Identification of Clinical Outcome Measures for Recovery of Gastrointestinal Motility in Postoperative Ileus

Objective: To identify clinical hallmarks associated with recovery of gastrointestinal transit. Background: Impaired gastrointestinal transit or postoperative ileus largely determines clinical recovery after abdominal surgery. However, validated clinical hallmarks of gastrointestinal recovery to evaluate new treatments and readiness for discharge from the hospital are lacking. Methods: Gastric emptying and colonic transit were scintigraphically assessed from postoperative day 1 to 3 in 84 patients requiring elective colonic surgery and were compared with clinical parameters. The clinical hallmark that best reflected recovery of gastrointestinal transit was validated using data from a multicenter trial of 320 segmental colectomy patients. Results: Seven of 84 patients developed a major complication with paralytic ileus characterized by total inhibition of gastrointestinal motility and were excluded from further analysis. In the remaining patients, recovery of colonic transit (defined as geometric center of radioactivity 2 on day 3), but not gastric emptying, was significantly correlated with clinical recovery ( = -0.59, P <0.001). Conversely, the combined outcome measure of tolerance of solid food and having had defecation (SF + D) (area under the curve = 0.9, SE = 0.04, 95% CI = 0.79-0.95, P <0.001), but not time to first flatus, best indicated recovery of gastrointestinal transit with a positive predictive value of 93% (95% CI = 78-99). Also in the main clinical trial, multiple regression analysis revealed that SF + D best predicted the duration of hospital stay. Conclusions: Our data indicate that the time to SF + D best reflects recovery of gastrointestinal transit and therefore should be considered as primary outcome measure in future clinical trials on postoperative ileus. (Netherlands National Trial Register, number NTR1884 and NTR222)