Noninvasive regional cerebral oxygen saturation for neurological prognostication of patients with out-of-hospital cardiac arrest: a prospective multicenter observational study

Abstract

Aim: To investigate the association between regional brain oxygen saturation (rSO2) at hospital arrival and neurological outcomes at 90 days in patients with out-of-hospital cardiac arrest (OHCA).

Methods: The Japan-Prediction of neurological Outcomes in patients post cardiac arrest (J-POP) registry is a prospective, multicenter, cohort study to test whether rSO2 predicts neurological outcomes after OHCA. We measured rSO2 in OHCA patients immediately after hospital arrival using a near-infrared spectrometer placed on the forehead with non-blinded fashion. The primary endpoint was "neurological outcomes" at 90 days after OHCA.

Results: EMS providers are not permitted to terminate CPR in the field in Japan, and so most patients with OHCA who are treated by EMS personnel are transported to emergency hospitals. Among 1017 OHCA patients, 672 patients including 52 comatose patients with pulses detectable (8%) and 620 cardiac arrest patients (92%) at hospital arrival were enrolled prospectively and consecutively. Twenty-nine patients with good neurological outcome had a significantly higher value of rSO2 at hospital arrival than 643 patients with poor neurological outcome (mean [±SD] 55.6±20.8% vs. 19.7±11.0%, p<0.001). Receiver operating curve analysis indicated an optimal rSO2 cutoff point of >42% for predicting good neurological outcome, with sensitivity 0.79 (95% confidence interval [CI], 0.60-0.92), specificity 0.95 (95% CI, 0.93-0.96), positive predictive value, 0.41 (95% CI, 0.28-0.55), negative predictive value, 0.99 (95% CI, 0.98-1.00), and area under the curve 0.90 (95% CI, 0.88-0.92).

Conclusion: The rSO2 at hospital arrival can predict good neurological outcome at 90 days after OHCA.

Keywords: Cardiac arrest; Cardiopulmonary resuscitation; Emergency department; Predictors; Regional brain oxygen saturation.