Environmental and Toxicological Emergencies Flashcards

A patient presents with altered mental status, tachycardia, diaphoresis, and hyperthermia after exposure to an organophosphate insecticide. Which antidote should be administered first?

Answer: Atropine

Atropine is the first-line antidote for organophosphate poisoning as it blocks muscarinic effects; pralidoxime should follow but atropine takes priority.

During flight transport of a patient with suspected carbon monoxide poisoning, the pulse oximeter reads 98%. What is the most accurate interpretation?

Answer: Pulse oximetry is unreliable because it cannot differentiate oxyhemoglobin from carboxyhemoglobin

Standard pulse oximetry cannot distinguish carboxyhemoglobin from oxyhemoglobin, so it may falsely appear normal despite severe CO poisoning.

A hiker rescued from a high-altitude environment develops pulmonary edema at 14,000 feet. What is the most appropriate initial intervention?

Answer: Descend immediately and administer supplemental oxygen

Immediate descent combined with supplemental oxygen is the definitive treatment for high-altitude pulmonary edema (HAPE).

A patient was stung by multiple Africanized honeybees and is now showing signs of anaphylaxis. After administering epinephrine, which additional medication is most critical in flight?

Answer: IV corticosteroids and IV antihistamines

IV corticosteroids and antihistamines are used after epinephrine to prevent biphasic anaphylaxis and reduce ongoing inflammatory response.

A patient with tricyclic antidepressant (TCA) overdose develops a wide QRS complex and hypotension. What is the treatment of choice?

Answer: Sodium bicarbonate IV bolus

Sodium bicarbonate alkalinizes the serum and reverses TCA-induced sodium channel blockade, narrowing the QRS and improving hemodynamics.

While transporting a patient with suspected cyanide poisoning from an industrial fire, which finding most specifically suggests cyanide toxicity over simple CO poisoning?

Answer: Elevated venous oxygen saturation with profound metabolic acidosis

Cyanide inhibits cellular respiration causing elevated venous pO2 (cells cannot use oxygen) along with severe lactic acidosis.

A patient is brought in after ingesting a large quantity of acetaminophen 4 hours ago. Which laboratory value is most important to guide treatment decisions?

Answer: Serum acetaminophen level plotted on the Rumack-Matthew nomogram

The Rumack-Matthew nomogram uses a timed serum acetaminophen level (4–24 hours post-ingestion) to determine whether N-acetylcysteine is indicated.