Steps to Flush a Pigtail Catheter
Flush pigtail catheters with 0.9% normal saline using a 5-10 mL syringe, employing a turbulent (pulsatile) flushing technique with strict aseptic technique to maintain patency and prevent infection. 1
Pre-Flushing Preparation
Hand Hygiene and Aseptic Setup
- Perform hand hygiene before the procedure 1, 2
- Prepare supplies while maintaining sterility
- Don clean or sterile gloves 1
- Place a clean or sterile pad/towel under the catheter 1
Hub Disinfection ("Scrub the Hub")
- Ensure the catheter clamp is closed before accessing 1
- Remove the Luer lock cap
- Clean the hub vigorously with chlorhexidine (or povidone-iodine if chlorhexidine not tolerated) 1, 2
- Ensure the disinfected hub does not touch nonsterile surfaces 1
- If using needleless caps, follow manufacturer's recommendations 1
Flushing Procedure
Aspiration First
- Attach a syringe to the hub
- Unclamp the catheter
- Aspirate 2-5 mL of blood and any locking solution from the lumen 1
- Reclamp the catheter 1
Saline Flush Technique
- Attach a 5-10 mL syringe filled with 0.9% normal saline 1
- Unclamp the catheter
- Use a turbulent (pulsatile) flushing technique - this involves a push-pause-push motion rather than continuous pressure 1, 3
- Flush with the full volume (typically 10 mL) to ensure blood is completely cleared from the lumen 1
Post-Flush Locking (If Applicable)
- After flushing with saline, if the catheter will remain closed >8 hours, follow institutional protocol for locking solution 1, 4
- For most central venous catheters in frequent use, saline locking is sufficient 4
- Heparinized solutions (50-500 units/mL) may be used for implanted ports or open-ended catheters per manufacturer instructions 4
Final Steps
- Clamp the catheter while maintaining positive pressure (clamp before removing syringe) 1
- Remove the syringe
- Clean the hub again 1
- Apply a sterile Luer lock cap 1
- Discard used supplies 1
Critical Pitfalls to Avoid
Never use syringes smaller than 5 mL - smaller syringes generate excessive pressure that can rupture the catheter 1
Do not force flush if resistance is encountered - this may indicate fibrin buildup, thrombus, or catheter malposition. Instead, use gentle back-and-forth irrigation motion before attempting full flush 1
Avoid mixing heparin directly with lipid-containing solutions - always interpose a saline flush between lipid infusions and heparin 4
Do not touch the disinfected hub after cleaning - this breaks aseptic technique and increases infection risk 1, 2
Maintenance Flushing Frequency
- After each use or blood sampling: Flush immediately 5
- Pigtail catheters not in active use: Weekly flushing for small caliber (≤5 Fr), every 3-4 weeks for large caliber (≥6 Fr) 4
- Tunneled catheters and PICC lines: Weekly when not in use 5
- Implanted ports: Every 4 weeks when not in active use 5
The turbulent flushing technique is particularly important as it creates turbulence within the catheter lumen that more effectively clears fibrin deposits and blood products compared to continuous pressure flushing 1, 3. This technique, combined with aseptic non-touch methodology, has been shown to reduce catheter-related bloodstream infections 3.