Enrolled patients had a screening history and physical examination performed at the time of triage to determine eligibility into the study. After informed consent was obtained, enrolled patients had clinical exam findings documented on a standardized form and underwent point-of-care lung ultrasound examination. An ultrasound machine with a linear array transducer at 7.5 to 10 MHz (Sonosite Micromaxx, Bothell, WA, USA) was used to image the lungs in perpendicular planes (transverse, parasagittal, and coronal) in the midclavicular line anteriorly and posteriorly on the chest and the midaxillary line from the axillae to diaphragm (Figure 4 ).