P3.46: A Novel Pump Device for Recycling Gastrointestinal Fistula Losses: Design and Feasibility Study

Abstract

Introduction: Enterocutaneous fistulae are a common cause of intestinal failure, and may necessitate parenteral nutrition (PN) and prolonged hospitalisation. Refeeding of fistula losses back into the distal gut is known to be beneficial, however implementation has been limited because devices are not commonly available, and manual recycling is unpleasant and labour-intensive. We present a novel device designed to enable easy and efficient chyme recycling, and report data from a first-in-human feasibility study. Methods: The novel device comprises a compact centrifugal pump that can be placed inside a standard stoma bag. The pump is connected to an intestinal feeding tube which is inserted into the distal fistula limb. The pump is activated across the stoma bag by magnetic coupling to a custom-designed hand-held driver unit, effecting intermittent bolus refeeding while avoiding contact with the stoma effluent. Five speed settings were included to handle different chyme viscosities. Nutritional, medical, psychological and human-use factors were evaluated in an initial feasibility study. Results: Following benchtop validation, the device was tested in 10 patients (1 drop-out due to unrelated obstruction; median 31d; IQR 22-50d). Indications for inclusion were remediation of high-output fistula / stoma losses (n=7), dependency on PN (n=5), and gut rehabilitation prior to restoration of continuity (n=10). A range of chyme viscosities were successfully recycled with increasing efficiency over the course of the trial, due to iterative device improvements. Patients consumed low residue diets. Once established, chyme recycling was well-tolerated in all patients, using regular boluses of up to 200 ml per episode, performed as many times as needed per day. Patients experienced a variety of benefits including reduced net losses (>65% average volumes), PN cessaton (4/5 patients, including all patients employing the final device iteration), liver function improvement, electrolyte normalisation, and improved quality of life. Of 6 patients with continuity restored at the time of reporting, none experienced post-operative ileus. Conclusions: A novel chyme recycling device was developed and feasibility confirmed in an initial study. The device is easy to use and demonstrates multiple potential benefits including weaning of PN, gut rehabilitation, improved surgical outcomes, and reduced costs of care in these complex patients. A larger efficacy trial is currently planned.