Comparison of different methods to assess fistula flow

Background: We compared three access flow (AF) monitoring techniques: blood dilution using ultrasound (US), blood temperature monitoring (BTM), and online clearance monitoring (OCM), and investigated the impact of dialyzer blood flow (Q B), measurement time point and patient's position. Methods: US, BTM and OCM were performed in 20 hemodialysis (HD) patients at Q(B)300. OCM was unreliable for measuring AF and was therefore further omitted. US and BTM measurements were repeated in 10 patients at Q(B)200 ml/min, in 15 patients at the first weekly HD start and end and at the midweek HD start, and switching position during midweek HD. Results: AFs of 1,104 +/- 607 (US) and 1,264 +/- 664 ml/min (BTM) significantly correlated. No differences were found comparing AF at Q(B)300 and Q(B)200. AF decreased from HD start to end, while no difference was found changing patient's position. Conclusion: AFs by BTM and US correlated well and may be measured at Q(B)200-300 in all measured positions. Copyright (C) 2010 S. Karger AG, Base