The management of complex fluid and electrolyte disorders is central to the practice of nephrologists. The sensitivity of physical examination alone to determine fluid status is limited, precluding accurate clinical decision making. Point-of-care ultrasonography (POCUS) is emerging as a valuable, noninvasive, bedside diagnostic tool for objective evaluation of physiologic and hemodynamic parameters related to fluid status, tolerance, and responsiveness. Rapid bedside sonographic evaluation can obtain qualitative data on cardiac function and quantitative data on pulmonary congestion. Advanced POCUS, including goal-directed Doppler echocardiography, provides additional quantitative information, including flow velocities and pressures across the cardiac structures. Recently, abnormal Doppler flow patterns in abdominal organs secondary to increased right atrial pressure have been linked to congestive organ damage, adding another component to the hemodynamic assessment. Integrating POCUS findings with clinical and laboratory data can further elucidate a patient’s hemodynamic status. This drives decisions regarding crystalloid administration or, conversely, diuresis or ultrafiltration and allows tailored therapy for individual patients. In this article, we provide an overview of the focused assessment of cardiovascular function and pulmonary and venous congestion using POCUS and review relevant literature.

Point-of-care ultrasonography (POCUS) has evolved as a valuable adjunct to physical examination in the recent past and various medical specialties have embraced it. However, POCUS training and scope of practice remain relatively undefined in nephrology. The utility of diagnostic POCUS beyond kidney and vascular access is under-recognized. Assessment of fluid status is a frequent dilemma faced by nephrologists in day-to-day practice where multiorgan POCUS can enhance the sensitivity of conventional physical examination. POCUS also reduces fragmentation of care, facilitates timely diagnosis, and expedites management. Although the need for further imaging studies is obviated in selected patients, POCUS is not meant to serve as an alternative to consultative imaging. In addition, the utility of POCUS depends on the skills and experience of the operator, which in turn depend on the quality of training. In this review, we discuss the rationale behind nephrologists performing POCUS, discuss patient examples to illustrate the basic principles of focused ultrasonography, and share our experience-based opinion about developing a POCUS training program at the institutional level.

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 predialysis 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 that 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 on the basis of 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 decrease acute care utilization and, thus, cost in this population.