Left mainstem bronchus intubation.

We report a case of a 78-year-old woman, previously in good health, who was endotracheally intubated and brought to the emergency department following sudden cardiac arrest. Physical examination revealed absent breath sounds over the right hemithorax, and a portable chest radiograph demonstrated left mainstem bronchus intubation. Although right mainstem bronchus intubation is a common complication of endotracheal intubation, left mainstem bronchus intubation is rare.