Unilateral pupillary mydriasis from nebulized ipratropium bromide: A false sign of brain herniation in the intensive care unit
A 32-year-old, previously healthy woman presented with headache, drowsiness, global aphasia, and right hemiparesis from a left frontal intracerebral hemorrhage. Moyamoya disease was diagnosed and she underwent urgent craniotomy for hematoma evacuation. Postprocedurally, her mental status improved with a persistent right facial droop and dense right hemiparesis. On ICU day 4, she was noted to have an isolated dilated and fixed right pupil (9 vs. 3 mm on the left). An urgent CT scan showed no evidence of mass effect or brain herniation. The patient had received nebulized bromide ipratropium every 4 h over the previous few days. The anisocoria resolved within 24 h of ipratropium bromide discontinuation.