What are the technical considerations for a right percutaneous transhepatic biliary drainage (PTBD) in an undilated system with perihepatic fluid present?

Technical Considerations for Right PTBD in Undilated System with Perihepatic Fluid

For right percutaneous transhepatic biliary drainage (PTBD) in an undilated system with perihepatic fluid, a combined ultrasound and fluoroscopy-guided approach using the "parallel technique" is recommended for optimal safety and success. 1

Pre-Procedure Considerations

• Assess coagulation parameters prior to the procedure, as PTBD is contraindicated in patients with uncorrected coagulopathy due to increased bleeding risk (approximately 2.5% of cases) 2
• Evaluate the perihepatic fluid carefully, as moderate to massive ascites is a relative contraindication for PTBD 2
• Consider prophylactic antibiotics to prevent post-procedural cholangitis, especially important in the setting of biliary obstruction 3

Technical Approach for Undilated System

• Use a combined ultrasound and fluoroscopy guidance technique:

  • Begin with ultrasound guidance for initial bile duct puncture 1, 4
  • Employ the "parallel technique" - puncture along the course of the targeted bile duct or portal vein when the bile duct is not well visualized 1
  • Once access is achieved, switch to fluoroscopy for guidewire manipulation and catheter placement 1, 4

• For right-sided approach in undilated systems:

  • Target the right posterior or anterior segmental ducts under ultrasound guidance 5
  • Fluoroscopy-guided approach from the right side has shown higher success rates (91.9%) compared to ultrasound-only guidance (75%) 5
  • Use a 22G Chiba needle for initial access to minimize trauma in the undilated system 6

Managing Perihepatic Fluid Challenges

• The presence of perihepatic fluid increases the risk of biliary peritonitis (reported in approximately 5.2% of high-risk cases) 6
• Consider a more cranial approach to avoid traversing the fluid collection 6
• Minimize the number of liver punctures - aim for successful cannulation in fewer attempts (mean number in experienced centers: 1.57) 4
• Ensure proper catheter fixation to prevent displacement into the peritoneal space 3

Post-Procedure Management

• Monitor for complications, particularly:
  • Transient hemobilia (most common minor complication) 1
  • Fever and signs of infection 1
  • Biliary peritonitis (major complication in 5.2% of high-risk cases) 6
• Evaluate drainage output and appearance regularly 7
• Consider drain removal when output decreases to less than 300 mL/24h 7

Special Considerations for Undilated Systems

• Technical success rates of 90-100% can be achieved even in undilated systems with proper technique 1, 6
• The left-sided approach may be preferable if right-sided access is technically challenging, with success rates of 95.8% for ultrasound-guided left approach 5
• In cases of bile leak with undilated ducts, endoscopic approaches should be considered first when feasible 2, 3
• If no improvement occurs after percutaneous drainage, consider endoscopic management with ERCP, biliary sphincterotomy, and stent placement 2

Potential Pitfalls and How to Avoid Them

• Multiple puncture attempts increase the risk of complications - use the "parallel technique" to improve first-pass success 1
• Be vigilant for signs of biliary peritonitis, which requires urgent management 6
• Consider the higher risk of major complications with fluoroscopy-guided PTBD compared to ultrasound-guided approaches 5
• In cases where PTBD fails or is complicated by the undilated system, consider alternative approaches such as EUS-guided biliary drainage when expertise is available 2