Early Detection of Arteriovenous Fistula Stenosis in Hemodialysis Patients through Routine Measurements of Dialysis Dose (Kt/V)

Monitoring of arteriovenous (AV) fistula to detect hemodynamically important stenosis is crucial for the prevention of AV fistula thrombosis. The aim of our study was to analyze the importance of dialysis dose (Kt/V) during online postdilution hemodiafiltration (HDF) for early detection of AV fistula stenosis.Hemodialysis patients with AV fistula were included in this study. We compared a group of 44 patients who have undergone fistulography and subsequently percutaneous transluminal angioplasty (PTA) of significant AV fistula stenosis (active group) with a group of 44 age- and sex-matched patients without PTA (control group). Observational time in both groups was the same.All patients had postdilution online HDF using a F5008 dialysis machine, which can measure online single-pool Kt/V. All data were analyzed during the performance of 2056 HDF procedures. In the active group, we found statistically significantly lower values of Kt/V, all 8 weeks before PTA. In the active group, there was a significant improvement in Kt/V in the first (p < 0.001) and second week (p = 0.049) after PTA. Three and 8 weeks after PTA, we did not find any statistically significant difference in Kt/V between both groups (p = 0.114; p = 0.058). Patients in the active group had statistically significantly lower substitution volumes and blood pump flow rates during HDF over the whole observation period before and after PTA. In contrast, there were no differences in venous pressure in the dialysis circuit between both groups throughout the observation period.In hemodialysis patients with AV fistula, treated with online HDF, routine measurements of Kt/V during each HDF are a beneficial, quick, and straightforward method for early detection of hemodynamically significant AV fistula stenosis.