The locally derived model shows satisfactory results, with good calibration and discriminative power. The local model specifically outperforms all other European systems in terms of discriminatory power in combined surgery subset.

Introduction/Objective: Survival and neurologic recovery after out-of-hospital cardiac arrest remain poor despite significant advances in the therapeutic approach. The study aimed to evaluate predictors of intrahospital survival and neurologic outcome among patients after outof-hospital cardiac arrest as well as to evaluate the influence of mild therapeutic hypothermia introduction on intrahospital survival and neurologic outcome among comatose patients after out-of-hospital cardiac arrest. Methods The research was conducted as a retrospective observational study among patients hospitalized at the Cardiac Intensive Care Unit of the Institute for Cardiovascular Diseases of Vojvodina from January 2007 until November 2019 as a result of an out-of-hospital cardiac arrest. Results. The research included 506 survivors of OHCA. Multivariate regression analysis showed that initial shockable rhythm, cardiopulmonary resuscitation efforts lasting no longer than 20 minutes and a Glasgow Coma Score above 8 at admission, were predictors of intrahospital survival and good neurological outcome. Introduction of mild therapeutic hypothermia improved intrahospital survival (54.1% vs. 24.4%; p < 0.0005) and neurological outcome (42.9% vs. 18.3%; p < 0.0005) in comatose patients with initial shockable rhythm. Conclusion. In our study group of out-of-hospital cardiac arrest patients, initial shockable rhythm, cardiopulmonary resuscitation efforts lasting no longer than 20min and a Glasgow Coma Score above 8 at admission were predictors of intrahospital survival and favourable neurological outcome. The introduction of mild therapeutic hypothermia significantly improved survival and neurological outcomes in comatose patients with initial shockable rhythms.

Funding Acknowledgements Type of funding sources: None. Introduction Out-of-hospital cardiac arrest (OHCA) is a major public health challenge and although rate of intrahospital survival increased over the last 40 years, it still remains poor (from 8,6% in 1976-1999 to 9,9% in 2000-2019). Different studies report that introduction of mild therapeutic hypothermia (TTM) improves survival and neurological outcome in comatose patients after OHCA.  Purpose The aim of this research was to evaluate influence of pre-hospital predictors related to cardiopulmonary resuscitation (CPR), neurological status and ECG changes at admission and early percutaneous coronary intervention (PCI) performed within 24h of admission on intrahospital survival and neurological outcome of OHCA patients. Methods The research was conducted as a retrospective cohort study of data taken from the hospital registry on OHCA from January 2007 until November 2019. The analyzed factors were: bystander CPR, duration of CPR until return of ROSC, initial rhythm, responsiveness upon admission defined as Glasgow Coma Score (GCS)&gt;8, presence of ST segment elevation (STEMI) on electrocardiography (ECG) and early PCI. The favorable neurological outcome was defined as a cerebral performance category scale (CPC)≤2. Results The research included 506 survivors of OHCA. Cardiac arrest was witnessed in 412 (81.4%), bystander CPR was performed in 197 (38.9%), CPR lasted ≤20min in 291 (57.5%), initial rhythm was shockable in 304 (60.1%) of patients. At admission 387 (76.5%) were comatose (GCS &lt; 8) and TTM was introduced in 177 (45.7%) of patients. ECG upon admission showed STEMI in 176 (34.8%) and early PCI was performed in 145 (28.6%) of patients. In-hospital mortality in our study group was 281 (55.5%) and 185 (36.6%) of patients had favorable neurological outcome. Multivariate regression analysis showed that initial shockable rhythm (OR 3.391 [2.310-4.977], p &lt; 0.0005), early PCI (OR 0.368 [0.226-0.599], p &lt; 0.0005), duration of CPR ≤20min (OR 4.249 [2.688-6.718], p &lt; 0.0005) and GCS &gt; 8 (OR 0.194 [0.110-0.343], p &lt; 0.0005) were independent predictors of in-hospital survival. Independent predictors of favorable neurological outcome were: initial shockable rhythm (OR 3.301 [2.002-5.441], p&lt; 0.0005), STEMI on ECG upon admission (OR 0.528 [0.326-0.853], p = 0.009), duration of CPR ≤20min (OR 5.144 [3.090-8.565], p&lt; 0.0005) and GCS &gt; 8 (OR 0.152 [0.088-0.260], p&lt; 0.0005). Introduction of TTM improved both intrahospital survival (54.1% vs. 24.4%; p &lt; 0.0005) and neurological outcome (33.5% vs. 11.6%; p &lt; 0.0005) in patients with initial shockable rhythm. Conclusion In our study group of OHCA patients of any origin, initial shockable rhythm, duration of CPR ≤20min and GCS &gt; 8 at admission influenced both intrahospital survival and favorable neurological outcome. Introduction of TTM significantly improved both survival and neurological outcome in comatose patients with initial shockable rhythm.