应用生物电阻抗预测方程评价维持性血液透析患者干体质量

Assessment of dry weight among maintenance hemodialysis patients with the application of bioelectrical impedance prediction equation

目的探讨运用生物电阻抗预测方程评价维持性血液透析(maintenance hemodialysis,MHD)患者干体质量的准确性。方法使用多频生物电阻抗分析仪测定60例MHD患者50千赫下电阻抗值,结合斜率法、新三室模型预测MHD患者干体质量。经下腔静脉直径(inferior vena cavadiameter,IVCD)等综合评价,认为患者的干体质量即入选患者本次透析后体质量,可用于干体质量准确性评价。另选择性别、年龄、身高,体质量和体质量指数(BMI)相匹配个体87例,用于构建方程系数及与MHD患者人体参数比较。结果斜率法预测结果与干体质量比较:Pearson r=0.991,Bland-Altman显示各点均距零点较远,两者一致性欠佳;新三室模型预测结果与干体质量比较:Pearson r=0.993,Bland-Altman显示各点波动于差值零点附近,两者一致性较好。结论不同的生物电阻抗测量仪对所测数据存在影响,在本研究中,新三室模型所得结果能更准确的预测MHD患者干体质量。

Object To explore the accuracy of bioelectrical impedance prediction equation in the evaluation of dry weight among maintenance hemodialysis(MHD) patients.Methods Dry weight of 60 MHD patients was estimated using electrical impedance value of 50 KHz frequency measured by bioelectrical impedance analyzer,combined with slope method and new 3-compartment model.Dry weight of these participants was the post-dialysis weight,measured by inferior vena cava diameter(IVCD) method which was deemed as golden standard.Another 90 individuals with matched gender,age,height,body weight and BMI were selected to construct coefficient and compare the human body parameters with MHD patient.Results Pearson correlation coefficient between the evaluated dry weight by slope method and true dry weight was 0.991.BlandAltman plot showed these two approaches bore poor consistency and the difference between them was far from zero.Pearson correlation coefficient between assessed dry weight by new 3-compartmental model and true dry weight was 0.993.Bland-Altman plot revealed good consistency between the two methods with stable and minor diffidence as their differences fluctuated near zero.Conclusion Different bioelectrical impedance measuring instrument gives rise to the impact on measured data.In this study,the new 3-compartment model predicts the dry weight of MHD patients more accurately.