Should we even learn the mechanism of how hypokalemia changes the ECG?

Ven0m

boop
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Jun 11, 2015
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For example, if the U wave's amplitude is greater than the T wave's amplitude, then there is likely a serum K+ level of less than 3 mEq.

Additionally, the T wave inverts, and a QU interval appears, due to the T and U waves.

I know K+ efflux out of excitable cells is what maintains the resting membrane potential (negative) and that K+ efflux is what mediates repolarization, but I don't really know how to translate that into the findings on the ECG.

So do you think we should memorize exactly how hypokalemia affects each segment the ECG, or should we just memorize the findings without going that deep?

Thanks, feeling a bit stupid sorry.
 

Jabbed

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For example, if the U wave's amplitude is greater than the T wave's amplitude, then there is likely a serum K+ level of less than 3 mEq.

Additionally, the T wave inverts, and a QU interval appears, due to the T and U waves.

I know K+ efflux out of excitable cells is what maintains the resting membrane potential (negative) and that K+ efflux is what mediates repolarization, but I don't really know how to translate that into the findings on the ECG.

So do you think we should memorize exactly how hypokalemia affects each segment the ECG, or should we just memorize the findings without going that deep?

Thanks, feeling a bit stupid sorry.
The mechanism of U waves is not established. It's thought to be related to repolarization of the His-Purkinje network. So no, you don't really need to know the mechanism.

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