In an adult undergoing cholecystectomy with right upper quadrant (RUQ) pain, jaundice, and abnormal liver function tests (LFTs) suggestive of choledocholithiasis, what is the safest and most effective intra‑operative strategy, including the role of intra‑operative ultrasound (IOUS)?

Intraoperative Ultrasound for Choledocholithiasis During Cholecystectomy

In adults undergoing cholecystectomy with suspected choledocholithiasis (RUQ pain, jaundice, abnormal LFTs), intraoperative ultrasound (IOUS) is a highly accurate alternative to intraoperative cholangiography (IOC) for detecting common bile duct stones, with comparable sensitivity (87%) and superior specificity (100%), but routine use is not recommended—reserve it for selective cases based on preoperative risk stratification.

Risk Stratification Before Surgery

Stratify patients preoperatively using the modified SAGE-AGES criteria to determine the need for intraoperative imaging: 1

High-Risk Patients (Proceed Directly to Intervention)

• Very strong predictors: CBD stone visible on ultrasound OR total bilirubin >4 mg/dL 1
• Strong predictors: CBD diameter >6 mm (with gallbladder in situ) OR bilirubin 1.8-4 mg/dL 1
• Management: These patients should undergo preoperative ERCP, or have intraoperative cholangiography/laparoscopic ultrasound available, depending on local expertise 1

Moderate-Risk Patients (Require Additional Testing)

• Abnormal liver biochemical tests other than bilirubin, age >55 years, or clinical gallstone pancreatitis 1
• Preoperative options: MRCP (sensitivity 93%, specificity 96%) or endoscopic ultrasound (sensitivity 95%, specificity 97%) 1
• Intraoperative options: IOUS or IOC both demonstrate pooled sensitivity of 87% and specificity of 99-100% 1

Low-Risk Patients (No Routine Imaging Needed)

• No predictors present—proceed directly to cholecystectomy without routine intraoperative imaging 1

Role of Intraoperative Ultrasound

IOUS serves as an effective tool for selective use during cholecystectomy when:

Primary Indications for IOUS

• Inability to achieve critical view of safety during dissection, requiring anatomical clarification 1
• Suspected bile duct injury detected intraoperatively—IOUS can evaluate vascular injuries associated with BDI and should be preferred to further hilar dissection to avoid additional damage 1
• Moderate preoperative risk for choledocholithiasis when preoperative MRCP/EUS was not performed 1

Performance Characteristics

• Meta-analysis demonstrates IOUS has pooled sensitivity of 0.87 (95% CI 0.80-0.92) and specificity of 1.00 (95% CI 0.99-1.00) for detecting CBD stones 1
• IOC shows comparable sensitivity of 0.87 (95% CI 0.77-0.93) but slightly lower specificity of 0.99 (95% CI 0.98-0.99) 1
• No significant difference in diagnostic accuracy between IOUS and IOC for identifying choledocholithiasis 1

Why Routine Use Is Not Recommended

Despite high accuracy, routine intraoperative imaging (including IOUS) does not reduce bile duct injury rates:

• A survey of 3,411 surgeons with average 16.1 years of experience found that routine or selective use of IOC, ICG cholangiography, or IOUS during difficult cholecystectomies was not significantly associated with lower risk of bile duct injuries 1
• The critical view of safety technique remains the primary method for preventing bile duct injury, not adjunctive imaging 1
• Routine imaging commits substantial time and resources without proven benefit in reducing major complications 2

Practical Algorithm for Intraoperative Strategy

Step 1: Preoperative Assessment

• Obtain liver function tests, bilirubin, and transabdominal ultrasound (96% accuracy for gallstones) 1
• Apply SAGE-AGES risk stratification 1

Step 2: High-Risk Patients

• If CBD stone visible on ultrasound: Proceed directly to preoperative ERCP for stone clearance 1
• If bilirubin >4 mg/dL without visible stone: Consider preoperative MRCP, then ERCP if confirmed 1

Step 3: Moderate-Risk Patients

• Preferred approach: Preoperative MRCP or EUS to confirm/exclude CBD stones 1
• Alternative approach: Proceed to surgery with plan for IOUS or IOC if local expertise available 1
• If stones confirmed intraoperatively: Laparoscopic CBD exploration by experienced surgeon (94% successful clearance rate) or postoperative ERCP 2

Step 4: Low-Risk Patients

• Proceed directly to cholecystectomy without routine intraoperative imaging 1
• Only 0.9% will present postoperatively with retained stones requiring intervention 2

Critical Pitfalls to Avoid

Common errors that compromise outcomes:

• Performing routine imaging in low-risk patients: Wastes resources and does not improve outcomes—only 0.47% of patients with normal preoperative labs have CBD stones 3
• Relying on imaging instead of proper surgical technique: The critical view of safety is the primary injury prevention strategy, not adjunctive imaging 1
• Attempting complex repairs intraoperatively: If bile duct injury is detected, place a drain and transfer to experienced HPB surgeon rather than attempting immediate repair 1
• Ignoring improving liver function tests: Normalizing LFTs before surgery have significant negative predictive value for CBD stones (p=0.01) 4
• Unnecessary preoperative ERCP: ERCP carries 1-2% complication rate (up to 10% with sphincterotomy), so confirm stones with MRCP first unless stone is visible on ultrasound 1

Alternative Adjuncts

ICG fluorescence cholangiography provides real-time biliary visualization without radiation, showing no significant difference compared to IOC for visualizing cystic duct, CBD, or common hepatic duct 1, 5. However, like IOUS, routine use to reduce BDI rates is not yet recommended (GRADE 2C) 1, 5.