Massive Portal Venous Gas Related to Small Bowel Ischemia

Abstract

Purpose: Aim: To describe a case of massive portal venous gas (PVG) related to small bowel ischemia and highlight the radiographic findings related to this clinical entity. Case Report: A morbidly obese and diabetic 76 yo female presented with a 3 day history of constipation, mid abdominal pain and vomiting. Surgical history was significant for prior hysterectomy with partial colon resection, temporary colostomy placement and incidental appendectomy in the remote past (related to a migrated intrauterine device). Upon admission, CT of the abdomen/pelvis revealed dilated loops of small bowel and a ventral hernia which contained a loop of transverse colon. The latter had been seen on a CT scan performed 2 years previously. The primary care team believed symptoms were related to a fecal impaction, and the patient was treated with manual fecal disimpaction, tap water enemas and intravenous hydration. 72 hours following hospital admission, abdominal pain worsened and vomiting recurred. An obstruction series revealed dilated small intestine and stomach, and the radiologist interpreted it as also demonstrating either pneumobilia or portal venous gas (PVG). 12 hours later, GI consultation was sought after dark red-colored hematemesis occurred. At this point the patient became hypotensive and required vigorous intravascular fluid expansion and a vasopressor to maintain relative hypotension. Review of the recently performed plain abdominal radiograph suggested that massive PVG was undoubtedly present (branching air lucencies were noted to extend to the periphery of the liver). Intestinal ischemia was suspected, broad-spectrum antibiotics were started and immediate laparotomy was orchestrated (within 60 minutes of GI consultation). At laparotomy, the entire small bowel was severely ischemic-appearing, but it was macroscopically judged to be viable, after a pelvic adhesive band was lysed, which appeared to be the cause of intestinal obstruction and secondary ischemia (the ventral hernia which contained a loop of transverse colon was incidental). On the following day, hypotension persisted and both respiratory and renal failure ensued. Repeat laparotomy was declined by the patient and her family. The patient expired later that day. Conclusions: (1) Small intestinal obstruction should not be attributed to rectal fecal impaction, (2) PVG produces branching air lucencies which extend to the periphery of the liver, (3) In the setting of acute abdominal pain and hypotension, the finding of PVG suggests an intra-abdominal catastrophe which mandates emergent laparotomy.