An effective algorithm for occluded catheter treatment using urokinase

An effective algorithm for occluded catheter treatment using urokinase

Managing catheter occlusions effectively is vital in clinical environments, as maintaining catheter patency is necessary to avoid treatment interruptions. The current multidisciplinary approach to catheter management combines clinical examination, imaging studies and targeted thrombolytic therapy to address catheter dysfunctions. Syner-KINASE® (urokinase) – a human urokinase protein and plasminogen activator – is a clinically proven thrombolytic agent for restoring catheter function.

Syner-KINASE in action: evidence from the PASSPORT studies

The Prospective Audit to Study urokinaSe use to restore Patency in Occluded centRal venous caTheters (PASSPORT 1 and 2) studies demonstrated Syner-KINASE’s effectiveness as a clot-dissolving medication as part of a standardised, algorithm-based approach to catheter management.

PASSPORT 1 study1

Objective: The PASSPORT 1 study aimed to evaluate the efficacy and tolerability of Syner-KINASE in restoring patency in tunnelled central venous access devices (CVADs) used for haemodialysis patients.

The study focused on standardising the dose regimens of urokinase lock and infusion to achieve optimal catheter blood flow during dialysis.

Results: The study found a trend towards improved outcomes with higher doses of urokinase per lumen, with success rates of 84 % for a 12,500 IU lock, 87 % for higher dose lock protocols, 91 % for infusion with 100,000 to 125,000 IU, and 94 % for 200,000 IU.

However, the difference between push/dwell locks and high dose infusion was not statistically significant. No urokinase-related side effects were reported.

PASSPORT 2 study2

Objective: The PASSPORT 2 study aimed to evaluate the tolerability and effectiveness of standardised doses of Syner-KINASE in restoring patency in dysfunctional CVADs used in oncology and haematology patients.

The study focused on cases of both persistent withdrawal occlusion (PWO) and total occlusion (TO) where non-thrombotic causes of catheter dysfunction had been excluded.

Results: The study included 117 patients across eight centres, and found that Syner-KINASE was effective in restoring catheter patency in 80 % of PWO cases and 88 % of TO cases.

The success rate was dose dependent, with 83 % success at 5,000 IU, 89 % at 10,000 IU, and 92 % at the higher dose of 25,000 IU per lumen.

No adverse events related to urokinase were reported.

Standardised approaches to catheter management

The Syner-KINASE algorithms below were developed based on evidence from the PASSPORT 1 and PASSPORT 2 studies. They provide clear, step-by-step approaches to restoring catheter function in varied clinical settings.

PASSPORT 1: haemodialysis catheter management

  1. Initial assessment: Conduct a clinical evaluation and/or imaging to rule out non-thrombotic causes of catheter dysfunction, such as mechanical issues or infection.
  2. First-line intervention: Use a push lock or dwell lock technique with Syner-KINASE at 12,500 to 25,000 IU per catheter lumen.
  3. Secondary intervention: If initial measures fail, escalation to a high dose urokinase infusion (100,000 to 200,000 IU) may be required.
  4. Further management: In cases of persistent dysfunction, infusion can be repeated. If this is unsuccessful, consult with a vascular access MDT or interventional radiologist, and consider catheter replacement or alternative access.

For a detailed stepwise approach, refer to the algorithm for renal catheter management.

PASSPORT 2: oncology and haematology catheter management

  1. Initial assessment: Assess for non-thrombotic causes of catheter dysfunction, such as drug precipitates or lipid residues. After excluding non-thrombotic causes, attempt a flush trial before proceeding with thrombolysis.
  2. Management of persistent withdrawal occlusion (PWO):
    • Use a urokinase lock technique (push lock or dwell lock) with 5,000 to 25,000 IU per lumen.
  3. Management of total occlusion (TO):
    • Use a urokinase lock technique (push lock or dwell lock) with 5,000 to 25,000 IU per lumen.
    • A three-way tap method may be necessary to initiate thrombolysis in fully occluded catheters.
  4. Further management: If patency is not restored, further escalation may involve increasing the lock dose, considering a three-way tap method for resistant TOs, or catheter replacement or removal.

Achieving high catheter clearance success rates

Achieving high catheter clearance success rates

With an initial clearance rate of up to 91 % when using infusion with doses of 100,000 to 125,000 IU – and further improvements with subsequent treatments – Syner-KINASE is highly effective in restoring catheter function, and helps to reduce the need for costly and disruptive catheter replacements.1 It is a widely used and effective option among thrombolytic therapy drugs for targeting thrombotic catheter occlusions.

Urokinase and NHS guidelines

Urokinase and NHS guidelines

The British National Formulary (BNF) provides guidance on the use of urokinase, describing it as a thrombolytic agent indicated for the treatment of thrombotic occlusions, including catheter clearance. Urokinase is administered to restore catheter patency by breaking down fibrin-rich clots, helping to maintain vascular access. For recommended dosage and administration guidelines, refer to the BNF entry on urokinase.3 The use of urokinase for the treatment of thrombotic occlusions is also recommended in guidelines published by other healthcare organisations such as the UK Kidney Association.4

Discover more about Syner-KINASE

Discover more about Syner-KINASE

Medical stent partially blocked by arterial plaque buildup with fibrous tissue, visualized in a 3D rendering to illustrate cardiovascular disease and artery obstruction.

Learn about catheter thrombosis and why thrombolytic therapy is essential

Syner-Kinase® Human Urokinase vials and packaging in 10,000, 25,000, and 100,000 IU doses

Find out more about
Syner-KINASE®

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Watch expert-led discussions on thrombolysis for catheter blockages

Have questions or need more information?

Have questions or need more information?

Adverse events should be reported. Reporting forms and information can be found at www.mhra.gov.uk/yellowcard. 

Adverse events should also be reported to Syner-Med (PP) Ltd. Tel: +44 (0)208 655 6380

For Syner-KINASE prescribing information, click here

References

  1. Kumwenda MJ, et al. Prospective audit to study urokinase use to restore patency in occluded central venous catheters (PASSPORT 1). The Journal of Vascular Access. 2019;20(6):752-759. doi:10.1177/1129729819869095
  2. Kumwenda MJ, et al. Prospective audit to study urokinase use to restore patency in occluded central venous catheters in haematology and oncology patients (PASSPORT 2). The Journal of Vascular Access. 2020;22(4):568-574. doi:10.1177/1129729820950997
  3. Urokinase. NICE British National Formulary (BNF). https://bnf.nice.org.uk/drugs/urokinase/
  4. UK Kidney Association. 2023. UK Kidney Association Clinical Practice Guidelines, Vascular Access for Haemodialysis. https://www.ukkidney.org/sites/default/files/FINAL%20FORMATTED%20Vascular%20access%20for%20haemodialysis%20April%202023.pdf