| This probably is not going to answer your question, but... I'm not that old, but I've always been hard to wake. And it seems the older I get, the harder I am to wake. I've always 'heard' that older people need less sleep, and I beg to differ! lol! Now the serious stuff. What kinds of meds (DRUGS!) is your friend being given? And what doses?!! You need to find out and 'research side effects' any drugs your friend is being administered...that could be key to why not waking up. Another thing...I saw a Documentary - TWICE! - on TV (yes, I know, 't.v.') about a lady and (son?) who went vacation to Australia (I think AU...it was a couple years ago I watched it).
So the Mother had an odd thing about 'seeming to be DEAD'! She actually had no pulse, heartrate that showed up on any monitors. So it happened while vacationing in AU - again, and son tried to explain to EVERYONE that this happens - "she's not dead!".
Of course, they always look at him like he's in denial. Come to find out, she DID awake...AGAIN...in the morgue! This was like the third or fourth or??? time this has happened to her! (Spookey, huh?)
Some kind of odd thing with her, but she'd be dead & several days later alive again. OK, I'd take a serious and close look at any/all drugs, strengths of each, times administered, etc. Maybe your friend just doesn't want to wake up until "I'm good & ready"! Talk to your friend...maybe that's what's going on?
(I know, some days I wake up & feel like the whole day is 'bust', so I just want to go back to sleep...)? Not a good healthy thing for someone like me - that's why I usually DO get up. But someone older & in nursing home - who knows? | 
