How long does paralytic ileus last before it creates problems?

[Nicmulgrew]

On 19 March my husband had his large bowel removed laparoscopically, and was fitted with a permanent ileostomy. After two days of progress (eating, urinating, stoma output that was starting to thicken) he started feeling nauseous, bloated, and in pain. A variety of other events (removal of morphine PCA, removal of IV fluids) led to him not eating or drinking, pain increasing dramatically, and vomiting. He was placed back of IV fluids, PCA morphine, antibiotics, a picc line for TPN, and also had a NG tube inserted on freeflow. A CT scan revealed two large haematomas in his abdominal area as well as ileus. He has now had paralytic ileus for two weeks, is still very distended, and his intestines are full of air. The surgical team keep saying “wait for up to 6 weeks”. My question is, how long can he wait before he ends up with necrosis? Is there anyway to deflate the small bowel? Stoma output is 100-200ml over 24 hours, urine about 1500ml, however input around 2500ml. Thanks.