Use of heparin versus lepirudin flushes to prevent withdrawal occlusion of central venous access devices

Study Objective. To determine whether lepirudin flushes are more effective than heparinized saline in preventing withdrawal occlusion of central venous access devices. Design. Randomized, double-blind clinical trial. Setting. Research institution-tertiary referral center. Patients. Forty-nine adults undergoing bone marrow transplantation for hematologic malignancies or metastatic solid tumors. Intervention. Twenty-four patients received heparin and 25 received lepirudin flushes. The heparin dose was 3 ml of porcine heparin 100 U/ml (300 U) per catheter lumen at least once/day; the lepirudin dose was 3 ml of lepirudin 100 pg/ml (300 pg) per catheter lumen at least once/day. After 3-4 weeks, all 49 patients received the heparin flushes. Measurements and Main Results. Efficacy was assessed by the frequency with which the patients were treated with alteplase instillations for withdrawal occlusion of their central venous access devices during the first 4 months of catheterization. Three (12.5%) patients treated with heparin alone and five (20%) treated initially with lepirudin required alteplase instillations for an estimated relative risk with lepirudin versus heparin of 1.6 (95% confidence interval [CI] 0.40-13.86, p=0.70). Conclusion. Lepirudin was not more effective than heparin, which may have been related to the conservative dose of lepirudin administered. However, higher lepirudin doses are likely to incur an unacceptable risk of systemic anticoagulation.