WonkyHonky69

WonkyHonky69 t1_j1xa9b0 wrote

This is probably not the reason. As much as I’m aware, the red hair anesthetic resistance was tested discovered for inhalational anesthetics, which do not have the same mechanisms of action as local anesthetics.

The real answer to your question could probably better be answered by an attending anesthesiologist (I’m only an intern), but you’re asking hours vs days as if all nerve blocks are created equal. They are not. Some local anesthetics last longer than others and there is an element of proceduralist dependence (in the case of a few hours vs 24 hours like OP stated). What the other commenter was talking about (weeks) is almost certainly a steroid injection, which is intended to reduce inflammation around the nerve, which will indeed last weeks. A local anesthetic nerve block for a surgery will not.

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