This is sumbline for so many reasons
1.This is a superb waste of ink.
2. At what point of (un)dress did said patient realise this was a pillow case? (over the head leading to an impromptu execution reenactment, or the ‘stepping into’ school of dressing leading to gleeful nostalgia about your primary school sports day sack race victory).
3. If said patient had enough energy to get this incensed about something this trivial (and frankly hilarious) they are not ill enough to be in hospital.
4. Wouldn’t a better way to deal with this be:
"Oh hi ward sister, I know you are in the middle of a 16 hour shift, and I know you have bed pans to change and tubes to stick in orifices, but through your exhaustion induced haze you appear to have picked me up a pillow case instead of a gown.  I had a little laugh about it, imagining all the ways I could wear the pillowcase, but if you could grab me a gown at some point that would be great".
Original Sorce: Quite possibly