What is the proper technique for flushing a biliary (bile) drain in a patient with a biliary drain?

How to Flush a Biliary Drain

Flushing a biliary drain involves instilling sterile saline solution through the external catheter to maintain patency and prevent occlusion, though this technique is primarily relevant for external or nasobiliary drains rather than internal stents.

Indications for Drain Flushing

• Nasobiliary drains have the specific advantage of allowing repeated flushing to maintain patency, along with bile aspiration for microbiologic analysis and cholangiographic evaluation 1
• Flushing is indicated to prevent catheter occlusion, which represents one of the delayed complications of percutaneous biliary drainage 2
• The technique can be used for retained common bile duct stones with a T-tube in situ as part of non-operative management 3

Flushing Technique

• Use continuous infusion of heparinized saline solution through the external drain catheter 3
• The infusion should be performed with sterile technique to prevent introducing infection into the biliary system 2
• For retained stones, parenteral aminophylline may be administered concurrently to induce relaxation of the sphincter of Oddi, facilitating stone passage 3
• This approach achieved complete duct clearance in 61% of patients (17 of 28) with retained stones, with no mortality 3

Important Considerations by Drain Type

• Internal biliary stents (plastic or metal) do not require routine flushing as they are designed to remain patent without external manipulation 1
• External percutaneous drains and nasobiliary tubes are the primary drain types that benefit from flushing 1, 2
• When percutaneous drainage is deployed, avoid permanent external drains when possible, as they increase patient discomfort and complication risk 1

Safety and Monitoring

• Monitor for signs of cholangitis during and after flushing, including fever, abdominal pain, and changes in drain output 1, 2
• Acute complications from manipulation of biliary drains include septicemia, bleeding, and bile leakage, occurring in 1-5% of cases 2
• If resistance is encountered during flushing, stop immediately and obtain imaging to assess for catheter malposition or duct obstruction 2

Duration and Frequency

• Flushing can be performed in the early postoperative period with hospital stay prolongation of no more than 1 week 3
• The technique represents a safe first-line approach before more invasive interventions like percutaneous stone extraction 3
• For long-term external drains, regular flushing helps prevent the delayed complication of catheter occlusion with subsequent cholangitis 2

Critical Pitfalls to Avoid

• Never inject contrast or flush under high pressure, as this may cause cholangio-venous reflux and exacerbate septicemia 4
• Do not attempt to flush internal stents, as this requires endoscopic or percutaneous access and risks stent migration 1
• Avoid flushing in patients with active cholangitis until appropriate antibiotics have been administered and clinical improvement is evident 1
• Contraindications to drain manipulation include bleeding disorders, which increase risk of hemorrhagic complications 2