What is the recommended dose of Indocyanine Green (ICG) for a cholecystectomy?

ICG Dosing for Cholecystectomy

For laparoscopic cholecystectomy, administer 2.5 mg (0.5 mg/kg) of indocyanine green intravenously 2-6 hours before surgery for optimal biliary visualization, though administration 20-30 minutes preoperatively at the same dose provides adequate visualization and is acceptable when time is limited. 1, 2

Recommended Dosing Protocols

Standard Intravenous Administration

• The FDA-approved dose is 0.5 mg/kg body weight, which translates to approximately 2.5 mg for an average adult, dissolved in 5 mL of aqueous solvent to create a 5 mg/mL solution 1
• For biliary visualization during cholecystectomy, doses up to 2.5 mg intravenously have been validated in clinical practice 3, 2

Timing Considerations

• Administration 2-6 hours before surgery provides superior common bile duct visualization (97.1% success rate) compared to other timing intervals 2
• Administration at induction of anesthesia (20-30 minutes before) achieves 85-86% visualization success and is acceptable when earlier administration is not feasible 2
• Delayed administration (≥24 hours) at 10 mg significantly reduces liver background fluorescence but requires advance planning 4

Dose Optimization Based on Recent Evidence

• A 2023 randomized controlled trial demonstrated that 0.1 mg ICG administered 30 minutes preoperatively provides the highest bile duct-to-liver ratio and optimal cholangiography 5
• Lower doses (0.025-0.1 mg) consistently show better bile duct-to-liver contrast ratios than higher doses (0.25-2.5 mg) at all surgical timepoints 5
• The simplified protocol of 2.5 mg (1 cc) administered 2-6 hours preoperatively is recommended for its reproducibility and ease of use in routine practice 2

Alternative Administration Routes

Direct Intrabiliary Injection

• For patients with existing biliary access (PTGBD, ENBD), intrabiliary injection of 0.025 mg ICG provides 100% visualization success compared to 83.3% with intravenous administration 3
• Direct gallbladder puncture during surgery with 0.025 mg ICG is effective but requires additional intraoperative manipulation 3

Clinical Context and Guidelines

Guideline Recommendations

• The World Society of Emergency Surgery recommends selective use of ICG cholangiography during difficult laparoscopic cholecystectomy or when bile duct injury is suspected (Grade 2B recommendation) 6, 7
• ICG cholangiography should be used as an adjunct to, not a replacement for, the critical view of safety technique 7
• The American College of Surgeons recommends ICG cholangiography in cases with difficult anatomy, acute cholecystitis, or when intraoperative cholangiography cannot be performed 7

Important Caveats

• ICG is cleared by the liver and excreted in bile, making it ideal for biliary visualization but requiring direct ureteral injection if ureteral visualization is needed 6
• Liver background fluorescence is the major limitation, particularly with higher doses and early imaging 4
• Despite its benefits, routine ICG use has not been shown to significantly reduce bile duct injury rates in large surveys of experienced surgeons 6, 7
• No adverse events related to ICG administration at these doses have been reported in cholecystectomy series 3, 8

Practical Implementation

Preparation and Administration

• Dissolve 25 mg ICG powder with exactly 5 mL of aqueous solvent provided to create a 5 mg/mL solution 1
• Inject rapidly into an arm vein without allowing extravasation 1
• For optimal results with 2.5 mg dose, administer 2-6 hours before incision 2
• If time-constrained, administer 2.5 mg at anesthesia induction (20-30 minutes before) 2

Visualization Technique

• Use near-infrared fluorescence imaging systems compatible with ICG (excitation/emission spectra 800-850 nm) 1, 3
• Local compression with transparent devices improves visualization of the cystic duct-common bile duct confluence 8
• Re-infusion of ICG intraoperatively can identify cystic artery flow 7-10 seconds after administration 8