Masimo announced the findings of a study published in the Journal of Critical Carein which Dr. Tae Youn Kim and colleagues at the Dongguk University College of Medicine and Yonsei University College of Medicine in Korea evaluated the ability of two parameters provided by Masimo SedLine® brain function monitoring to predict neurological outcomes and long-term survival in post-cardiac arrest ICU patients.1 The researchers found that the combination of the two parameters, Patient State Index (PSi) and Suppression Ratio (SR) had “high predictability” for mortality 180 days after cardiac arrest. They enrolled 103 adult patients between January 2017 and August 2020 who experienced a non-traumatic out-of-hospital cardiac arrest, had been successfully resuscitated after CPR, and received targeted temperature management during their ICU stay. PSi and SR were continuously monitored using Masimo SedLine from immediately after ICU admission until 24 hours after return of spontaneous circulation (ROSC), recorded at one hour intervals. Neurological outcomes were categorized using the Pittsburgh Brain Stem Score (PBSS) and Cerebral Performance Category (CPC). Data on survival at 180 days was obtained via telephonic interviews. The researchers found that using either PSi or SR alone had “good predictability” for poor neurological outcome, and that the combination of low PSi and SR had “high predictability” for mortality 180 days after cardiac arrest. They used receiver operating characteristic (ROC) curves to determine that “a mean PSI = 14.53 and mean SR > 36.6 showed high diagnostic accuracy” as single prognostic factors for patients in their study. Furthermore, “Multimodal prediction using the mean PSi and mean SR showed the high area-under-the-curve value of 0.965 (95% confidence interval 0.909–0.991).” In the study cohort, patients with mean PSi = 14.53 and mean SR > 36.6 had “relatively higher long-term mortality rates” (69% died in the group) than those of patients with values > 14.53 and = 36.6 (11% died in the group).