Bioimpedance analysis on evaluating fluid distribution and adjusting dry weight in patients of maintenance hemodialysis / 中华肾脏病杂志

ABSTRACT

Objective To evaluate fluid distribution in patients on maintenance hemodialysis (HD) by bioimpedance analysis and on the effect of adjusting the dry weight in hemodialysis patients.Methods Forty maintenance HD patients from the dialysis center of the Second Affiliated Hospital of Dalian Medical University were enrolled as study group.One hundred and two individuals who were tested of physical examination in the same hospital were enrolled as the control group.Sex and age of the two groups were recorded.Body weight,body high,blood pressure,bioimpedance of HD patients (pre-dialysis and post-dialysis) and controls were measured.Bioimpedance was measured by multifrequency segmental bioimpedance analysis,including right arm (RA) bioimpedance,trunk (TR) bioimpedance and right leg (RL) bioimpedance.Bioimpedance ratio (BIR) of three parts was calculated as of 100kHz and 20kHz including RA-BIR,TR-BIR and RL-BIR.Then eight HD patients who had high RA-BIA or TR-BIA according to the reference range which were obtained from 102 controls were chosen for dry weight adjustment.Post-dialysis body weight,blood pressure,and bioimpedance of the eight HD patients were measured again after adjusting the dry weight.Results (1) BIR of three parts in pre-dialysis HD patients were all significantly higher than that in the control group (P ＜ 0.05).BIR of three parts of the post-dialysis HD patients were still higher than that of the control group,but RL-BIR was not significantly (P ＞ 0.05).BIR of three parts of the post-dialysis HD patients were lower than BIR of three parts of the pre-dialysis HD patients,and there was significant different (P ＜ 0.05) with RA-BIR and RL-BIR.(2) After adjusting the dry weight,BIR of three parts of the post-dialysis HID patients were still higher than that of the control group,but none of them was significantly (P ＞0.05).BIR of three parts of the HD patients after adjusting the dry weight were lower than BIR of three parts of the HD patients before adjusting the dry weight,but there was no significant different with TR-BIR(P ＞ 0.05).After adjusting the dry weight,systolic blood pressure of the post-dialysis HD patients were significantly decrease[(150.00 ± 29.28) vs (140.63± 20.78) mm Hg,P＜ 0.05].Conclusions Bioimpedance analysis may be an effective method for adjusting dry weight in hemodialysis patients,and the bioimpedance of arms is the most effective method.The bioimpedance reference range of hemodialysis patients can be according to the reference range of normal individuals.