Abstract 48: A Multicenter Prospective Cohort Study on a Novel Neurological Prognostic Index, Regional Brain Oxygen Saturation, in Patients with Out-of-Hospital Cardiac Arrest

Abstract

BACKGROUNDS: A reliable and readily available neurological prognostic index for the cerebral resuscitation of out-of-hospital cardiac arrest (OHCA) patients (pts) is required. We have previously reported in a single center cohort study of OHCA pts that regional brain oxygen saturation (rSO 2 ) measured on hospital arrival may help predict neurological outcomes. OBJECTIVE: To compare the power of rSO 2 and conventional indexes−lactate, base excess (BE), and ammonia (NH 3 )−measured on hospital arrival to prognose neurological outcomes at 30 days after cardiac arrest that are assessed according to the cerebral performance category (CPC) criteria in a multicenter prospective cohort study. METHODS: The database of the J-POP registry (conducted at 14 tertiary emergency hospitals in Japan) has prospectively enrolled 764 OHCA pts. Of these pts, 596 (77.5%) who were examined for rSO 2 , lactate, BE, and NH 3 were analyzed in the present study. The exclusion criteria included 1) trauma, 2) accidental hypothermia, 3) age under 18, 4) do not attempt resuscitation order, 5) Glasgow Coma Scale > 8 on hospital arrival, and 6) missing data. Immediately after hospital arrival, rSO 2 was measured using a near-infrared spectroscopy device (INVOS; Covidien, USA) placed on the forehead, along with the measurement of lactate, BE, and NH 3 . Regardless of the rSO 2 readings, all pts received the best available therapy. RESULTS: Among 596 OHCA pts, 31 (5.2%) had good neurological outcome. The areas under the curve (AUCs) for the prognostic indexes-rSO 2 , lactate, BE, and NH 3 −were 0.912, 0.794, 0.773 and 0.853, respectively (Table). The AUC was significantly greater for rSO 2 than for lactate ( p = 0.0001) or BE ( p = 0.0057) and tended to be greater for NH 3 ( p = 0.0844). CONCLUSIONS: Compared with the conventional neurological prognostic indexes, rSO 2 may be more reliable for neurological prognostication based on its specificity, positive predictive value, and AUC.