Pupillary Light Reflex Is Not Abolished by Epinephrine and Atropine Given During Advanced Cardiac Life Support in Patients Who Achieve Return of Spontaneous Circulation

Abstract

Introduction: Absence of pupillary light reflex (PLR) is a well-studied indicator of poor neurologic recovery after cardiac arrest. Interpretation of absent PLR is difficult in patients with hypothermia or hypotension, or who have electrolyte or acid-base disturbances. Additionally, many studies exclude patients who receive epinephrine or atropine from their analysis on the basis that these drugs are thought to abolish the PLR. This observational cohort study assessed for presence or absence of PLR in in-hospital cardiac arrest patients who received epinephrine with or without atropine during advanced cardiac life support and achieved return of spontaneous circulation (ROSC). Methods: Pupil size and reactivity were assessed in adult patients who had an in-hospital cardiac arrest, received epinephrine with or without atropine, and achieved ROSC. Measurements were taken using a NeurOptics NPi-200 infrared pupillometer. Results: Forty patients had pupillometry performed within 1 hour (median: 6 minutes) after ROSC. Of these only 1 (2.5%) patient had nonreactive pupils at first measurement after ROSC. The remaining 39 (97.5%) had reactive pupils. Of the 19 patients who had pupils checked within 3 minutes of ROSC, 100% had reactive pupils. Degree of pupil responsiveness was not correlated with cumulative dose of epinephrine. Ten patients received atropine in addition to epinephrine, including the sole patient with nonreactive pupils. The remaining 9 (90%) had reactive pupils. Conclusion: Epinephrine and atropine do not abolish the PLR in patients who achieve ROSC after in-hospital cardiac arrest. Lack of pupillary response in the post-arrest patient should not be attributed to these drugs.