Can someone with sleep apnea w/ oxygenation drops become delirious if she hasn't been using her cpap? Mom in hospital w/ severe confusion.

Yes Most Definately. The scientific literature is repleat with examples of delerium contributed to sleep apnea. It occurs most often in older adults. Whenever a patient presents to a hospital with new onset delerium and has a history of sleep apnea one should consider ncpap. Delerium is defined as a disturbance in consiousness accompanied by an acute change in cognition not accounted for by dementia.
Yes, but. The delirium should pass once she's awake. If the delirium continues long after wakefulness another explanation needs to be found. Her age, health, habits and diet may play a role as well. This seems to be a neuropathologic event or intoxication.
Yes. When oxygenation levels drop below 90% consistantly, a whole host of symptoms and problems can ensue with severe confusion being one of them.