Early prediction of coma recovery after cardiac arrest with blinded pupillometry
Despite several advantages and being supported by current guidelines,5 this approach has some limitations, inherent to the different modalities employed. Among them, clinical examination lacks quantitative assessment, electrophysiological tools are not available worldwide or lack standardization (eg, EEG reactivity),7 and blood biomarkers of brain injury (eg, neuron‐specific enolase [NSE]) are limited by variable cutoffs for poor prognosis.8 Even more importantly, recent reviews identified a number of limitations of all prognostication studies, particularly the lack of blinding, which may have led to some degree of self‐fulfilling prophecy and to an overestimation of the specificity of outcome prognosticators.4
Automated infrared pupillometry provides a quantitative measure of pupil size, pupillary light reflex (PLR), and constriction velocity, and is emerging as a novel modality to evaluate brainstem function at the bedside in critically ill patients.10 Preliminary studies in comatose CA patients found that quantitative PLR performed better than standard clinical evaluation in predicting outcome.13
Here, we examined, using a blinded approach, the accuracy of quantitative PLR in predicting 1‐year neurological recovery of comatose CA patients. The predictive value of quantitative PLR was compared to that of other standard prognostic modalities, including clinical examination, EEG, and SSEP. Moreover, we explored whether quantitative PLR was correlated with serum NSE.