I would suggest a couple of things. First, in case you haven't, go with him to an appointment with his doctor. There are many things that affect recovery time. For example, does he have Type 2 diabetes? That would double healing time. Second, how much exercise can he stand? The more activity, the shorter the healing time; on the other hand, you don't want him to blow out a valve.
Second, I double the **82** comment from tdotter. Older people **82** less and less, but the more **82**, the faster the healing.
Also, not so pleasant but important: Are you the person who would make health care decisions if he couldn't? My Dad and I had that talk several times and I had a list by the the time I needed to make decisions: Hydration, yes; dialysis, no. That sort of thing.