Pseudo-Pneumothorax: Look Before You Leap!

To the Editor: A 58-yr-old man underwent surgery for intracranial aneurysm. He was breathing normally on room air through a tracheostomy tube and maintained hemoglobin oxygen saturation between 96%–99%. Chest radiograph obtained because of persistent cough revealed features suggestive of pneumothorax (Fig. 1). Immediate placement of a chest tube was considered to prevent further complications but, in view of stable respiratory parameters and no clinical evidence of respiratory distress, a second radiograph was obtained and no evidence of pneumothorax was seen. (Fig. 2).Figure 1.: Bed sheet fold mimicking pneumothorax.Figure 2.: Repeat chest radiograph showing normal lung fields.Evidence of pneumothorax on chest radiograph without accompanying major respiratory signs is rare. This kind of pseudo-pneumothorax though unusual, has been previously described.1–3 Various artifacts including skin fold, shirt fold, and medial border of scapula1–3 are known to mimic pneumothorax. Though detection of lung markings in the periphery rules out pneumothorax, this is not always possible. On close observation, bed sheet artifact seen in our patient presented as broad radio-opaque curvilinear line whereas pneumothorax can be identified by a sharp thin line. It is therefore essential to correlate radiological evidence with clinical findings before proceeding to thoracostomy. Further, though chest radiograph still remains a valuable tool for diagnosis of pneumothorax, computed tomography or chest ultrasound can be used to confirm the diagnosis. Kamath Sriganesh, MD, DNB [email protected] Balethbail Suparna, MD, DNB Parthasarathi Gayatri, MD, PDCC, FRCA Department of Anesthesia Sree Chitra Tirunal Institute for Medical Sciences and Technology Trivandrum, Kerala, India