Prevention of central venous catheter associated thrombosis using minidose warfarin in patients with haematological malignancies

Abstract
Thrombosis is a well‐recognized complication following insertion of central venous catheters and is associated with significant morbidity. In an attempt to reduce line‐associated thrombosis, 108 consecutive patients with haematological malignancies were commenced on prophylactic ‘minidose’ warfarin, 1 mg/d, at the time of line insertion. This group of patients were compared with a historic group of 115 consecutive patients who had not received warfarin. Clinically‐suspected venous thrombosis was confirmed by Doppler ultrasound or venography. Patients taking prophylactic warfarin had their prothrombin time measured three times per week with the aim of maintaining an INR < 1.6. Five (5%) of the 108 patients who received minidose warfarin developed a thrombosis, at a median of 72 d (range 5–166) from the time of catheter insertion. In the 115 patients who were not anticoagulated 15 (13%) developed a catheter‐associated thrombosis at a median of 16 d (range 1–35). There was a significant reduction in line‐associated thrombosis in patients receiving warfarin (P = 0.03). These data suggest that minidose warfarin reduces the incidence of central venous catheter related thrombosis in patients with haematological malignancies.