Abstract: Objective  To observe the changes of hemodynamic parameters before and after hemodialysis in maintenance hemodialysis (MHD) patients, and to explore the clinical value of hemodynamic monitoring in MHD patients by comparison of clinical indicators between patients with improved and those with unimproved hemodynamics.  Methods  Patients undergoing stable MHD at the Department of Nephrology, Beijing Shunyi District Hospital were selected as study subjects. General clinical data were collected, venous blood samples were obtained before and after hemodialysis, and non-invasive hemodynamic monitoring using thoracic electrical bioimpedance was performed. Changes in hemodynamic parameters before and after dialysis and their correlations with clinical indicators were analyzed.  Results  A total of 41 patients were included.  ① Significant differences in heart rate, heart rate variability, cardiac index, thoracic fluid conductivity, pulmonary capillary wedge pressure, and systemic vascular resistance were observed before and after hemodialysis (t=0.056, 2.932, 0.998, 0.022, 0.637 and 2.653 respectively; P=0.023, 0.021, 0.015, 0.005, 0.006 and 0.030 respectively).  ② In the 27 patients with improved hemodynamic status after dialysis, mean arterial pressure, systemic vascular resistance, systolic blood pressure, and diastolic blood pressure decreased significantly post-dialysis (t=0.924, 2.136, 2.453 and 0.092 respectively; P=0.009, 0.013, 0.004 and 0.047 respectively).  ③ In the patients with improved hemodynamic status after dialysis, lower total cholesterol levels and the better control of intact parathyroid hormone (iPTH) were found, as compared those in the unimproved group (t=4.705 and 5.327; P=0.036 and 0.026).  Conclusion  Hemodynamic parameters undergo significant changes after dialysis in MHD patients. Patients demonstrating improved hemodynamic after dialysis exhibit relatively stable blood pressure profiles and better controls of total cholesterol and iPTH.

Key words: Maintenance hemodialysis, Thoracic impedance method, Hemodynamics