Correct answer: Deferoxamine
Deferoxamine is a chelating agent that binds free iron to form ferrioxamine, which is then renally excreted, and is the specific antidote for iron toxicity.
CFRN Environmental and Toxicological Emergencies 3
A construction worker collapsed after working in a confined space.
Bystanders report the smell of rotten eggs.
Which immediate action is most important for the flight crew's safety?