ID:39 FC-D08-3 External Validation of the TiPS65 Score Predicting Neurologic Outcome for Out-of-Hospital Cardiac Arrest Patients Receiving Extracorporeal Cardiopulmonary Resuscitation

Background: The TiPS65 score serves as a prognostic indicator for neurologic outcomes among out-of-hospital cardiac arrest (OHCA) patients undergoing extracorporeal cardiopulmonary resuscitation (ECPR). Although this scoring system has undergone validation exclusively within Japan, its applicability remains uncertain in other countries. Our objective is to conduct an external validation of this score in different population. Methods: Our study encompassed adult OHCA patients who underwent ECPR between January 2014 and June 2023 at our institution. Patients experiencing unwitnessed cardiac arrest or those managed under unstandardized ECMO protocols were excluded. The primary outcome was a favorable neurologic outcome at hospital discharge, defined as a Cerebral Performance Category of 1 or 2. We assessed the C-statistic and predictive performances of the TiPS65 score. Results: A total of 130 patients met the study criteria, with a mean age of 56.9 years. Of these patients, 62 (47.7%) were successfully weaned off ECMO support, with 31.5% (n = 41) surviving to discharge, and 21.5% (n = 28) achieving favorable neurologic outcomes. The TiPS65 score exhibited a C-statistic of 0.744 (95% confidence interval (CI): 0.654-0.833). Setting the TiPS65 score cut-off value at > 1 yielded very high sensitivity 0.964 (95% CI: 0.896-1.000) and negative predictive value 0.972 (95% CI: 0.919-1.026). TiPS65 score 0 or 1 are with dismal neurologic outcomes after ECPR. By incorporating hemoglobin and arterial CO2 level in initial blood gas assessment to the TiPS65 score, the C-statistic of the modified scoring systems significantly improved to 0.811 (p-value = 0.01). Conclusion: External validation of the TiPS65 score demonstrated favorable efficacy for predicting neurologic outcomes in our cohort. TiPS65 score 0-1 can be considered as a relative contraindication of ECPR. The TiPS65 score can be supportive in the patient selection for ECPR.