Tension pneumopericardium after cardiac surgery: a rare but lethal problem.

A 13-month-old girl who had no medical history uneventfully underwent patch closure of an atrial septal defect under mild hypothermic cardiopulmonary bypass. An immediately postoperative chest radiograph did not show any unusual findings (the Figure, A), and the process of weaning her from the ventilator was started. Just before extubation (6 hours after transfer to the intensive care unit), a sudden desaturation occurred, and a massive bloody secretion drained through the endotracheal tube. Echocardiography showed that the interventricular septal motion was slightly paradoxical, but ventricular contractility was normal. Chest radiograph revealed an unexpected massive pneumopericardium with bilateral pulmonary edema and pneumomediastinum with subcutaneous emphysema (the Figure, B). After a large amount of air was drained by mobilization of a pericardial tube, vital signs and arterial blood gas stabilized. Close observation of the patient with full sedation, diuretics, and decompression of the stomach did not detect the addi-