Kouw P M, Kooman J P, Cheriex E C, Olthof C G, de Vries P M, Leunissen K M
Department of Medical Physics, Free University of Amsterdam, The Netherlands.
J Am Soc Nephrol. 1993 Jul;4(1):98-104. doi: 10.1681/ASN.V4198.
Because clinical indices of hydration state are insensitive, the estimation of correct postdialysis dry weight is still major problem. Recently, some new techniques have been introduced to assess postdialysis dry weight more accurately. The plasma concentrations of the biochemical markers atrial natriuretic peptide (ANP) and cGMP are related to intravascular hydration state. The echographically measured inferior caval vein diameter (VCD) is linked to right atrial pressure and blood volume (BV). Regional noninvasive conductivity measurements provide information about regional extracellular fluid volume (EFV). In this study of postdialysis ANP and cGMP concentrations, VCD and EFV yielded postdialysis diagnoses of hydration state in 18 patients on maintenance dialysis. In order to verify the established diagnosis, hemodynamic and BV changes during dialysis were studied. In postdialysis underhydrated patients, differentiated according to VCD and EFV standards, a pronounced decrease in BV, stroke volume, and left ventricular end-diastolic diameter compared with postdialysis normohydrated patients was observed. Hemodynamic and BV changes during dialysis were identical in the groups selected according to postdialysis ANP level. Only a difference in BV decrease was demonstrated between the groups selected according to postdialysis cGMP. Predialysis and postdialysis VCD correlated well with the corresponding EFV (r = 0.7 and r = 0.8, respectively). Because VCD and EFV were related and interpretation yielded diagnoses of postdialysis hydration state that were substantiated by the finding of classical hemodynamic features of underhydration, both are an asset in the diagnosis of postdialysis dry weight. cGMP values are less informative, and ANP does not provide any information at all.
由于水化状态的临床指标不敏感，正确估计透析后干体重仍然是一个主要问题。最近，一些新技术被引入以更准确地评估透析后干体重。生化标志物心房利钠肽（ANP）和环磷酸鸟苷（cGMP）的血浆浓度与血管内水化状态有关。超声测量的下腔静脉直径（VCD）与右心房压力和血容量（BV）相关。区域无创电导率测量可提供有关区域细胞外液量（EFV）的信息。在这项关于透析后ANP和cGMP浓度的研究中，VCD和EFV对18例维持性透析患者的透析后水化状态作出了诊断。为了验证已确立的诊断，研究了透析期间的血流动力学和BV变化。在根据VCD和EFV标准区分的透析后水合不足患者中，与透析后水合正常的患者相比，观察到BV、每搏输出量和左心室舒张末期直径明显降低。根据透析后ANP水平选择的组中，透析期间的血流动力学和BV变化相同。根据透析后cGMP选择的组之间仅显示出BV降低的差异。透析前和透析后的VCD与相应的EFV相关性良好（分别为r = 0.7和r = 0.8）。由于VCD和EFV相关，并且其解释得出的透析后水化状态诊断得到了水合不足的经典血流动力学特征的证实，因此两者都是诊断透析后干体重的有用指标。cGMP值提供的信息较少，而ANP根本不提供任何信息。
