RESUMO
Arteriovenous fistulas (AVFs) play an important role in access for hemodialysis, yet premature thrombosis is a challenge. This study identifies factors influencing primary patency in a series of AVF creations. Postoperative systolic blood pressure (BP) was of principal interest; demographical information, comorbidities, smoking status, warfarin, aspirin, clopidogrel, and statins were considered. A retrospective review of AVF creations performed by one surgeon between January 2008 and September 2010 was conducted. Fistula patency was denoted by a bruit and measured at 3 weeks and 12 months after surgery. One hundred and fifty-one AVF creations were studied; 134 fistulas (88.7%) were patent at 3 weeks and 85 (56.3%) at 12 months. The odds ratio (OR) for thrombosis at 12 months was 0.16 (95% CI: 0.04, 0.62; p = 0.008) among patients with a postoperative systolic BP of 120-139 mmHg compared with those with a BP of ≤ 119 mmHg. Patients taking warfarin yielded an OR of 5.71 at 3 weeks (95% CI: 1.20, 27.11; p = 0.028), and 3.33 at 12 months (95% CI: 1.01, 10.99; p = 0.048). No other variables were statistically significant. Patients with postoperative systolic BP of 120-139 mmHg showed a reduction in fistula thromboses compared with patients with a systolic BP of ≤ 119 mmHg. Patients on warfarin were less likely to maintain a patent fistula.