Incidental Intraoperatively Detected Choledocholithiasis: A General Surgeon's Approach to Management.

Background Up to 15% of patients with cholelithiasis have choledocholithiasis, with almost 10% not detected pre-operatively. Our study aims to quantify the prevalence of incidental choledocholithiasis during routine intra-operative cholangiogram (IOC), identify the best management pathway, and identify reliable pre-operative factors to predict choledocholithiasis. Methods We conducted a single-centre, retrospective cohort study at St John of God Midland Hospital in Western Australia, Perth, on 880 consecutive patients who underwent cholecystectomies performed by 15 surgeons between January 2, 2020, and December 30, 2021.  Results The overall choledocholithiasis rates were 10.6% (93), with 4.0% (35) diagnosed pre-operatively and 6.6% (58) diagnosed during IOC. In all, 50% of incidental choledocholithiasis during IOC were managed with hyoscine butylbromide, with a 55.2% success rate; 22.4% of patients received octreotide, with a 61.5% success rate; and 8.6% of patients underwent trans-cystic bile duct exploration (TCBE) and 8.6% underwent postoperative endoscopic retrograde cholangiopancreatography (ERCP), both with 100% success rates. Choledocholithiasis most commonly presents with gallstone pancreatitis, with a median aspartate aminotransferase (AST) level 7.2 times and alanine transaminase (ALT) level 7.8 times higher than those of patients without choledocholithiasis. Magnetic resonance cholangiopancreatography (MRCP) was the most sensitive in identifying choledocholithiasis with a 66.7% pickup rate. The median common bile duct (CBD) diameter on ultrasound was 8 mm, computerised tomography scans were 11 mm, and MRCP was 9 mm. Conclusion One in 10 cholecystectomies will be complicated with choledocholithiasis, and over half will be incidentally diagnosed during routine IOC. We propose IOC in all cases and hyoscine butylbromide, octreotide, and saline flushes as first-line treatment; if unsuccessful, TCBE is performed. Gallstone pancreatitis, markedly elevated AST/ALT, and imaging showing CBD ≥8 mm may serve as early predictors of choledocholithiasis.