Effects of blood pump flow and arteriovenous fistula blood flow rate on blood pressure and cardiac function in maintenance hemodialysis patients

Objective To study the effects of blood pump flow rate (Qb) and arteriovenous fistula blood flow rate (Qa) on blood pressure and cardiac function in maintenance hemodialysis patients. Methods A total of 120 patients who underwent hemodialysis in our hospital from January 2017 to January 2019 were enrolled and analyzed. The patients were divided into low-flow groups (Qb<220 mL/min, Qa<1000 mL/min) and high-flow group (Qb ≥ 220 mL/min, Qa ≥ 1000 mL/min) according to the median flow rate. The cardiac function parameters of the patients were measured by ultrasonic dilution method at 30 minutes before and after dialysis. Multiple linear regression models were used to analyze the correlation of variables with blood pressure and cardiac function parameters. Results The results of cardiac function tests showed that Qa, cardiac output (CO), cardiac index (CI) and central blood volume (CBV) at 30 minutes after dialysis were significantly lower than those at 30 minutes before dialysis (P<0.05), and the peripheral vascular resistance (PVR) was higher than that at 30 minutes before dialysis (P=0.018). There were no significant differences in heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP) and Qb (P>0.05). At 30 minutes before dialysis, the DBP and MAP in the high-flow group were higher than those in the low-flow group (P<0.05); at 30 minutes after dialysis, compared with the low-flow group, the SBP, DBP and MAP in the high-flow group were higher (P<0.05); and the SBP, MAP, CO, CI, and CBV in the Qa high-flow group were higher than those in the Qa low-flow group, but the PVR was lower (P<0.05). The results of the multiple linear regression model showed at 30 minutes after dialysis, Qb was significantly correlated with SBP and MAP (P<0.05); Qa was significantly correlated with CO, CI, HR, and PVR (P<0.05). Conclusions Qb ≥ 220 mL/min and Qa ≥ 000 mL/min would have a certain impact on the patient's blood pressure and cardiac function indicators.