We present the case of a 17-year-old school-age patient who came to the Emergency Department due to central thoracic pain that had been evolving over the previous 24 h, accompanied by the sensation of dyspnea in the context of mild asthma.
Initially, we performed POCUS (point-of-care ultrasound) (Fig. 1), and several previous radiographs from childhood were available. The subxiphoid view showed normal cardiac contractility, normal chamber size, and no pericardial effusion. The long parasternal and apical views showed poor image quality and the presence of B lines (arrows), suggesting an air artifact. In the neck, the transverse ultrasound image showed the hyperechogenic linear line with posterior reverberation, which was consistent with air (subcutaneous emphysema).1,2
At this point, there was greater concern for a pneumomediastinum dissecting in front of the heart, causing poor ultrasound windows. Thoracic CT scan (Fig. 2) showed extensive pneumomediastinum (white arrows) and subcutaneous emphysema (black arrows) in the lower neck and chest wall. A rim of gas attenuation was observed in the bilateral pleural spaces, but there was no massive pneumothorax.
The patient progressed favorably and was discharged 72 h later.
Conflict of interestNo conflict of interest.
FundingNo funding received.
Ethical approvalEthical considerations, informed consent obtained from the patient.





