UWorld 3

Question 1

2 toxic compounds found in smoke inhalation? How to treat each?

Answer 1

CO - Causes carboxyhemoglobin. High flow O2, hyperbaric O2 if available

HCN - Hydrogen cyanide. Treat by inducing methemoglobinemia with nitrites. Or directly treated with hydroxycobalamin or sodium thiosulfate.

Question 2

How does methemoglobin form, drugs that cause this, and what signs may be seen?

Answer 2

Oxidation of iron in hemoglobin
Topical anesthetics and dapsone
Presents with hypoxia, pulse ox O2 sat of ~85% (due to characteristic color of methem), and large oxygen saturation gap (i.e. ABG saturation minus pulse Ox)

Question 3

Elevated Alk Phos and positive anti-mitochondrial antibody?

Answer 3

Primary biliary cholangitis
Jaundice, steatorrhea, hepatomegaly, eyelid xanthelasma, postal hypertension, osteopenia may develop
Tx: Ursodeoxycholic acid, hydrophilic bile acid that reduces injury from hydrophobic acids

Question 4

Risk in using nitroprusside over 24 hours? S/sx?

Answer 4

Cyanide toxicity, esp with kidney disease

S/sx: headache, confusion, arrhythmias, flushing, and respiratory distress.