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.

Point of care ultrasonography in onco-nephrology:A stride toward better physical examination

Onco-Nephrology is an emerging subspecialty of Nephrology that focuses on a broad spectrum of renal disorders that can arise in patients with cancer.It encompasses acute kidney injury(AKI),complex fluid,electrolyte,and acid-base disorders,as well as chronic kidney disease caused or exacerbated by cancer and/or its treatment.In many such scenarios including AKI and hyponatremia,objective evaluation of hemodynamics is vital for appropriate management.Point of care ultrasonography(POCUS)is a limited ultrasound exam performed at the bedside and interpreted by the treating physician intended to answer focused clinical questions and guide therapy.Compared to conventional physical examination,POCUS offers substantially higher diagnostic accuracy for various structural and hemodynamic derangements.In this narrative review,we provide an overview of the utility of POCUS enhanced physical examination for the Onconephrologist supported by the current evidence and our experience-based opinion.

Rapid Multi-Wavelength Optical Assessment of Circulating Blood Volume Without a Priori Data

The measurement of circulating blood volume （CBV） is crucial in various medical conditions including surgery, iatrogenic problems, rapid fluid administration, transfusion of red blood ceils, or trauma with extensive blood loss including battlefield injuries and other emergencies. Currently, available commercial techniques are invasive and time-consuming for trauma situations. Recently, we have proposed high-speed multi-wavelength photoacoustic/photothermal （PA/PT） flow cytometry for in vivo CBV assessment with multiple dyes as PA contrast agents （labels）. As the first step, we have characterized the capability of this technique to monitor the clearance of three dyes （indocyanine green, methylene blue, and trypan blue） in an animal model. However, there are strong demands on improvements in PA/PT flow cytometry. As additional verification of our proof-of-concept of this technique, we performed optical photometric CBV measurements in vitro. Three label dyes--methylene blue, crystal violet simultaneous photometric determination of the and, partially, brilliant green--were selected for components of their two-dye mixtures in the circulating blood in vitro without any extra data （like hemoglobin absorption） known a priori. The tests of single dyes and their mixtures in a flow system simulating a blood transfusion system showed a negligible difference between the sensitivities of the determination of these dyes under batch and flow conditions. For individual dyes, the limits of detection of 3×10-6M-3×10-5M in blood were achieved, which provided their continuous determination at a level of 10-SM for the CBV assessment without a priori data on the matrix. The CBV assessment with errors no higher than 4% were obtained, and the possibility to apply the developed procedure for optical photometric （flow cytometry） with laser sources was shown.