Purpose: To evaluate the incidence and management of catheter occlusion in implantable arm ports.
Materials and methods: Findings were prospectively examined in 391 patients in whom 393 arm ports were placed. The indications for port placement included chemotherapy (n = 347), antibiotic administration (n = 35), combination chemotherapy/antibiotic use (n = 7), transfusion (n = 3), and phlebotomy (n = 1). Of the total catheters, 323 (82.2%) underwent tip modification prior to placement. Malfunctioning catheters were usually treated with urokinase instillation.
Results: Three hundred ninety-three devices were implanted with 247 mean days of catheter use (total, 97,256 days; range, 1-694 days). The overall incidence of catheter occlusion was 0.14 per 100 catheter days. A single catheter occlusion occurred in 90 (22.9%) catheters, with a mean of 90.1 days before the event. A second occlusion occurred in 36 (9.2%) of the above catheters, with a mean of 60.1 catheter days before the second event. Eighty-five (24.0%) of the 347 cancer patients had at least one occlusive event, yielding a complication rate of 0.098 per 100 catheter days at risk (95% confidence interval [CI]; 0.079-0.114). Of the 35 patients receiving antibiotics, three (8.6%) had at least one occlusive event. This represented a complication rate of 0.032 per 100 catheter days at risk (95% CI; 0.010-0.061). Seventeen (24.3%) of the nonmodified catheters developed an occlusion versus 72 (22.3%) of the modified (P > .05; Fisher exact test). Of the catheters with a first occlusive event, 75 (98.7%) were treated successfully with urokinase instillation. Four (1.0%) patients developed symptomatic subclavian vein thrombosis. No bleeding complications occurred.
Conclusion: Catheter occlusion is a common complication of long-term arm port placement, with a significantly higher incidence in the cancer patients in our series (P <. 05, Fisher exact test). Catheter tip modification, however, does not considerably affect the incidence of occlusion. Low-dose urokinase therapy is a safe and efficacious treatment of catheter occlusion, obviating the need for catheter removal.