Quantitative Lung Ultrasonography for the Nephrologist: Applications in Dialysis and Heart Failure

Abstract

Volume overload and its attendant increase in acute care utilization and cardiovascular morbidity and mortality represents a critical challenge for the practicing nephrologist. This is particularly true among patients with ESKD on HD where pre-dialysis volume overload and intradialytic and postdialytic hypovolemia account for almost a third of all cost for the Medicare dialysis benefit. Quantitative lung ultrasound is a tool for assessing the extent of extravascular lung water which outperforms physical exam and plain chest radiography. B-lines are vertical hyperechoic artifacts present in patients with increased extravascular lung water. B-lines have been shown to decrease dynamically during the hemodialysis treatment in proportion to ultrafiltration volume. Among patients with chronic heart failure, titration of diuretics based on the extent of pulmonary congestion noted on lung ultrasonography has been shown to decrease recurrent acute care utilization. Early data from randomized-controlled trials of lung ultrasound-guided ultrafiltration therapy among patients with ESKD on HD have shown promise for potential reduction in recurrent episodes of decompensated heart failure and cardiovascular events. Ultimately lung ultrasound may predict those who are ultrafiltration tolerant and could be used to decreased acute care utilization and thus cost in this population.

Diagnosis of Fluid Overload: From Conventional to Contemporary Concepts

“…6). Prognostic significance of lung ultrasound-detected pulmonary congestion has been well established in multiple clinical settings including HF, hemodialysis, and critical illness [108]. For example, in a cohort of 185 HF patients who underwent lung POCUS in the outpatient clinic, those who had ≥3 Blines on an 8-zone scanning protocol had 4-fold higher risk of the primary outcome, i.e., a composite of HF hospitalization or all-cause mortality (adjusted HR 4.08, p < 0.001) [109].…”

PoCUS in nephrology: a new tool to improve our diagnostic skills

“…US reflection generates hyperechoic reverberation artifacts between thickened septa and the overlying pleura, which are defined as B-lines or comet tails (Fig. 4C ) [ 46 ]. It is generally considered that the appearance of three or more comets is relevant.…”

“…Moreover, pleural effusion can be identified by black images and the absence of pleural sliding (Fig. 4D ) [ 46 ].…”

Point of Care Ultrasound in Cirrhosis-Associated Acute Kidney Injury: Beyond Inferior Vena Cava

“…Lung ultrasound is an easy-to-learn skill that allows rapid detection of extravascular lung water often before the onset of symptoms. Its diagnostic superiority compared to chest auscultation is welldocumented, particularly in patients with heart failure and end-stage kidney disease [16]. In the liver intensive care units, lung POCUS is often used to adjust ventilator settings, determine readiness for extubation, guide ultrafiltration as well as screen for procedural complications such as pneumothorax after central venous catheter placement [17].…”