Early Absent Pupillary Light Reflexes After Cardiac Arrest in Patients Treated with Therapeutic Hypothermia

Abstract

Loss of pupillary light reactivity is one recognized indicator of poor prognosis after cardiopulmonary resuscitation (CPR). However, drug overdose, low cardiac output, and/or resuscitation drugs can lead to impaired pupillary light reflex. To investigate pupillary light reflex status before therapeutic hypothermia (TH) in relation to neurological outcome, we retrospectively reviewed the data of a prospectively implemented TH protocol in patients with cardiac arrest (CA) at Mayo Clinic in Jacksonville, Florida (January 2006-January 2012), and Mayo Clinic in Scottsdale, Arizona (August 2010-March 2014). During this period, all CA patients who underwent hypothermia were included. These patients were selected from an institutional database and hypothermia data set. The Cerebral Performance Category (CPC) at time of discharge was our primary outcome measure. A CPC of 1 to 2 was defined as good outcome and a CPC from 3 to 5 was defined as poor outcome. We identified 99 patients who had CA treated with TH. Twenty-nine patients (29%) had pupils that were nonreactive to light on admission examination before TH, eight of whom later had return of pupil reactivity by day 3. Two of these 29 patients (6.9%) had good outcome, compared to 24 of 70 patients (34.3%) with pupils that were reactive to light (p = 0.005). Both of these patients had CA after illicit drug overdose. Early nonreactive pupils occurred in almost a third of patients after CPR and before TH in our patient population. Recovery of pupillary light reactivity is possible, and in a small minority of those cases (particularly when CA is preceded by the use of illicit drugs), a good outcome can be achieved.

Prediction of poor neurological outcome in comatose survivors of cardiac arrest: a systematic review

“…2). However, in two small studies, FPR of this sign was 50% [62] at 24-48 h and 25% at 24-72 h [94]. In a multicentre study on 201 patients [95], one false-positive result was observed (FPR 2.6%).…”

“…This was documented from the very early phase (6-12 h) up to a median of 5 days after ROSC (Table 17). However, two studies reported a false positive rate of 50% [62] and 75% [94] for SSEP. In both of these studies, only a few patients were assessed with SSEP, which may have amplified the observed false positive rate.…”

Eyeing up the Future of the Pupillary Light Reflex in Neurodiagnostics

“…Pupil function abnormalities have been reported for a wide range of disorders, including alcoholism [ 49 , 50 ], mental health disorders such as seasonal affective disorders [ 51 ], schizophrenia [ 52 ] and generalised anxiety disorder [ 53 ], Alzheimer’s [ 54 , 55 , 56 ] and Parkinson’s [ 57 , 58 , 59 , 60 ] diseases, autism spectrum disorders [ 61 , 62 ], as well as glaucoma [ 14 , 63 , 64 , 65 ] and autonomic neuropathies associated with diabetes [ 66 , 67 , 68 , 69 , 70 ]. Additionally, pupillometry has been applied to other clinical fields, such as monitoring of central states in anaesthesiology and analgesia, as well as monitoring and prognosis following head injuries, cardiac arrest and drug overdose [ 71 ].…”

Pupil Reactivity in Refractory Out-ofHospital Cardiac Arrest Treated by ExtraCorporeal Cardiopulmonary Resuscitation

“…The Glasgow coma scale motor score showed a strong predictive value for a poor outcome in non-sedated patients ( 20 ), but its diagnostic value has never been assessed in the early phase of CA ( 21 – 26 ). Loss of pupillary light reactivity is a recognised indicator of poor prognosis during and after cardiopulmonary resuscitation, even though it can be impaired in mild hypothermia, low cardiac output and modified by resuscitation drugs ( 21 ). Despite a high specificity for predicting a poor neurological outcome, its sensitivity is low ( 27 – 29 ).…”