There are plenty of people that have the same thoughts and think the worse. Sad to say they don't attempt a question like this for feer of someone saying "tough sh**". In fact, other forums I have seen said just that to them.
A situation for one of my family members has to take long term medicine in order to survive. 1 hour over their medication date is due and they will be in the hospital for a very very very long time. For them, I advised a plan on how they get their medication. Since they are able to refill their meds 1 week in advance, that leaves them with 1 week of medications in the bug out bag. If they do this everytime they get their medications filled, then eventually they will have enought for 1, 2, 3 years worth of meds. Although medicaitons expire, they rotate the new ones with the old ones now, so they have a fresh supply of medications. That buys them 3 years for society to get their stuff together. I also have members of my family that couldn't walk a mile without getting out of breath, so technically they are immobile as well.
For immobile patients, we would have to weigh out exactly the dangers are in your area. If its a Nuclear plant collapsing, then you would need to have transportation out. If its a flood, then have access to a raft nearby (I know you got plenty of those in your old BOV!) If its a tornado, then have everything in your home/apt, moved to the side so that you can get to the inner hallway. For EMP, terriost attacks, riots, earthquakes etc, then we need to think hard of how you would protect yourself/family for a plan. It all comes down to a plan with things.
Knowing you, with your genius ideas, you'll strap on a lawnmower engine to your wheelchair and make it your new BOVW (Bug out Vehicle Wheelchair!). Videos should be posted in a few days on YT! LOL Hmmm.... do I smell a market fo that?