ERCP-to-Cholecystectomy Interval and Operative Time: A Retrospective UK Cohort Study

Background Laparoscopic cholecystectomy (LC) is recommended after endoscopic retrograde cholangiopancreatography (ERCP) and duct clearance to reduce recurrent biliary events, but the relationship between treatment interval and operative complexity remains uncertain. We assessed the association between the ERCP-to-LC interval and operative time in routine NHS practice. Methods This single-centre retrospective cohort included adults undergoing ERCP followed by LC at Wirral University Teaching Hospital NHS Foundation Trust from January 2023 to September 2024. Patients were grouped by ERCP-to-LC interval (≤ 7, 8–14, 15–42 and ≥ 43 days). The primary outcome was operative time, compared using the Kruskal–Wallis test. An exploratory log-linear model with HC3-robust standard errors adjusted for age, sex, body mass index and surgical specialty. Secondary outcomes included postoperative length of stay, subtotal cholecystectomy, conversion to open surgery and 30-day readmission. Results Sixty-six patients were included, with operative-time data available for 65. The four timing groups contained 24, 7, 14 and 21 patients. Median operative times were 76.5, 99.0, 85.5 and 76.5 minutes, respectively (Kruskal–Wallis p = 0.485; ε²=0.000). Relative to ≤ 7 days, adjusted differences were + 23.1% (95% CI − 19.7% to 88.6%), + 26.9% (− 9.1% to 77.2%) and − 8.3% (− 28.1% to 16.9%); the joint timing-group p value was 0.136. Conversion to open surgery occurred in 1/66 patients (1.5%), and 30-day readmission in 2/66 (3.0%). Emergency general surgery (EGS) patients underwent LC sooner than upper gastrointestinal surgery (UGI) patients (median 14.5 versus 28.5 days; p = 0.045), while operative times were similar. Conclusions Although the 8–14-day group had the highest observed median operative time, neither the unadjusted nor adjusted analysis established an independent timing association. The estimates were imprecise and do not identify a discrete post-ERCP danger zone or provide evidence that delaying LC beyond six weeks reduces operative time.