Study the Role of Lung Ultrasound in Assessment of Subclinical Fluid Overload in Maintenance Hemodialysis Patients with Intra-Dialytic Hypertension

Objectives: To elucidate the role of lung ultrasound in assessment of subclinical fluid overload in hemodialysis (HD) patients. Background: Volume overload has a significant role in HD patients with difficult blood pressure control. The clinical evaluation of fluid status is challenging and has poor diagnostic accuracy. Extravascular lung water (ELW) represents an important element of body fluid volume. Lung ultrasound (LUS) is increasingly used for ELW assessment through the analysis of B-lines artifacts. Methods: Eighty-eight HD patients were followed up prospectively. Patients were divided into 3 groups according to the changes of systolic blood pressure (SBP) during HD sessions. Group (1): patients with intra-dialytic hypertension (n = 12), group (2): patients with intra-dialytic hypotension (n = 28) and group (3): patients with no significant blood pressure variabilities (n = 48). Numbers of B-lines were measured by LUS and IVC diameters were measured pre and post-dialysis. In addition, Endothelin-1 (ET-1) and other routine laboratory tests were done. Results: There were significant increases in the number of B-lines and IVC diameter pre and post-dialysis in group (1) compared to the other two groups. There was significant decrease in post dialysis IVC diameter but not the number of B-lines in group (2) compared with the other two groups. ET-1 level was significantly increased in group 1 compared to the other two groups. There was a statistically significant positive correlation between the pre-dialysis number of B-lines and ET-1. Conclusion: Lung ultrasound can be considered a sensitive and specific modality for volume assessment in HD patients especially with intra-dialytic hypertension. We recommend serial LUS as a part of management in this group of patients.