My parents live in a faraway city and we have an immediate and a long term problem.

Oh what a terrible situation. If your parents can live alone, I would start looking into Assisted Living or Independent Living facilities BEFORE he has the surgery. Hopefully, when your dad has the surgery, he will be placed in a Skilled Nursing home afterwards, but there's no guarantee. It is up to the doctor. Most importantly though - if your parents are already set up or planning for this double hip surgery, his doctor is most likely in NM, which will hinder your dad being placed in a facility up in the DC area as he is licensed in NM - not DC. But if your dad agrees to have a doctor in the DC area do the surgery, he could be placed locally so you can help him and your mom out. But in the meantime, your mom will need a place to stay. If a place is picked out before the surgery, she will have a place to stay. Otherwise, where would she stay? With you? Can she be left alone? Only you really know this information. It's a hard decision any way around. Good luck!!