It's one of the (many) reasons I generally change where I sleep when I'm recovering from surgery. As just one example; Living room, lights full on, drugged to the gills... Means I sleep lighter & without the chemical Smackdown would probably be up for days. But with it? It means when I do come awake, it's fast. And I can see everything. And I don't have a history of coming awake fighting or bolting out of a recliner, whereas I do have a history in bed.
If I'm really being obnoxious, I've belted myself into the car. Seat belts and doors mean I might bang something (ouch), but I'm not going to be attempting to sprint anywhere. A somewhat wiser choice is to unbolt the seat from the car and bring it indoors, or just use climbing rope and a carabiner around my hips in a recliner if no car or the belts are attached to the frame instead of the seat.
Most of the time, though, those things are completely unnecessary. 1. the sudden crushing pain stops me / brings me awake before I've actually gone anywhere & 2. my body is busy recovering from major surgery. Which means PTSD symptoms tend to take a back seat &/or go away entirely, while I'm dealing with an actual physical emergency. It's not a mental/emotional emergency, but the psych all damage being repaired is enough that I'm actually pretty damn normal during the worst of it. It's not until I'm really doing much better that my PTSD stuff swings back. Then I get hit hard, because recovering from major damage is part of my trauma stuff AND I don't have a way to blow off the stress. But the acute time? (Except for coming out of anesthesia, and I have them out me in restraints for that bit.) When it's vital I don't put weight on or move about? I'm usually golden.