Thrombolytic therapy for central venous catheter occlusion

Abstract

Background: Long-term central venous catheters have improved the quality of care for patients with chronic illnesses, but are complicated by obstructions which can result in delay of treatment or catheter removal.

Design and methods: This paper reviews thrombolytic treatment for catheter obstruction. Literature from Medline searches using the terms "central venous catheter", "central venous access device" OR "central venous line" associated with the terms "obstruction", "occlusion" OR "thrombolytic" was reviewed. Efficacy of thrombolytic therapy, central venous catheter clearance rates and time to clearance were assessed.

Results: Alteplase, one of the current therapies, clears 52% of obstructed catheters within 30 min with 86% overall clearance (after 2 doses, when necessary). However, newer medications may have higher efficacy or shorter time to clearance. Reteplase cleared 67-74% within 30-40 min and 95% of catheters overall. Occlusions were resolved in 70 and 83% of patients with one and 2 doses of tenecteplase, respectively. Recombinant urokinase cleared 60% of catheters at 30 min and 73% overall. Alfimeprase demonstrated rapid catheter clearance with resolution in 40% of subjects within 5 min, 60% within 30 min, and 80% within 2 h. Additionally, urokinase prophylaxis decreased the incidence of catheter occlusions from 16-68% in the control group to 4-23% in the treatment group; in some studies, rates of catheter infections were also decreased in the urokinase group.

Conclusions: Thrombolytic agents successfully clear central venous catheter occlusions in most cases. Newer agents may act more rapidly and effectively than currently utilized therapies, but randomized studies with direct comparisons of these agents are needed to determine optimal management for catheter obstruction.

Figure 1.

Diagram of the mechanism of action of thrombolytic medications. Streptokinase binds plasminogen, which converts free plasminogen to plasmin. Alteplase, urokinase, recombinant urokinase (r-uk), reteplase and tenecteplase cleave plasminogen to produce plasmin, a process that is inhibited by plasminogen activator inhibitor. Alfimeprase cleaves fibrin directly to produce fibrin degradation products, a process inhibited by α2 macroglobulin.

Figure 2.

Average catheter clearance after 30 min with each of the thrombolytic medications evaluated in this study with 95% confidence intervals.

Figure 3.

Cumulative incidence of successful catheter clearance for each of the thrombolytic medications evaluated after a maximum of 2 treatment doses, calculated as a weighted average with 95% confidence intervals. With each dose, maximum dwell times of 30 and 60 min were utilized for recombinant urokinase and reteplase, respectively. Alteplase, alfimeprase, and tenecteplase used dwell times of a maximum of 120 min.