Reteplase for dysfunctional hemodialysis catheter clearance.

Study Objective: To evaluate the efficacy of reteplase administration in clearing hemodialysis catheters.

Design: Open-label, uncontrolled, observational trial.

Setting: University medical center.

Patients: Thirty-four patients with end-stage renal disease undergoing long-term hemodialysis.

Intervention: Patients had dual-lumen, cuffed, tunneled dialysis catheters placed for long-term vascular access. Reteplase 3 U was instilled into each catheter lumen (total dose 6 U) in the first 20 episodes, 2 U in each catheter lumen (total dose 4 U) in the next 20, and 0.5 U in each catheter lumen (total dose 1 U) in the final 45.

Measurements And Main Results: Over 12 months, 85 episodes of catheter dysfunction were documented. Catheter dysfunction was defined as absence of flow from the catheter lumen, inability to aspirate heparin from the lumen, blood flow rates below 150 ml/minute, or venous pressure greater than 250 mm Hg at blood flow rates below 200 ml/minute. Reteplase was instilled into the catheter lumens and allowed to dwell there until the next hemodialysis session. Successful catheter recanalization was defined as return of aspiration and infusion function allowing dialysis to be completed at blood flow rates above 300 ml/minute. Reteplase restored catheter function in 74 (87%) instances of catheter dysfunction. In the first 40 episodes in which 4- or 6-U doses were given, catheter function was restored in 36 instances (90%). There was no difference in restoration of catheter function between 4 U (18/20, 90%) and 6 U (18/20, 90%). In the last 45 cases in which 1 U was administered, function was restored in 38 catheters (84%). Mean overall dwell times were not different between the first 40 (32 +/- 7 hrs) and the last 45 episodes (33 +/- 10 hrs). The overall mean duration of catheter patency was 45 +/- 39 days. Durations of patency in the three dose groups were not significantly different (44 +/- 38, 46 +/- 40, 45 +/- 39 days). No patient suffered adverse effects related to reteplase.

Conclusion: Reteplase installation in dysfunctional hemodialysis catheters was effective in restoring catheter function in 87% of episodes. A dose of 1 U appears to be as effective as 4 and 6 U.