<P> A medical ventilator (or simply ventilator in context) is a mechanical ventilator, a machine designed to move breathable air into and out of the lungs, to provide breathing for a patient who is physically unable to breathe, or breathing insufficiently . </P> <P> While modern ventilators are computerized machines, patients can be ventilated with a simple, hand - operated bag valve mask . </P>

What does it mean to be on a ventilator in the icu
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