Dyshemoglobinemias Flashcards
Name the 5 treatments of hemoglobinemias
Hyperbaric Oxygen, Nitrites, Sodium Thiosulfate, Hydroxycobalamin, and Methylene Blue
What is hyperbaric oxygen treatment used for?
to prevent lipid peroxidation and delayed neuro. sequlae in CO poisoning; need it at >2atm
What is the mechanism for nitrite treatment?
turns RBC hemoglobin into methemoglobin
In what situations are nitrites more dangerous?
with concurrent CO poisoning
What is the mechanism of sodium thiosulfate?
Enhances normal metabolism of cyanide via rhodanase
What is the mechanism of hydroxycobalamin?
binds with cyanide to form cyanocobalamin (vitamin B12)
When is hydroxycobalamin indicated for use?
smoke inhalation victims that aren’t improving, cyanide exposure, nitroprusside at risk patients
What other drug is hydroxycobalamin given with?
sodium thiosulfate
What is the mechanism of action for methylene blue?
it’s a cofactor of NADPH reductase; it gains an electron and donates it to reduce methemoglobin
When is methylene blue given?
With methemoglobinemia >20-30% or with symptoms
What are the side effects of methylene blue?
hemolytic anemia, pain at injection site, dyspnea, restlessness, tumor, and precordial pain
Which 3 drugs are used to treat Cyanide poisoning?
Nitrites, Sodium thiosulfate and hydroxycobalamin
Is the oxygen saturation on pulse oximetry low, normal or high in CO poisoning?
falsely normal (because carboxyhemoglobin is read as oxyhemoglobin)
What are the possible scenarios for a patient who is not responding to methylene blue treatment?
Hemoglobin M diseases, G6PD Deficiency, CL salts that inactivate G6PD, sulfhemoglobinemia or a wrong diagnosis
