Abstract 12833: Can We Predict the Probability of ROSC by the Change in Cerebral rSO 2 Value?

Abstract

Introduction: There is no consensus on how long we should continue cardiopulmonary resuscitation (CPR). When determining this, it is important to assess the probability of return of spontaneous circulation (ROSC). We have been evaluating the usefulness of regional cerebral oxygen saturation (rSO 2 ) during resuscitation since 2007. At the 2014 AHA congress, we reported that the probability of ROSC would be low if the rSO 2 was less than 55%. In the present study, we focused on the relation between the rate of rSO 2 increase and the occurrence of ROSC from the time of hospital arrival. Methods: This was a retrospective study of out-of-hospital cardiac arrest (OHCA) patients with successful measurement of rSO 2 from December 2012 to December 2015. During CPR, rSO 2 was recorded continuously from the forehead of the patients by a TOS-OR (TOSTEC, Japan). CPR for patients with OHCA was performed according to the 2010 JRC guidelines. Results: Ninety patients with OHCA (59 men, 31 women; mean age 74.8 years) were included in this study, of whom 35 had ROSC. The baseline value of rSO 2 was determined as the mean value of the initial 1 minute of rSO 2 . The rate of change in rSO 2 was calculated as the ratio of the maximum rSO 2 value at 4, 8, 12, 16, and 20 minutes to the baseline value. Receiver operating characteristic curve analysis showed that the area under the curve was 0.72 with the cut-off value set at 14.5%. The specificity and sensitivity of ROSC were 68.6% and 68.6%, respectively. Although this cut-off value is not a criterion for stopping CPR, the probability of ROSC would be low if the rate of change in rSO 2 is less than 14.5%. Conclusions: The rate of change in the rSO 2 value during CPR might be a new index for the prediction of ROSC.