65-yo female with COPD presents to the ED severely distressed and dyspneic. Oxygen saturation 70%. Breathing frequency 45/min. Obstructive breath sounds with spread rhonchi. The patient is heavily dependent on accessory respiratory muscles. 120BPM. BP 100/70. Afebrile. COPD with acute exacerbation is suspected. Corticosteroids, bronchodilators and oxygen are administered. A bloodgas shows PCO2 retention and respiratory acidosis. Vitals slightly improved but oxygen saturation is not adequate. Higher levels of oxygen therapy will cause carbon dioxid narcosis. BIPAP is started with progressive improvement. Bedside ultrasound:
Left lateral thoracic- and upper abdominal view plus zoom. Significant for consolidations and hence a high suspicion of severe pneumonia/pneumosepsis. Fluids and antibiotics are administered. Bloodpanel returns showing Lactate 4,5, CRP 200 and WBC 18 with a left shift. A central venous catheter is placed.
The patient is taken to the ICU where a new bedside ultrasound is done. Consolidations are again visualized. In addition the following is seen.
What do you think? Please comment below. All intercostal spaces look the same. The pleura is statically prolapsed intercostally. My guess:the intercostal muscles have been through a marathon of strain. Currently flaccid and off-loaded by a well-deserved non-invasive ventilation. Additionally we see a flattened diaphragm which signifies severe COPD/emphysema.
Three days into treatment inflammatory parameters and oxygen saturation have been improved and NIV discontinued.
Left lateralt thoracic- and upper abdominal view. Interestingly enough the consolidation has changed. What we see now is an air bronchogram/hepatization of the lung which simply means that the lung takes on the appearance of a liver. The bronchi appear white. Causes may vary, but in short it implies lung consolidation or atelectasis. In contrast to chest x-ray, ultrasound can divided air bronchograms into either static with no movement in the bronchi or to dynamic with movement in the bronchi (see youtube). The dynamic form has a very high specificity and positiv predictive value for pneumonia. In our case the air bronchogram is static but the clinical scenario implies an infectious process.
Furthermore the intercostal space and pleura seem to have normalized.
1. The dynamic air bronchogram. A lung ultrasound sign of alveolar consolidation ruling out atelectasis. 2009. Lichtenstein D, Mezière G, Seitz J.
2. Radiopaedia.org – Air bronchogram
3. Introduction to Bedside Ultrasound: Volume 1 by Matthew Dawson och Mike Mallin (free at Itunes)