Lung ultrasound in the ICU: From diagnostic instrument to respiratory monitoring tool

Imaging has greatly contributed to the understanding of lung disease in the critically ill and currently serves as a tool to diagnose lung pathology, monitor its course, and guide clinical management. Lung ultrasound is a realtime imaging modality that is simple, non-invasive, potentially ubiquitous, and free of ionizing radiation. Its increasing popularity and supporting research data substantiate its role as an emerging technique for bedside chest imaging in critical care. Furthermore, the International Consensus Conference on Lung ultrasound (ICC-LUS) promoted by the World Interactive Network Focused on Critical UltraSound (WINFOCUS) recently standardized the nomenclature and technique for lung ultrasound, and provided recommendations supporting its use in clinical practice. While the utility of lung ultrasound in the emergency setting is unquestioned, its potential role in the more complex and resource-rich intensive care environment is still under investigation. The purpose of this paper was to describe current and potential uses of lung ultrasound in the specific setting of adult intensive care, with an emphasis on respiratory monitoring, and to provide a framework for the practical application of this tool at the bedside.