Surgical stress accelerates postoperative metabolism, while simultaneously compromising gut activity. The dysfunction may be worsened by early feeding. These patients are not expected to fully meet their optimum metabolic requirements using current nutritional regimens. For optimum postoperative enteral nutrition, we must automatically match the patients’ feeding site inflows to their impaired peristaltic outflows. An essential adjunct is virtually complete exclusion of swallowed air. The small diameter post-pyloric duodenum is an efficient site for both aspiration and feeding.

Gastro-intestinal (G-I) motility is impaired ("paralytic ileus") after abdominal surgery. Premature feeding attempts delay recovery by inducing "feeding intolerance," especially abdominal distention that compromises respiration. Controlled studies (e.g., from Sloan-Kettering Memorial Hospital) have lead to recommendations that patients not be fed soon after major abdominal surgery to avoid this complication. We postulate that when total fluid inflow of feedings, digestive secretions, and swallowed air outstrip peristaltic outflow from the feeding site, fluid accumulates. This localized stagnation triggers G-I vagal reflexes that further slow the already sluggish gut, leading to generalized abdominal distention. Similarly, vagal cardiovascular reflexes in susceptible subjects could account for the 1:1,000 incidence of unexplained bowel necrosis reported with enteral feeding. We re-evaluated our data, which supports this postulated mechanism for the induction of "feeding intolerance." We had focused our efforts on postoperative enteral nutrition, with the largest reported series of immediate feeding of at least 100 kcal/hour after major surgery. We found that this complication can be avoided consistently by monitoring inflow versus peristaltic outflow, immediately removing any potential excess from the feeding site. We fed intraduodenally immediately following "open" surgery for 31 colectomy and 160 consecutive cholecystectomy patients. The duodenum was aspirated simultaneously just proximal to the feeding site, efficiently removing all swallowed air and excess feedings. To salvage digestive secretions, the degassed aspirate was re-introduced manually (and later automatically) via a separate feeding channel. Hourly assays were performed for nitrogen balance, serum amino acids, and for the presence of removed feedings in the aspirate. The colectomy patients had X-ray motility studies initiated 5 – 17 hours after surgery. Clinically normal motility and absorption resumed within two hours. Fed BaSO 4 traversed secure anastomoses, to exit in bowel movements within 24–48 hours of colectomy. All patients were in positive protein balance within 2 – 24 hours, with elevated serum amino acids levels and without adverse G-I effects. Limiting inflow to match peristaltic outflow from the feeding site consistently prevented "feeding intolerance." These patients received immediate full enteral nutrition, with the most rapid resolution of postoperative paralytic ileus, to date.

A peristaltic gradient insures that chyme normally removed from the jejunal feeding site continues to be propelled caudad. The trigger for iatrogenic "feeding intolerance" is the inadvertently overwhelming of the jejunum's peristaltic outflow, even momentarily.Even minimum local stasis can stimulate a vagal reflex response. Motility of the sluggish gut further slows, leading to generalized abdominal distention, malaise, immobility, and impaired respiratory mechanics. Vagal vascular reflexes could explain the 1:1000 incidence of bowel necrosis for jejunally fed patients.We developed a clinical regimen that continuously "checks for residual" at the enteral feeding site, monitoring the adequacy of emptying. The jejunal inflow automatically is titrated to match peristaltic outflow if the latter cannot keep up.Intermittent suction aspirates the feeding catheter into a plastic chamber for 30 s. All swallowed air is removed efficiently within the close confines of the jejunal segment, without wasting digestive juices. The degassed aspirate is returned by gravity with the feedings during the second half of the 1-min cycle, unless incipient excess (>= 20 mL) fluid overflows. Only this relatively small volume of potentially excess fluid is discarded, forestalling the local distention.All patients tolerated immediate feeding without discomfort or abdominal distention, including three that had esophageal resection (including vagotomy) for carcinoma. Postoperative full enteral nutrition can be achieved quickly and safely with minimum attention, despite initially marginal gastrointestinal function. (C) 2007 Elsevier Inc. All rights reserved.

"Feeding intolerance" frustrates attempts to enterally nourish patients with marginal gut function. Decompression catheters provide proximal aspiration, removing digestive juices and gas in an effort to minimize this iatrogenic complication. We now add automatic "checking for residual" every minute at the enteral feeding site.Total inflow (feedings plus digestive secretions) is limited to exactly match impaired peristaltic outflow. All air and excess foodstuff are removed by the Moss (R)*tube, with return of the degassed aspirate.The earliest stage of "feeding intolerance" is fluid accumulation at the enteral feeding site. Full feeding now can be initiated safely in the face of impaired GI function. The potential excess can be removed before distention and vagal reflexes further disrupt the sluggish gut.Adding monitoring and refeeding to the current feeding-decompression regimens results in earlier enteral nourishment for patients with critically impaired gut function. Their feeding goals can be safely approached and achieved immediately postoperatively.

A simple and inherently safe Enteral Feeding Monitor/Manager is described for use with standard, single-lumen jejunal tubes. No feedings or GI fluids are removed permanently unless they accumulate adjacent to the catheter. Only such momentary excess is removed promptly, before local distention can develop. The full bore automatically alternates between 30 seconds on suction and 30 seconds for return of the aspirate. Each minute, the removed air bubbles are vented, the residual jejunal volume is measured, and the degassed fluid is returned by gravity.