Chronic hard belly suddenly soft

Hello!

I’m a CNA and have just a general question in regards to one of my residents- mostly just curiosity.

Res, for as long as i’ve known him (3 years) has always had a chronically hard and round belly. He is immobile, non verbal ect. Nothing noted to really give reasons for the hard belly- but it is not uncommon in individuals who are in the same state as him, especially men.

He’s declined further, and has pretty much stopped eating the last two days. However, he has gone through periods like this before and even with weight loss during these periods in the past he has never lost the hard belly. He will typically have a few days with very little intake, and then a few days of normal eating so it’s not super uncommon.

Yesterday, it was normal. I didn’t notice anything different- but today his belly is no longer hard and his ribs seem more prominent. It shocked me when I was doing morning care and seems like a sudden change from yesterday and not like he would all of a sudden lose weight like that over 24 hours.

Could this be related to decreased fluid intake? Or perhaps a sign that he is going to pass soon or something? Just seems so weird that it was such a sudden change.