What Is Short Bowel Syndrome?
The definition of short bowel syndrome is controversial; however, patients who are at the greatest nutritional and dehydration risk generally have < 115 cm of residual small intestine in the absence of colon in continuity or < 60 cm of residual small intestine with colon in continuity. Patients with < 100 cm of residual jejunum often have a net secretory response to food and may actually secrete more fluid than they ingest. "Functional" short bowel syndrome may develop in patients with chronic intestinal obstructions, radiation enteritis, refractory sprue, chronic intestinal pseudoobstruction, or congenital villus atrophy (infants) because of poor absorption. Therefore, "intestinal failure" may be better defined by fecal energy loss than by residual bowel length. However, fecal energy loss should be evaluated in the context of energy intake.
The Occurrence of Short Bowel Syndrome
In the absence of registry data, it is impossible to know the precise incidence and prevalence of short bowel syndrome in the United States. On the basis of European data, the incidence of total parenteral nutrition (TPN)-dependent short-bowel patients is estimated between 2 and 3 per million per year, with the prevalence at approximately 4 per year per million. These figures reflect the fact that with appropriate management, many patients with short bowel syndrome can be successfully weaned from TPN with conventional techniques, as described below.
Several different processes -- congenital and acquired -- may result in the development of short bowel syndrome. These include congenital intestinal atresia or conditions for which massive enterectomy may be required, such as gastroschisis, necrotizing enterocolitis, and extensive aganglionosis in infants as well as catastrophic vascular events (mesenteric vein or arterial thrombosis or arterial embolism), midgut volvulus, trauma, or tumor resection in adults. Although less common in the last several years with the use of medications, such as infliximab and surgical strictuloplasties, patients with Crohn's disease who undergo repeated intestinal resections may eventually develop short bowel syndrome as well.
From a medical-management standpoint, patients can be divided into 2 distinct subgroups: those with colon in continuity with their small intestine and those without colon. The colon becomes an important digestive organ in patients with short bowel syndrome -- it absorbs fluid, medium-chain triglycerides, short-chain fatty acids (from carbohydrate salvage, as discussed below), a small amount of amino acids, sodium, and calcium.
© 2004 Medscape
Cite this: The Medical and Surgical Management of Short Bowel Syndrome - Medscape - May 14, 2004.