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Phenytoin is itself arrhythmogenic.
What's the question, and is bicarbonate the answer?
Page 2!
What's the question, and is bicarbonate the answer?
Page 2!
Phenytoin is itself arrhythmogenic.
Page 2!
well the reason xiphoid was wrong is that phenytoin isn't effective for drug-induced seizures. Benzos, benzos, benzos are.
Glucagon isn't used for TCA overdose, but in the case presented to us, high-dose insulin was used successfully. Glucagon is usually used for Beta-Blocker overdoses and high-dose insulin was first used for calcium channel blockers.
Sodium Bicarbonate works by both alkalinizing the serum, which decreases the affinity of the TCA for the cardiac sodium channels, and providing a sodium load, thereby flooding the sodium channels.
For a patient who is alkalotic from too much bicarb there are case reports (the big one is from my alma mater) of using hypertonic saline and hyperventilation, so you can titrate the alkalinity and sodium separately. But that is not common practice.
For once I was not on my phone and could actually answer things.
NE is b/c TCA's induced alpha blockade and bp drop in OD. Dopa will not work (unless you crank the rate up to at leat 15-20 mcg/kg/min, which then they will start tachying away and induce some other type of arrhthymia)-plus you've depleted your indogenous resevere of dopa to initiate the relase of your own NE). NE is the most most potent alpha agonist to help with hypotension. Bicarb is because of the QRS widening affect of TCA's and has nothing to do with the bicarb componet but the NA content, b/c if you are blocking Na+ channesl with the TCA, in theory, giving Na+ will overcome that, hence even using NS is a viable option. Also phenytoin is never used. Drug OD's pretty much are gaba mediated, and bz can supress firing faster than Na+ channels that pheny works on.