CPEN CPEN Toxicology and Poisoning Emergencies 4 — Questions and Answers
Question 1: A 3-year-old ingested iron supplement tablets. Which early clinical sign is MOST associated with iron toxicity in the gastrointestinal phase?
- Bradycardia and hypotension
- Hematemesis and bloody diarrhea (Correct answer)
- Seizures and altered mental status
- Metabolic alkalosis
Correct answer: Hematemesis and bloody diarrhea
Iron is directly corrosive to the GI tract, causing hematemesis, bloody diarrhea, and abdominal pain in the initial GI phase of toxicity.
Question 2: Which antidote is indicated for severe iron poisoning in a pediatric patient?
- N-acetylcysteine
- Deferoxamine (Correct answer)
- Flumazenil
- Atropine
Correct answer: Deferoxamine
Deferoxamine chelates free iron in the blood, forming ferrioxamine which is excreted renally, and is the antidote for severe iron toxicity.
Question 3: A teenager presents with altered mental status, hyperthermia, tachycardia, and mydriasis after ingesting an unknown substance. These findings are MOST consistent with which toxidrome?
- Cholinergic
- Sympathomimetic (Correct answer)
- Opioid
- Sedative-hypnotic
Correct answer: Sympathomimetic
Sympathomimetic toxidrome is characterized by hyperthermia, tachycardia, hypertension, mydriasis, and agitation due to excess catecholamine activity.
Question 4: A 5-year-old is brought in after ingesting a button battery. Which complication is the MOST serious concern if the battery is lodged in the esophagus?
- Aspiration pneumonia
- Esophageal perforation from liquefactive necrosis (Correct answer)
- Methemoglobinemia
- Bowel obstruction
Correct answer: Esophageal perforation from liquefactive necrosis
Button batteries lodged in the esophagus generate hydroxide ions via electrical current, causing rapid liquefactive necrosis that can perforate the esophagus within 2 hours.
Question 5: An 8-year-old ingested a large amount of acetaminophen 6 hours ago. The MOST important laboratory test to guide antidote therapy at this time is:
- Liver function tests (AST/ALT)
- Serum acetaminophen level plotted on the Rumack-Matthew nomogram (Correct answer)
- Serum creatinine
- Complete blood count
Correct answer: Serum acetaminophen level plotted on the Rumack-Matthew nomogram
The serum acetaminophen level drawn 4 or more hours post-ingestion and plotted on the Rumack-Matthew nomogram determines the risk of hepatotoxicity and the need for N-acetylcysteine.
Question 6: A 2-year-old presents with a serum ethanol level of 80 mg/dL after ingesting mouthwash. Which complication requires PRIORITY monitoring in young children with ethanol ingestion?
- Metabolic acidosis with elevated anion gap
- Hypoglycemia (Correct answer)
- Respiratory alkalosis
- Hypertension
Correct answer: Hypoglycemia
Young children are at high risk for ethanol-induced hypoglycemia because they have limited glycogen stores and ethanol inhibits gluconeogenesis.
Question 7: Which of the following household products contains hydrocarbons and poses the GREATEST risk of aspiration pneumonitis in children?
- Bleach (sodium hypochlorite)
- Gasoline or lamp oil (Correct answer)
- Isopropyl alcohol
- Hydrogen peroxide
Correct answer: Gasoline or lamp oil
Low-viscosity hydrocarbons like gasoline and lamp oil have a high aspiration potential due to their low surface tension, spreading easily into the lungs and causing pneumonitis.
CPEN CPEN Toxicology and Poisoning Emergencies 4
A 3-year-old ingested iron supplement tablets.
Which early clinical sign is MOST associated with iron toxicity in the gastrointestinal phase?