One thing I have found is that there is a real need for patient advocates. Whether it is understanding billing, sorting out the myriad of meds or just helping the patient through the minefield that is healthcare. Is that something your DH might be interested in researching? For example, my mother's husband is on at least 15 different meds. Turns out he is being poisoned by the interactions of some of them. A patient advocate can review things like that to prevent this from happening. Even something as simple as helping someone to understand the hospital/insurance billing. It is a foreign language to the average person.
Just a thought.
Of all the paths you take in life, make sure a few of them are dirt.