Efficacy of low-dose alteplase for treatment of hemodialysis catheter occlusions

Traditionally, alteplase 2 mg/lumen doses have been used to treat central venous catheter (CVC) occlusions. On January 20, 2004, our hemodialysis (HD) unit implemented a new protocol to utilize alteplase 1 mg/lumen doses for catheter occlusion. The objectives were to 1) assess the efficacy of low-dose alteplase in restoring HD catheter patency; 2) determine the duration of CVC patency as determined by need for further alteplase doses, or radiological or surgical line interventions; and 3) evaluate the financial implications of the new protocol. The study was a prospective, open-label trial of 50 consecutive HD patients with permanent, tunnelled CVC lines. A treatment course consisted of 1 or 2 doses of alteplase instilled for 60 minutes then aspirated or as an overnight (48-72 hour) dwell until the next HD. The patient's first alteplase dose following implementation of the new protocol was evaluated. Patients were followed for two months to record need for further al-teplase treatment courses, and four months to document radiological or surgical line interventions. The primary outcome was to assess successful restoration of catheter patency defined as the ability of alteplase to restore or maintain HD blood flow rate at or above 300 mL/minute. A financial analysis compared alteplase costs for 11 months prior to and after implementation of the new protocol. Alteplase 1 mg/lumen doses restored catheter patency in 72% of HD patients with one dose, increasing to 83% with a second dose. Sixty-two percent of patients required a subsequent alteplase course with a median time to next treatment of 14 days and a median of 2 courses/patient. Radiological interventions were ordered in 38% of patients resulting in 8 lines replacements and 7 line strippings. Financial savings with the new low-dose protocol were approximately CDN dollar 22,000. Low dose alteplase 1 mg/lumen successfully treated occlusion of permanent hemodialysis catheters, with a resulting cost reduction.