Ipratropium-bromide-induced acute anisocoria in the intensive care setting due to ill-fitting face masks.

Anisocoria, or unequal pupil size, may be an early sign of an impending neurologic emergency in any patient.1 Acute unilateral mydriasis is often suggestive of a lifethreatening condition affecting cranial nerve function, such as tumor compression, intracranial hypertension with impending uncal herniation, expanding intracranial aneurysm, or hemorrhage. Benign mydriasis can be due to prior trauma, medication effects, and congenital abnormalities. Determining the cause of anisocoria can be challenging in critical care settings because patients often are sedated, paralyzed, intubated, or have a baseline altered mental status that makes full neurologic examination difficult. The workup of acute anisocoria frequently involves costly and/or invasive procedures, including computed tomography (CT), magnetic resonance imaging, electroencephalography, lumbar puncture, and neurologic consultations before ruling out the most serious causes. We report 2 cases of anisocoria in elderly intensive care unit (ICU) patients, that were probably due to inadvertent ocular exposure to ipratropium caused by ill-fitting face masks. The unilateral mydriasis resolved spontaneously after life-threatening causes were excluded, and when the masks were removed or better fitted. Cases of ipratropiumbromide-induced anisocoria have rarely been reported, and we include a review of the English-language literature.1–12 Ipratropium bromide-induced anisocoria may be seen more frequently with the increased use of aerosolized anticholinergics and noninvasive positive-pressure ventilation in the management of respiratory insufficiency. Case Report 1