Emergency Ultrasound Diagnosis of Lobar Consolidation

A 69-year-old man with a medical history significant for hypertension, diabetes mellitus, and a remote cerebrovascular accident presented to the emergency department having had diarrhea and abdominal pain for one week. Upon further questioning, the patient stated that he had been having worsening dyspnea on exertion, a nonproductive cough, and subjective fevers. His vital signs were blood pressure 171/80 mm Hg, heart rate 110 beats/min, respirations 24 breaths/min, temperature 102°F, and pulse oximetry 83% while breathing room air. Laboratory analysis showed a moderate leukocytosis and mild azotemia.

An anteroposterior portable chest radiograph was obtained (Figure 1) and was suggestive of a large right-sided pleural effusion. To evaluate for a possible thoracentesis, the treating emergency physician performed a bedside thoracic ultrasound with a 5–2 MHz curvilinear transducer (SonoSite MTurbo, Bothell, WA). Evaluation of the right anterolateral lung windows demonstrated a consolidation of the right middle and lower lobes, with visible air bronchograms and no significant pleural effusion (Figure 2 and Video Clip S1). No attempt at thoracentesis was made, and instead a high-resolution computed tomography scan of the chest was obtained, which confirmed the diagnosis of right middle and lower lobe pneumonia. Intravenous antibiotics were administered and the patient was admitted to the hospital where urinalysis subsequently yielded a positive Legionella antigen test.

Figure 1.  Anteroposterior portable chest radiography reveals opacity in the right middle and lower lung fields, suggesting a right-sided pleural effusion.

Figure 2.  Sagittal ultrasound image from the right midaxillary line demonstrates a solid organ appearance to the right lung (L), with hyperechoic dynamic air bronchogram (asterisk). Note the ribs (r) and their associated shadows, the liver (labeled), and the diaphragm (d).

While chest radiography is an excellent imaging modality, it can occasionally fail to differentiate pleural effusions from pulmonary consolidations. Bedside ultrasound is a rapid, noninvasive, point-of-care imaging modality that may assist in the evaluation of patients with suspected pleural effusions.