Assessment of Fluid Status in Chronic Hemodialysis Patients: Role of the Doppler Echocardiography and Atrial Naturetic Peptide

The evaluation of fluid status is generally approached from clinical observation of body weight changes, congestion, edema, blood pressure and chest X-ray. However, evaluation on clinical grounds alone is not accurate enough in HD patients; moreover, no single method has emerged as a gold standard to assess the fluid status in chronic hemodialysis patients. The aim of this study was to assess the fluid status among chronic hemodialysis patients using Doppler echocardiographic parameters including inferior vena cava diameter (IVCD) and its correlation to plasma atrial naturetic peptide (ANP).Patients and Sixty subjects were included in this study, 40 patients on chronic hemodialysis and 20 subjects as control group. The subjects of this study were classified into three groups; group 1, 20 normotensive patients who were on hemodialysis for at least six months; group 2, 20 hypertensive patients who were on hemodialysis for at least six months; and group 3, 20 healthy subjects without history of cardiac disease (as a control group). The IVCD was measured in all groups by ultrasound and Doppler echocardiography to estimate the pulmonary flow and post dialysis plasma atrial naturetic peptide (ANP). A significant difference in the IVCD 2 hours after hemodialysis was seen between the hypertensive and the normotensive groups. In addition, we found that a significant difference in the peak pulmonary vein systolic velocity between the three groups. There was a significant negative correlation between the peak pulmonary systolic velocity to peak pulmonary diastolic and IVCD. In addition, there was a significant difference between mean ANP level among the three studied groups and the ANP was significantly correlated with IVCD in corresponding groups respectively. The current study showed an increase in the IVCD and ANP as well as an increase S/D ratio in hemodialysis patients with hypertension than normotensive hemodialysis cases and the controls. Thus we emphasize the importance of assessment of fluid status using Doppler echocardiographic parameters as pulmonary venous flow using S/D ratio.