Dyshemoglobinemias

Question 1

What is used to prevent lipid preoccupation and delayed neurologic sequelae in CO poisoning?

Answer 1

Hyperbaric oxygen

Question 2

Turns RBC Hb to methemoglobin…

Answer 2

Nitrites

Question 3

What is the mechanism of action of nitrites?

Answer 3

Turns RBC Hb to methemoglobin–CN moves from Fe(3+) on cytochromes to those in RBCs creating cyanomethemoglobin

Question 4

What should not be given in concurrent CO poisoning?

Answer 4

Nitrites

Question 5

Enhances normal metabolism of cyanide via rhodanase…

Answer 5

Sodium thiosulfate

Question 6

Binds with cyanide–> cyanocobalamin (B12)

Answer 6

Hydroxycobalamin

Question 7

What is hydroxycobalamin used for?

Answer 7

Smoke inhalation victims not improving with supportive care
cyanide exposure
nitroprusside at risk patients

Question 8

What is tydroxycobalamin given concurrently with?

Answer 8

Sodium thiosulfate

Question 9

Cofactor of NADPH reductase; gains electron, donates directly to reduce methemoglobin

Answer 9

Methylene blue

Question 10

What is methylene blue used for?

Answer 10

Methemoglobinemia > 20-30% or when symptoms occur

Question 11

What are the side effects of methylene blue?

Answer 11

Hemolytic anemia
painful at injection site
dyspnea
restlessness
tremor
precordial pain
apprehension