Nebulized ipratropium bromide in fixed dilated pupil: three cases report and review of literature

This study is to identity the clinical characteristics of mydriasis derived from nebulized ipratropium bromide in neurosurgical patients. We presented 3 patients with inhalation of ipratropium bromide associated mydriasis and reviewed the pertinent literature. Mydriasis was caused by nebulized ipratropium bromide leak from the mask into ipsilateral eye. When the medication was discontinued in the 3 patients, the pupillary abnormality was resolved in 2 patients, but 1 patient’s pupil was not recovered. Ipratropium bromide blocks muscarinic acetylcholine receptors in sphincter pupillae. It absorbs through the cornea and conjunctiva, blocking the sphincter pupillae cholinergic M receptor antagonist lead to mydriasis, if lasts for a long time it will compress anterior chamber angle, impede real water reflux, cause increased intraocular pressure, induce glaucoma and ocular pain. It should quickly identify mydriasis reason in the clinical work, avoiding unnecessary invasive operation and imaging examination, to reduce the burden of patients.