In two separate incidents, two toddlers with no previous history of respiratory ailments presented to the emergency department of a children's hospital with progressive respiratory distress. Both children had unilateral lung findings on auscultation and initial chest radiographs that were consistent with a pneumothorax. Thoracostomy and chest tube insertion were performed during initial resuscitation efforts. In both cases, subsequent radiographs revealed that the stomach was located in the left hemithorax, suggestive of a diaphragmatic hernia. Nasogastric tube insertion relieved the respiratory distress of these two children. Recognition of the "acquired" congenital diaphragmatic hernia in the setting of extreme aerophagia or mild abdominal trauma may prevent unnecessary procedures during the resuscitation of children with acute respiratory distress and unilateral lung findings.