In the 24 patients with <100 cm small bowel (mean, 50 cm) remaining, the amount of energy delivered parenterally was reduced by half if 50% or more of the colon was functional. Therefore, preservation of the colon is of key importance during surgery, and all available bowel should be placed back into continuity as soon as clinically safe in order to maxi­mize absorptive potential.

case, nutrient, fl uid, and electrolyte balance can be severely impaired. A similar situation may be seen if the anastomosis from the fi rst or second confi guration leaks and develops into an enterocutaneous fi stula.

After extensive small bowel resection, adaptation of the remaining intestine begins quickly and proceeds for up to 2 years, with the main response occurring within a few months of resection. The adaptive process can be divided into three clinical stages. The fi rst stage occurs during the immediate postoperative period when the loss of GI secre­tions can be extraordinarily high. During this stage, fl uid, electrolytes, and nutrients are provided parenterally until the patient is stabilized. During the second stage, there is a gradual transition from PN to enteral nutrition (EN) or oral feedings as adaptation occurs. In the third stage, there is the realization of complete independence from PN in patients with suffi cient intestinal absorptive capacity and adequate enteral or oral intake. In patients with high volume GI losses who are scheduled to undergo bowel reconnection within 3 months of their initial surgery, PN or intravenous fl uids (IVF) should be given without regard to adaptation because this process takes at least a few months for most individuals.

of IF. In general, patients with <100 cm jejunum-ileum prox­imal to the fi stula or enterostomy will likely require PN sup­port until bowel reconnection [ 12 ] . Patients with 100–150 cm of functional jejunum-ileum may be supported with diet and a combination of IVF and/or EN until reconnection. Those with more than 150 cm of jejunum-ileum are often able to maintain adequate nutrition and hydration through oral mea­sures alone after the initial surgical trauma and/or infectious process subsides. It is important to emphasize that therapy is individualized, outcomes are closely monitored, and inter­ventions are routinely modifi ed based on patient progress.

It is important to note that citrulline levels are low in the immediate post-extensive bowel resection phase, and levels increase over time with adaptation. We recently evaluated plasma citrulline levels of 30 PN-dependent patients with SBS in the post-adaptation phase and were able to confi rm the ability of post-absorptive plasma citrulline to estimate small bowel length [ 18 ] . A citrulline cutoff of 26 m mol/L had a sensitivity of 80% and a specifi city of 75.6% in predicting the need for long-term PN in our SBS population.

absorption was ³ 84% of the basal metabolic rate as calcu- lated by the Harris Benedict equation [ able testing includes a 72-h stool collection for fecal fat and the d -xylose absorption test. When malabsorption is severe, these tests are generally not necessary. They are occasionally helpful when one needs to determine if transition from par­enteral therapy to an oral diet is feasible or when one consid­ers placement of an enteral feeding device.

the remaining bowel. In general, patients with malabsorption sustained without PN should receive up to three divided doses of the recommended daily allowance (RDA) for vitamins and trace minerals in tablet, powder, chewable, or liquid form.

Patients with <100 cm jejunum-ileum in an end enteros­tomy or ECF, <65 cm jejunum anastomosed to colon or <30 cm jejunum-ileum anastomosed to colon will likely require long-term PN or IVF to maintain nutrient and fl uid balance [ 33 ] . Those with preexisting malnutrition will require PN for at least 7–10 days following an extensive small bowel resection regardless of remaining anatomy and bowel lengths [ 31 ] . Thereafter, all attempts should be made to transition the patient onto an oral or enteral diet when clinically feasible.

In a carefully conducted nutrient balance study, Jeppesen et al. found that SBS patients who absorbed less than half of their daily intake were able to avoid the need for home PN through hyperphagia [ 20 ] . However, hyperphagia may lead to exceptionally high outputs in patients with preexisting fecal losses above 4 L/day. In these cases, oral intake should be limited to several extremely small meals per day (i.e., one serving starch per meal), and fl uid intake may need to be restricted to no more than 1 L of ORS sipped daily. This type of restriction is imposed in order to reduce losses to the point where IV replacement can occur safely in the home setting. The IV solution is slowly weaned off as small portions of appropriate foods and fl uids are reintroduced with the goal of maintaining urine output above 800 mL/day [ 20 ] .

All patients with large fecal losses will generally benefi t from a diet divided into several small meals per day and lim­ited in simple sugars in order to minimize the osmolar load to the GI tract. For SBS patients with colon, a diet high in complex carbohydrates (50–60% of total calories) and low in fat (20–30% of total calories) with isotonic or hypotonic fl u­ids sipped between meals is recommended. In SBS patients without colon, a moderate carbohydrate (40–50% of total calories), moderate fat (30–40% of total calories), and calori­cally dense diet is most optimal (see Table 8.5 ) [ 35 ] .

feeding tube by overnight continuous drip or by intermittent bolus as a replacement for the traditional water fl ush. Nauth et al. described three SBS patients who were weaned off of PN by optimizing enteral fl uid absorption through the use of nocturnal enteral rehydration [ 41 ] .

resins such as cholestyramine to reduce the irritation of bile acid contact with the colonic mucosa. Use of octreotide or clonidine to inhibit GI secretions and delay small bowel tran­sit is best reserved for patients with large volume secretory diarrhea refractory to standard antidiarrheal and antisecre­tory therapy [ 45, 46 ] .

was inserted by interventional radiology into the ECF, and semi-elemental feedings were gradually advanced to goal with subsequent discontinuation of PN. Liver function tests improved and nutritional parameters such as visceral pro­teins and weight increased during fi stuloclysis to allow for successful surgical repair of ECF.

Octreotide may be administered subcutaneously (100 mcg every 8 h), intramuscularly (10–30 mg monthly), or via the PN solution. Subcutaneous octreotide and PN begun within 48 h of fi stula onset were able to achieve a 94% mean reduc­tion in ECF output and a 78% ECF closure rate within the fi rst month of administration in a review of 40 patients with postoperative ECFs [ 60 ] . Although subcutaneous octreotide injection was shown to induce a 50% mean reduction in ECF output within 24 h of administration, a signifi cant effect on spontaneous ECF closure was not observed in a retrospective analysis of 21 PN-dependent patients [ ducted a multicenter, prospective, randomized, double-blind, placebo-controlled trial to compare administration of PN plus subcutaneous octreotide within 8 days of fi stula onset with PN alone [ while 17 patients were studied in the control arm. The mean reduction in fi stula output over the fi rst 3 days of treatment and the frequency of fi stula closure at 20 days were no differ­ent between the two study groups. Overall, these results sug­gest that the main effect of octreotide is to reduce the volume of fl uid and quantity of electrolytes lost through an ECF.