Sa1574 - Postoperative Ileus is a Risk Factor for Anastomotic Leakage

using the scintigraphy results at 2-hours.Results: 900 patients were reviewed and 703 (78%) (mean age 46.5, range 13-86, 74% females) met study criteria.166 patients (24%) demonstrated GP at 4-hours (42% mild, 18% moderate and 40% severe).ROC is shown in figure.The single 2-hour cutoff value that maximized both sensitivity and specificity was determined to be 44% retention, with 82.0%(sensitivity), 82.5%(specificity), 59.1%(PPV) and 93.7%(NPV) to diagnose GP (>10% retention at 4-hours).Optimal cutoff to exclude GP was #28% retention at 2-hours (95% sensitivity, 97% NPV).Optimal cutoff to diagnose GP was $62% retention at 2-hours (95% specificity, 76% PPV).Optimal cutoff to diagnose severe GP was $69% retention at 2-hours (95% specificity, 83% PPV), see table.We propose a 4-hr gastric scintigraphy protocol of stopping the test early if 2-hour retention is #28% or $69% and continuing the test to 4-hours if 2-hour retention is 29-68%.This protocol will have a 95% sensitivity to exclude GP and a 95% specificity to diagnose severe GP.If we implement this protocol with our 703 patients, 332 (47%) can stop the test at 2-hours, and 371 (53%) will need to continue the test to 4-hours.Conclusions: An adaptive 4-hr solid gastric scintigraphy protocol is feasible using the 2-hour result.However, positive predictive value of the 2-hour result may not be adequate to diagnose severe GP, such as patients with propensity for bezoars.Optimal 2-hour cutoff values to diagnose mild, moderate and severely delayed gastric emptying at 4-hours