Short Bowel Syndrome

Abstract

Short bowel syndrome (SBS) occurs following surgical resection of the small intestine due to illnesses such as Crohn’s disease, ischemia, trauma, volvulus, and malignancy. SBS is anatomically defined by a postoperative remnant intestinal length of <200 cm. Intestinal failure and chronic parenteral nutrition dependence generally occur in patients with <100 cm of small bowel ending in a jejunostomy, <35 cm of jejunum with a jejunoileal anastomosis, or <50 cm with a jejuno-colonic anastomosis. SBS results in reduced nutrient, fluid, and electrolyte absorption, leading to dehydration, weight loss, diarrhea, and malnutrition including macro and micronutrient and vitamin deficiencies. The diagnosis is made by imaging studies that demonstrate reduced small bowel length, and/or by clinical criteria that indicate diminished small bowel absorptive function and dysmotility. The treatment of SBS includes both medical and dietary interventions. Medications are prescribed to control diarrhea by increasing bowel transit time, reducing intestinal secretion, and enhancing mucosal growth. Specific dietary and nutritional management, tailored to the patient’s postsurgical intestinal anatomy, is required to reduce diarrhea, enhance calorie absorption, and avoid vitamin and micronutrient depletion. Parenteral nutrition provides calorie as well as fluid and electrolyte support, and is closely monitored in patients with intestinal failure. Fluid and electrolytes may also be repleted by oral rehydration solutions as well as additional intravenous fluids. Monitoring nutritional status on a regular basis is required to avoid osteoporosis, neuromuscular complications, and other end organ damage. Surgical options include intestinal lengthening procedures and finally intestinal/multi organ transplantation for patients with intestinal failure and parenteral nutrition dependence who have frequent central line infections, loss of intravenous access, or liver failure. The management of SBS with intestinal failure remains challenging, with few therapeutic options and substantial morbidity and mortality.