Can hospital patients sleep with oxygen masks on overnight?

The oxygen masks deliver pure oxygen, right? Wouldn't it be bad for someone to breath through an oxygen mask all night? Or are there cases where that's necessary?Can hospital patients sleep with oxygen masks on overnight?
yes and they have another one fits in your nose, that way you can speakCan hospital patients sleep with oxygen masks on overnight?
Generally speaking overnight breathing would use the nostril hose you are not breathing 100% oxygen but just a lot higher mix of air/oxygen
Yes they can. This is not harmful. It helps you breathe better.

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