When Irrigation Flows the Wrong Way: Intraoperative Regurgitation Through an Enterovesical Fistula

Enterovesical fistulas complicate inflammatory bowel disease, particularly after restorative proctocolectomy with ileal pouch-anal anastomosis, creating pathways that may complicate endoscopic urological procedures performed under continuous irrigation. A 33-year-old man (61 kg; body mass index 18.8 kg/m²) with unclassified pancolitis (no histological features of Crohn disease in the colectomy specimen) had undergone restorative proctocolectomy with an ileal J-pouch, defunctioning loop ileostomy and ileal pouch-anal anastomosis, with repeated failed interventions for a chronic enterovesical fistula. He underwent elective laser cystolithotripsy and suprapubic catheter exchange. After induction with fentanyl, lidocaine, propofol and rocuronium, the airway was managed with a size 4 i-gel (Intersurgical Ltd, Wokingham, UK), without an orogastric tube in its gastric channel, in the lithotomy position, with gravity-fed 0.9% saline irrigation. One hour and 23 minutes after the start of surgery, clear fluid appeared at the oropharynx. The oropharynx was suctioned, the trachea was intubated, and a nasogastric tube was placed; a second episode followed two minutes later. Irrigation was stopped. The ileostomy appliance, empty at induction, was completely distended with clear fluid, and irrigation return through the cystostomy was markedly reduced. Core temperature on admission to the intermediate care unit was 33.0 °C. Ventilatory parameters, auscultation, arterial blood gas analysis, and chest radiography showed no evidence of aspiration. He was discharged on postoperative day 7. We propose that the regurgitated fluid was predominantly irrigation fluid that had migrated retrogradely through the fistula into the ileal pouch and small bowel. To our knowledge, this mechanism has not been described previously. Fistulous urinary-gastrointestinal anatomy warrants treatment as an aspiration risk factor in its own right, with gastric-channel drainage whenever a supraglottic device is used, and deliberate monitoring of irrigation input, drainage return, stomal output, and core temperature.