We describe the clinical and radiographic features of four premature infants with acute iatrogenic tracheobronchial perforation by endotracheal tube (ETT) placement. One tube penetrated posteriorly into the esophagus, one directly through the carina; one perforated the right main bronchus posteriorly; and one breached the site of a recently repaired tracheoesophageal fistula. In only one infant was the intubation procedure clinically recognized to be traumatic. Radiographs obtained for tube placement demonstrated inferior malposition of the ETT in all four babies, decreased pulmonary aeration in three of four, acute retrocardiac infraazygos pneumomediastinum in three of four, and acute pleural effusion in one of four. Two infants developed progressive air leak and died in spite of drainage with multiple chest tubes; two survived and did well with conservative management. An additional eight cases have been previously reported, with an overall mortality of 58%. Prompt recognition of acute airway perforation can be lifesaving. Unexpected respiratory distress after intubation associated with acute infraazygos pneumomediastinum strongly suggests this entity.