My 88 year old mother has an enlarged hiatus hernia.

She has just spent 12 days in hospital..because of constantly retching belching feeling sick and unable to eat properly for almost 4 months prior..obviously because of her age..surgery isn't possible..but since coming home..I have been able to get her to eat small amounts of finely chopped cooked vegetables mash soup poached eggs etc..but the belching afterwards for hours is horrendous..she's literally exhausted and moaning and groaning..and talking to herself..surely there must be some way of addressing this..the hospital didn't give her any medication for it and for the most part...just ignored her discomfort..any help on this subject would be appreciated