Acute intestinal failure
Complete necrosis and gangrene of the midgut resulting from cessation of blood flow in the superior mesenteric artery. It is predominantly a disease of the elderly.
There may be a preceding history of non-specific symptoms (variable abdominal pain, diarrhoea, vomiting and weight loss). Signs of acute intestinal failure include abdominal tenderness, guarding, loss of bowel sounds and rigidity, due to perforation.
Calcification within the abdominal aorta may be evident on abdominal X-ray. Gas filled, thickened, dilated bowel loops and free gas within the peritoneal cavity due to perforation may also be seen. Angiography or spiral CT can identify the vascular occlusion.
Following adequate resuscitation laparotomy and resection (which may be massive) are required. Removal of the vascular occlusion may be possible (e.g. embolectomy). A second look laparotomy can be performed 24 hours later to reexamine any segment of bowel the viability of which was questionable.
The overall prognosis is poor with 70–90% mortality. If the patient survives they have considerable malabsorption problems.