[09.22.2023] Updated content, AnKing Overhaul for Step 1 & 2/AnKingMed, ID 708449

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@Ahmed7 @thomas.holmes @shmuelsash @Sameem - thought this would be easy to resolve, ended up in a rabbit hole. According to the card on neurogenic shock & the corresponding UW table, SvO2 is decreased in neurogenic shock, so it wouldn’t be true to say that all distributive shock results in increased SvO2. Checked with AMBOSS, they says SvO2 is normal or increased in neurogenic shock. I have no idea which is correct, but that impacts whether or not we change this card.

Ya that’s bit difficult. There are multiple QID tags - Step 2: 6990. Step 1: 21505, 13979. I can’t check these QIDs but maybe see if the UW explanations mention neurogenic shock?

It is decreased or remains same in neurogenic shock. The mechanism of high svo2 in septic shock is that the peripheral cells (after microvascular and mitochondrial damage) are unable to extract oxygen from blood, which clearly isn’t the case in neurogenic. Also high output from heart in case of distributive shocks increases svo2 by some amount, but that is minimal in case of neurogenic shock as cardiac output isn’t able to rise much (sympathetic stimulation is decreased).

@thomas.holmes those QIDs are about other types of shock - the only mention of neurogenic is just what I put above unofrtunately.

@Sameem that makes sense, but I was reading that the loss of sympathetic tone results in persistent vasodilation → hyperdynamic circulation → impaired O2 extraction → increased SvO2

Maybe that happens early on in the shock? I’ve never personally seen someone with neurogenic shock but I’ve always read that svo2 decreases. Vasodilation shouldn’t affect O2 extraction since tissues are functional? I think we should go with UWorld and add the note on amboss in extra section. @herstein.jacob

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