Role of Lung Ultrasound in the Assessment of Hydration Status of Chronic Haemodialysis Patients

Background: Fluid overload is frequent in Haemodialysis (HD) and is one of the major factors of cardiovascular morbidity and mortality for chronic HD patients. The main challenge with chronic haemodialysis patients is indeed the maintenance of a normal extracellular volume through dry weight determination. Our study aimed at assessing the role of lung ultrasound in the detection of B-lines for the determination of hydration status in chronic HD patients. Methods: We conducted a cross-sectional study including 31 patients undergoing chronic HD treatment for at least 3 months, in the Yaounde University Teaching Hospital dialysis unit. Lung ultrasonography and clinical examinations were performed immediately before dialysis, and 30 minutes after dialysis. Differences between clinical and ultrasound variables before and after dialysis were measured to assess the effects of dialysis. Association between categorical variables was assessed with the Chi-squared test or Fischer test, and Rho’s Spearman coefficient for quantitative variables. Results: There was a reduction in the median of B-lines score after dialysis [12 (7 - 26) versus 8 (5 - 13)], clinical score [2 (1 - 3) versus 0 (-1 - 2)], mean of systolic blood pressure (164.74 ± 26.50 versus 158.48 ± 27.89), frequency of dyspnoea in patients (32.3% versus 6.5%);and raising of the frequency of cramps in patients (0% versus 19.4%) and all statistically significant (p ≤ 0.031). B-lines score before and after dialysis was associated with dyspnoea and raised jugular venous pressure (p Conclusion: Lung ultrasound for the detection of B-lines reflects the variation of extracellular volume during dialysis and can even capture pulmonary oedema at a pre-clinical stage. It is then a reliable and sensible method for assessing extravascular lung water and thus hydration status of haemodialysis patients. It could constitute a better alternative for an objective and accurate definition of dry weight, specifically in the African and Cameroonian context, with its assets being low cost, availability, and easiness to perform in a large population of HD patients. We, therefore, recommend further multicentric studies in order to design a standardized protocol of ultrasound follow-up for all chronic HD patients’ hydration status assessments.

The Observation on Risk of Ventilator Failure Weaning by Ultrasound bedside Monitoring of Inferior Vena Cava and Lung B Line

Objective: This study was designed to investigate risk of ventilator weaning by ultrasound bedside monitoring of the width of inferior vena cava (IVC) and the number of lung B-lines (B-lines). Methods: This study was conducted on 106 patients from January 2019 to January 2020 who had mechanical ventilation for more than 48 hours in an emergency care unit. They were clinically stable and had the criteria for weaning from the ventilator. Before Spontaneous Breathing Test (SBT) and 30 min or 120 min after SBT, the width of IVC and the number of B-lines in patients were monitored via bedside ultrasound. There were 87 cases of successful weaning as a control group and 19 cases of ventilator failure weaning as a study group. Changes of the width of IVC and the number of B-lines were compared in the different stages of SBT. Results: A total of 106 patients were included in this study. There were 87 cases of ventilator successful weaning and 19 cases failure weaning. The weaning success rate was 82.08%. The width of IVC and the number of B-lines in the study group were higher than those in the control group in same stage of SBT, the difference was statistically significant (P < 0.05), and which increased significantly with time. There was no significant difference in the width of IVC and the number of B-lines on the different stage of SBT in the control group (P > 0.05), and significant difference in the study group. Conclusion: The width of IVC and the number of B-lines monitored by bedside ultrasound can assess the risk of ventilator weaning, it may be caused by cardiopulmonary interaction.

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.

Single Wire Electrical System

The purpose of this article is to remind of the past and present problems of creating single wire electrical systems. This article presents a new one wire electrical transmission system named B-Line which uses one line only and does not use ground as a second line. The proposed method is to work on all frequencies and on all communication systems including DC systems. It also proposes to work on the concept of the single-pole signal source and single-pole signal load. It illustrates the possibility of cutting the cost of electrical lines and several other advantages in the fields of high frequency communication lines and antennas.