When a catheter becomes dysfunctional, it is often related to an occlusion1

Catheter occlusion is the most common noninfectious complication in the long-term use of central lines.1

Indicators of catheter occlusion include1,2:

Inability to infuse fluids
Lack of free-flowing blood return
Increased resistance when flushing
Sluggish flow

1 out of 4 catheters may become occluded3

Occlusions are either thrombotic or nonthrombotic.3

Pie chart of thrombotic (58%) vs (nonthrombotic) 42%

References:

McKnight S. Nurse's guide to understanding and treating thrombotic occlusion of central vascular access devices. Medsurg Nurs. 2004;13:377-382.
Hadaway LC. Reopen the pipeline. Nursing. 2005;35:54-61.
Stephens LC, Haire WD, Kotulak GD. Are clinical signs accurate indicators of the cause of central catheter occlusion? J Parent Enteral Nutr. 1995;19:75-79.

Indication: For restoration of function to central venous access devices (CVADs) as assessed by the ability to withdraw blood.

Safety Information: Cathflo Activase should not be administered to patients with known hypersensitivity to Alteplase or any component of the formulation. In the clinical trials, the most serious adverse events reported after treatment were sepsis, gastrointestinal bleeding, and venous thrombosis. Cathflo Activase should be used with caution in the presence of known or suspected infections in the catheter.

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