We report the case of a 12-day-old newborn affected by coarctation of the aorta and intraventricular defect who underwent coarctectomy and pulmonary artery banding. On post-operative day 7, the patient suffered from pulseless electric activity due to tension pneumothorax. Point-of-care ultrasound was performed during cardiopulmonary resuscitation in an attempt to diagnose pneumothorax. The diagnosis was made without delaying or interrupting chest compressions, and the pneumothorax was promptly treated.