Dyshemoglobinemias

Question 1

Hyperbaric oxygen

Answer 1

Therapeutics: Prevents lipid peroxidation and delayed neurologic sequelae in CO poisoning

Question 2

Nitrites

Answer 2

Class: N/a

Mechanism: Turns RBC hemoglobin to methemoglobin
CN moves from Fe3+ on cytochromes to those in RBCs creating cyanomethemoglobin

Therapeutics: Cyanide poisoning

Toxicity: Dangerous in concurrent CO poisoning

Question 3

Sodium thiosulfate

Answer 3

Class: N/A

Mech: Enhances normal metabolism of cyanide via rhodanase.

Therapeutics: Cyanide poisoning

Question 4

Hydroxycobalamin

Answer 4

Class: N/A

Mech: Binds with cyanide to become cyancobalamin (B12)

Therapeutics: Smoke inhalation victims that are not improving with supportive care indicating cyanide exposure.
Nitroprusside at risk patients

Toxicities: N/A

Misc. Give concurrently with sodium thiosulfate.

Question 5

Methylene Blue

Answer 5

Class: N/A

Mech: Cofactor of NADPH reductase so gains an electron and gives directly to reduce methemoglobin.

Therapeutics: Methemoglobinemia greater than 20-30% or with symptoms.

Toxicities: Hemolytic anemia (weak oxidizing capacity_
Painful at site of injection, dyspnea, restlessness, tremor, precordial pain, and apprehension.