Midgraft curettage as a routine adjunct to salvage operations for thrombosed polytetrafluoroethylene hemodialysis access grafts

We believe that midgraft stenosis due to intimal hyperplasia of the needle puncture zone is a clinically important cause of polytetrafluoroethylene (PTFE) dialysis graft thrombosis. Our simple dialysis graft salvage technique employs conventional exploration through a venous end graftotomy, thrombectomy with a Fogarty catheter, and venous end revision as needed. Midgraft curettage is routinely performed with a Kevorkian-Younge endometrial biopsy curette. This instrument is readily available and has a box-shaped back-cutting tip ideal for thorough, safe curettage of the PTFE graft lumen. This technique results in both direct assessment and simultaneous treatment of the entire thrombosed dialysis graft. The patency rates of first salvage procedures of thrombosed PTFE dialysis grafts with and without adjunctive curettage were retrospectively compared. Patency of the curettage group was superior at 1 month (97 percent versus 71 percent) and 6 months (65 percent versus 36 percent), with ultimate crossing of the plotted curves at 10 months (p=0.053 by Wilcoxon test). It is our strong clinical impression that premature rethrombosis of PTFE dialysis grafts after salvage procedures has been greatly reduced by midgraft curettage.