Air Under the Diaphragm

A 75-year-old man was brought to the emergency department with fever, cough, and abdominal pain of 2 days’ duration. The pain was most severe in the epigastric and umbilical regions. The patient’s history included type 2 diabetes mellitus, hypertension, and hypercholesterolemia. He had smoked cigarettes for 40 years and recently lost 50 lb. The patient was tachypneic and diaphoretic. Blood pressure was 80/40 mm Hg; pulse rate, 136 beats per minute; and respiration rate, 30 breaths per minute. The cardiac and lung examinations were unremarkable. Bowel sounds were absent; rebound tenderness was present in the abdomen. A chest film revealed air under the right hemidiaphragm, which indicated perforation of a visceral organ. Drs Sonia Arunabh and K. Rauhila of Flushing, NY, comment that an upright chest film is one of the most sensitive methods of detecting air in the abdominal cavity. In a normal chest film, the liver occupies the area under the right diaphragm; thus, no air is seen in that area. Air under the right hemidiaphragm is a major diagnostic clue; this finding usually indicates a rupture of a hollow viscus organ (eg, a gastric, appendicular, or diverticular perforation). Air under the diaphragm may also be seen in patients who have had abdominal surgery and in those who are undergoing peritoneal dialysis. This patient was given intravenous fluids, and a broad-spectrum antibiotic was prescribed. A ruptured duodenal ulcer was found during laparotomy. The patient’s recovery was uneventful.