Short and long alteplase dwells in dysfunctional hemodialysis catheters

Hemodialysis catheter dysfunction (CD) is the inability to attain adequate blood pump speeds (BPS) and is attributed to thrombus or catheter malposition; alteplase (TPA) is often given in a variety of dwell times to treat CD. The purpose of this study was to determine if TPA dwell time affects short- or long-term catheter patency rates.

Sixty hemodialysis (HD) patients with CD, as defined by BPS of < 250 mL/min, were randomized to receive either 1- or > 48-hr (to subsequent HD run) TPA dwell. The primary outcomes were catheter patency (BPS of > 250 mL/min) at the subsequent HD run and catheter patency at 2 weeks. The secondary outcome was the time from study entry to the next catheter intervention (including subsequent TPA installation).

After TPA installation, a 78% overall catheter patency rate was observed at the subsequent HD run, falling to 48% patency at 2 weeks. There is no statistically significant difference between the short and long TPA dwell groups for catheter patency at the subsequent HD run (76.9% vs. 79.4%) or at 2 weeks (42.3% vs. 52.9%). Multivariate analysis demonstrates that the use of TPA on two or more previous occasions is a predictor of TPA failure both at the subsequent HD run and at 2 weeks. TPA installation achieves a median catheter function time of only 14 days, after which CD reoccurs.

This study demonstrates that although patency for the next HD run can be achieved with either short or long TPA dwell, neither is reliable in terms of long-term patency. Strategies that employ TPA for CD are temporary and allow a 2-week window during which more definitive therapies for HD access should be sought.