Comment on Small Bowel Necrosis

Nineteen malnourished chronic peritoneal dialysis patients who were ingesting a low protein intake underwent metabolic balance studies to test whether a dialysate that contained amino acids would improve their protein nutrition. Patients lived in the hospital for 35 days while they ate a constant diet and underwent their usual regimen of continuous ambulatory peritoneal dialysis (CAPD). The first 15 days served as a Baseline Phase. For the last 20 days, the usual dialysate was substituted with a dialysate of essentially the same composition except that it contained 1.1% essential and nonessential amino acids and no glucose. Patients received one or two dialysate exchanges with amino acids each day depending on the amount necessary to bring the individual’s dietary protein plus dialysate amino acid intake to 1.1 to 1.3 g/kg body weight/day. During Baseline, patients were in neutral nitrogen balance; net protein anabolism was positive, as determined from 15 N-glycine studies. After commencing intraperitoneal amino acid therapy, nitrogen balance became significantly positive, there was a significant increase in net protein anabolism, the fasting morning plasma amino acid pattern became more normal, and serum total protein and transferrin concentrations rose. Patients generally tolerated the treatment well, although some patients developed mild metabolic acidemia. These findings indicate that a dialysate containing amino acids may improve protein malnutrition in CAPD patients ingesting low protein intakes. (Kidney Int 1995;47:1148-57) COMMENT: This strong piece of research overcomes the limitations of previous studies of the effects of amino acidbased dialysate for CAPD patients by (1) selecting a population of patients who clearly were malnourished and (2) following them metabolically for an extended period. The definition of malnutrition included evidence for muscle wasting, body weight < 90% desirable or serum albumin < normal, and inadequate dietary protein intake. The population thus selected should represent patients with existing malnutrition and no expectation of correction of protein deficits by dietary means alone. In fact, the mean body weight relative to desirable body weight was 91 +/13%, and 11 of the 19 patients were < 86% of desirable body weight. The mean albumin concentration was 3.6 g/dL with a range of 2.3 to 3.9. All but one of the 19 patients had multiple objective signs of malnutrition. The patients received a stable dietary intake and their usual CAPD regimen for 15 days, and then followed with the amino acid treatment regimen. It is not clear that either the patients or the investigators were blinded to the treatment given. Unfortunately, all patients received Baseline Phase treatment first followed by Treatment Phase, leaving the results open to confounding by time-treatment interactions. The small sample size also leaves the possibility of a Type II statistical error in some results, and no power statistics are calculated. The increases in transport proteins are not unexpected. Albumin, with its 21-day half-life, did not change significantly over the treatment period, while transferrin, with its 14-day half-life, did. The nitrogen balance studies covered 9day periods at the end of each phase, and allowed 6 to 11 days for adjustment to the level of protein intake before nitrogen balance began. The mean nitrogen balance during the Baseline Phase was +0.5 g/day and + 1.71 g/day in the Treatment Phase, a significant difference. Nitrogen intake increased from 8.32 g/day duringBaseline to 13 g/day during Treatment as a result of the l.l% amino acid dialysate. Sixteen of the 19 subjects underwent protein turnover studies, which showed no difference in protein degradation but a significant increase in net anabolism. In general, the amino acid solutions were well-tolerated by patients. One undesirable side effect was a mild metabolic acidosis (decrease in the serum carbon dioxide concentration from 25 to 21). Arterial blood gas measurements on seven patients, however, documented normal pH. This study represents an important treatment option for clinically stable but malnourished end-stage renal disease patients with CAPD as their dialysis treatment modality. While the increase in protein intake may appear limited (mean of 29 g/day) relative to usual TPN levels of intake, malnourished subjects responded favorably over a timeframe of 20 days. Charlene Compher, MS, RD, CNSD Small bowel necrosis associated with postoperative jejunal tube feeding CD SCHUNN, JM DALY University of Pennsylvania School of Medicine, Philadelphia ABSTRACT: Background: Postoperative enteral nutrition using jejunal tube feeding is widely practiced and usually well tolerated. Functional intestinal complaints occur frequently but generally respond to alteration of the infusion rate or tube feeding formula. Occasionally, however, nonspecific signs of intestinal disturbance progress to a syndrome of abdominal distention, hypotension, and hypovolemic shock resulting in extensive small bowel necrosis. Study design: During a six-year period, four patients have been identified retrospectively who had this complication among 1,359 patients receiving jejunal tube feeding. Their clinical course was evaluated critically and compared with 11 cases described in the literature. Results: Small bowel necrosis is a rare but highly morbid complication associated with postoperative jejunal tube feeding. Of 14 patients who had small bowel necrosis develop, 12 succumbed to Background: Postoperative enteral nutrition using jejunal tube feeding is widely practiced and usually well tolerated. Functional intestinal complaints occur frequently but generally respond to alteration of the infusion rate or tube feeding formula. Occasionally, however, nonspecific signs of intestinal disturbance progress to a syndrome of abdominal distention, hypotension, and hypovolemic shock resulting in extensive small bowel necrosis. Study design: During a six-year period, four patients have been identified retrospectively who had this complication among 1,359 patients receiving jejunal tube feeding. Their clinical course was evaluated critically and compared with 11 cases described in the literature. Results: Small bowel necrosis is a rare but highly morbid complication associated with postoperative jejunal tube feeding. Of 14 patients who had small bowel necrosis develop, 12 succumbed to at American Society for Parenteral and Enteral Nutrition (A.S.P.E.N.) on July 8, 2016 ncp.sagepub.com Downloaded from