Patency in Arteriovenous Grafts in Hemodialysis Patients

Abstract

It is difficult to maintain a working access for patients on hemodialysis. Despite current Dialysis Outcome Quality Initiatives recommendations of "Fistula First," not everyone qualifies for a fistula, and those patients undergoing the alternative treatment, a graft, can experience graft failure. This study examines factors associated with arteriovenous graft (AVG) patency. A retrospective analysis was completed for all the patients who had an AVG during 2005 to 2010. Data were collected from electronic medical records, including date of first and subsequent interventions, salvage technique (surgical vs percutaneous), medical comorbidities, and use of antiplatelet medications (aspirin and clopidogrel). Continuous variables were compared with 2 sample t tests, and categorical variables with chi-square/Fisher exact test. Logistic regression was used to determine the odds ratio for risk factors associated with patency. A P value of <.05 was considered significant. All analyses were done using SAS 9.2 (SAS Institute Inc, Cary, North Carolina). A total of 193 unique patients had an AVG. Of the 193 patients, 64% were female, 83% were hypertensive, and 64% were diabetic. The locations of the grafts were 80% arm, 15% forearm, and 5% thigh. Configurations, including loop and straight, were 34% and 63%, respectively. Comorbidities were not associated with patency. Primary patency was not found to be different with respect to location and configuration of graft and type of intervention. Primary patency for patients taking only aspirin (n = 43) and only clopidogrel (n = 17) were significantly different from patients on a combination of aspirin and clopidogrel (n = 7), with a P = .0051 and P = .0447, respectively. Neither location nor configuration affects the primary patency of AVGs. Aspirin alone is not inferior to aspirin and clopidogrel. Further prospective studies may be warranted to establish a consensus regarding medications and patency with AVGs.