Influence of high blood access flow on central hemodynamics and cardiac function in maintenance hemodialysis patients with a distal radiocephalic fistula: A one-year prospective study

Abstract

BACKGROUND: The aim of this study was to investigate the influence of access flow (Qa) on central hemodynamics and cardiovascular function in maintenance hemodialysis (MHD) patients with a distal radiocephalic fistula (RCF). METHODS: A total of 73 eligible MHD patients participated in this prospective observational study. Blood pressure, central blood volume (CBV), peripheral resistance (PR), cardiac output (CO), cardiac index (CI), load of left ventricle (LLV), Qa, and cardiopulmonary recirculation (CPR) were measured using a HDO2 monitor at the initiation (1st test) and termination (2nd test) of a single hemodialysis (HD) session at the beginning of treatment. Patients were divided into low flow (LF, Qa < 1050 ml/min) and high flow (HF, Qa ≥ 1050 ml/min) groups based on the median Qa value in the 1st test. These parameters were measured again at a one-year follow-up (3rd test), and the number of cardiovascular events and deaths were recorded. RESULTS: The Qa was 663.9 ± 259.2 ml/min in the LF group and 1800.1 ± 633.0 ml/min in the HF group. PR was higher and CPR was lower in the LF group as compared to the HF group (p < 0.05). In the single HD session, systolic blood pressure (SBP) and CBV significantly decreased, and PR increased, in the HF (p < 0.05), but not in the LF group. CO, CI and LLV decreased significantly during the single HD session in both groups (p < 0.05). At the one-year follow-up, CO, CI and LLV decreased significantly in the HF (p < 0.05), but not in the LF group, and no variations in SBP, CBV, PR and CPR were detected for either group. Furthermore, the incidence of cardiovascular events was significantly higher in the HF group compared to the LF group at the one-year follow-up. CONCLUSION: MHD patients with higher flow RCF are more likely to experience deteriorated cardiac function and an increased incidence of cardiovascular events. However, further clinical trials with a larger sample size and a longer follow-up period will be needed to verify these results.