Abstract: 【Abstract】Objective To observe the relationship between blood access from arteriovenous fistula (Qa) and the changes of cardiac output (CO) and mean arterial pressure (MAP) in maintenance hemodialysis (MHD) patients. Method A total of 54 MHD patients with arteriovenous fistula (AVF) were enrolled in this
study. Variations of Qa by ultrasound dilution technique, CO, and MAP were observed at 30 minutes, 2 hours, and 3 hours after starting a hemodialysis session to study Qa affected by the changes of CO and MAP in a hemodialysis session. Result Qa, CO and MAP changed insignificantly at the 3 time points in a hemodialysis session (P>0.05). Qa was positively correlated with CO and MAP at the same time point (P<0.05)., The percentage of Qa variation within the 3 time points (△Qa1-3%) was positively correlated with the percentage of CO variation (△CO1-3%) (r=0367, P=0.009), and the percentage of MAP variation (△MAP1-3%) (r=0.455, P=0.001). The variation of Qa and CO were significantly greater in patients having ultrafiltration volume of > 5% dry body weight than in those having ultrafiltration volume of <5% dry body weight (P＜0.05). Conclusion Qa, CO and MAP were relatively stable in a hemodialysis session. Qa was positively correlated with CO and MAP. The increase of ultrafiltration volume in a session may result in the changes of Qa and CO and thus interfere with the stability of hemodynamics.

Key words: maintenance hemodialysis, arteriovenous fistula, accessflow, ultrasound dilution technology