Subcutaneous Emphysema in a Young Man

History  A healthy 19-year-old man with a prior history of mild asthma, but asymptomatic for the last eight years, had development of a mild upper respiratory tract infection one day before admission. After ingesting ten to 12 aspirin tablets during the early evening for a headache, he became nauseated and vomited several times. He next experienced acute pleuritic substernal chest pain with epigastric radiation and subsequently noted cervical, facial, and thoracic crepitation. He entered the emergency room for evaluation of his headache, moderate abdominal discomfort, and "skin bubbles."Subcutaneous crepitation was noted over his upper thorax and in his facial and cervical areas. Cardiac auscultation revealed "crunching" heart sounds. Abdominal examination demonstrated only mild epigastric tenderness on palpation. His vital signs and the remainder of his physical examination were normal. A routine complete blood cell count and levels for serum electrolytes and serum amylase were unremarkable. Roentgenograms of the chest