The age of your husband is very important. Enlarged prostate
may come after the age of 50 and never exhibits all of a sudden. it is a slow process which could be suspected either by urgency of urination or delayed urination.
USG of abdomen Pre operatively will reveal the degree of enlarged prostate. Moreover as per your statement nobody has told that your husband is having EP now. It seems that your husband has developed paralytic ileus
post operatively which is more common in intra abdominal surgery
There are medical treatment for paralytic ileus. somtimes he may be put on IV fluids avoiding per oral.
But the treatment he is getting now and the complaints you say go in favor of EP.
Consult your doctor for proper advise and plan further management.