Sa1042 SINGLE INSTITUTIONAL DIAGNOSTIC ACCURACY OF INTRAOPERATIVE CHOLANGIOGRAMS AND EVALUATION OF PREDICTORS OF POSITIVE FINDINGS.

Abstract

To determine our institutional false-positive (FP) rate of Intraoperative Cholangiograms (IOC) and compare predictors to those listed in current guidelines. IOC is often performed during a cholecystectomy to determine patency of cystic duct and presence of residual stones. Unfortunately, IOCs have reported false-positive rates of up to 60%. It is unclear whether these rates are due to misinterpretation of the cholangiogram (artifacts/air bubbles), passage of the stones prior to endoscopic evaluation, or non-visualization of stones at the time of removal. This high FP rate results in potentially unnecessary endoscopic retrograde cholangiopancreatography (ERCP) and exposing patients to associated risks of pancreatitis, hemorrhage, and perforation. Retrospective review from 2002-2017 identified all IOC (1507 patients) performed at our institution. A total of 245 patients were included in our study, defined as having a positive IOC. In all the included patients, we collected demographics, indication for cholecystectomy, IOC findings, blood tests before and after cholecystectomy, ERCP/Endoscopic ultrasound (EUS) results (Table 1), and number of days between cholecystectomy and endoscopic evaluation. Analysis using SPSS was performed to assess for statistically significant associations between potential risk factors and a positive IOC. The data from 245 patients was analyzed using SPSS (version 24). 184 patients (75.2%) were female and 61 (24.8%) were male. The mean age was 47.9 years (SD 20.49 years). 241 patients (98.4%) had either non-passage of contrast into the duodenum, filling defects on IOC, or both. Stones were present in 145 patients (59.2%) at the time of ERCP, giving a FP rate of 40.8%. The mean length of time between IOC and ERCP was 1.75 days (range 1-9 days). Univariate analysis revealed that patients who had an elevated direct bilirubin level prior to cholecystectomy and an elevated total and direct bilirubin level after cholecystectomy, were more likely to have a stone on ERCP (p < 0.021). However, these factors were not significant predictors on multivariate analysis. No additional factors, including transaminases, pancreatic enzymes, or WBC were found to be predictors of stone on ERCP (Table 2). 5 patients (0.56%) who had a stone on EUS, did not have a stone on ERCP. High FP rates of IOC render its use controversial. Bilirubin was the only predictor of stone on ERCP. This reinforces the need to evaluate the role of additional tests such as EUS, with prospective studies to help determine which patients can avoid ERCP. Further validation of currently published guidelines should also be performed to improve results.Tabled 1Endoscopic Findings.PROCEDURE:Imaging only, n (%)20 (8.1)EUS only, n (%)3 (1.2)ERCP only, n (%)213 (87)EUS followed by ERCP, n (%)9 (3.7)EUS FINDINGS (n=12):No stones, n (%)3 (25)Stone(s), n (%)9 (75)CBD dilated on EUS , n (%)7 (58)ERCP FINDINGS (n=222):No stones, n (%)100 (45)Stone(s), n (%)145 (65)CBD dilated on ERCP , n (%)94 (42) Open table in a new tab Tabled 1Potential Predictors of stone on ERCP.N (Patients with stone on ERCP)MeanStd. DeviationP ValuePre-CCY T.Bili1452.2662.91780.484Pre-CCY D.Bili1451.1921.95780.022Pre-CCY AST145236.45263.4510.46Pre-CCY ALT145295.4303.6540.161Pre-CCY Alk Phosph145174.88118.3650.63Pre-CCY WBC1459.59493.96810.626Post-CCY T.Bili1452.313.15590.018Post-CCY D.Bili1451.2482.07830.02Post-CCY AST145137.58116.3920.183Post-CCY ALT145230.8195.0140.089Post-CCY Alk Phosph145164.0691.0070.63Post-CCY WBC1459.46343.230380.764 Open table in a new tab