Unilateral pupillary mydriasis from nebulized ipratropium bromide: A false sign of brain herniation in the intensive care unit

Priyanka Chaudhry, Deborah I Friedman, Wengui Yu

Research output: Contribution to journalArticle

7 Scopus citations


Although there are many causes of anisocoria in the intensive care setting, the development of unilateral mydriasis in patients with intracranial hemorrhage or tumor is a neurological emergency, as it may herald the onset of uncal herniation. We describe two patients with a hemiparesis from neurosurgical disorder who subsequently developed a fixed and dilated pupil. The pupillary abnormality was caused by nebulized ipratropium bromide in both cases, and resolved when the medication was discontinued. Nebulized ipratropium may leak from the mask into ipsilateral eye and cause mydriasis in patients with facial weakness. This benign cause of anisocoria in the intensive care setting is distinguished from uncal herniation by the laterality of neurologic findings, and lack of mental status change, ptosis, and extraocular movement impairment.

Original languageEnglish (US)
Pages (from-to)176-177
Number of pages2
JournalIndian Journal of Critical Care Medicine
Issue number3
Publication statusPublished - 2014



  • Anisocoria
  • hemiparesis
  • ipratropium bromide
  • mydriasis
  • uncal herniation

ASJC Scopus subject areas

  • Critical Care and Intensive Care Medicine

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