Unilateral pupillary mydriasis from nebulized ipratropium bromide: A false sign of brain herniation in the intensive care unit
A 69-year-old man with a history of primary lung carcinoma and a right frontal mass was admitted to our intensive care unit (ICU) after a craniotomy for brain biopsy and tumor resection. He had left facial weakness and hemiparesis after craniotomy and was treated with corticosteroids for vasogenic edema. On ICU day 5, he was noted to have a dilated and fixed left pupil (5 vs. 3 mm on the right) without ptosis, extraocular movement impairment, or mental status change. Emergent computed tomography (CT) of the head showed no evidence of mass effect or uncal herniation. Review of medications revealed that he received ipratropium bromide nebulizer treatment (500 μg) every 4 h for respiratory distress. His anisocoria resolved within a few hours after discontinuation of ipratropium bromide treatment.