1Universitätsklinikum Leipzig Klinik und Poliklinik für Kardiologie Leipzig, Deutschland; 2Universitätsklinikum Leipzig Zentrale Notaufnahme Leipzig, Deutschland; 3Universitätsklinikum Leipzig Klinik und Poliklinik für Neurologie Leipzig, Deutschland; 4Universitätsklinikum Leipzig Interdisziplinäre Internistische Intensivmedizin Leipzig, Deutschland; 5Universitätsklinikum Leipzig Klinik und Poliklinik für Anästhesiologie Leipzig, Deutschland
Background: The effect of certification as Cardiac Arrest Center (CAC) on outcomes for patients with an of out-of-hospital cardiac arrest (OHCA) is incompletely known.
Aim: To evaluate the effect of CAC certification on survival of patients with nontraumatic OHCA.
Methods: All 790 consecutive adult patients admitted to our emergency department with nontraumatic OHCA from 01/2018 to 06/2023 were entered into our registry. Our institution was certified as CAC by the German Resuscitation Council in 11/2019. Standardized communication protocols with the emergency medical services to timely advise the receiving CAC on arrival time and characteristics of OHCA patients were established in October 2020. We compared patients admitted prior to 10/2020 to those admitted after 10/2020. The primary endpoint was a composite of all-cause death and cerebral performance category (CPC) of worse than 2 (i.e. ‘severe impairment’ or worse) at 90 days after arrest. Patients were stratified by CaRdiac Arrest Survival Score (CRASS), which estimates the probability of discharge with favourable neurological outcome.
Results: 432 patients treated before certification and communication protocol implementation were compared to 358 patients admitted after 10/2020 (sex [% male]: n=286 [66.2%] vs. n=238 [66.5%, p=0.94], age [years, median (interquartile range [IQR]): 68 (56-78) vs. 67 (55-78), before vs. after 10/2020, respectively, p=0.41]. Bystander resuscitation was performed in n=44 (43.9%) vs. n=163 (47.9%) of cases (p=0.43), initial ECG showed ventricular fibrillation or ventricular tachycardia in n=125 (28.9%) vs. n=88 (24.6%, p=0.17) and return of spontaneous circulation (ROSC) was present on admission in n=265 (61.3%) vs n=199 (55.6%, p=0.11) of patients. Overall CRASS was (median [IQR]) 15.45% (3.56-47.50).
The patients brought to our institution after October 2020 showed significantly worse CRASS (before implementation: 28.91 [8.71-59.87]; after: 6.91% [1.10-23.15], p<0.001). Follow-up at 90 days was complete in n=410 (94.9%) and n=342 (95.5%) of patients (before vs. after, respectively). Nonetheless, there was no significant difference in 90-day survival with CPC ≤2 (before: n=71 [17.1%] vs. after n=54 [15.7%], hazard ratio (HR) [95% confidence interval (95% CI)]: 1.07 [0.91-1.25], p= 0.35 [Log-Rank test]).
In patients with CRASS below 15.45%, i.e. below median, there was no significant difference in 90-day survival with favourable neurological outcome (before: n= 4 (3.1%), after: n=6 (2.9%), HR [95% CI]: 0.93 [0.75-1.17], p=0.38 [Log-Rank-Test]). In patients with CRASS above median, survival with favourable neurological status was significantly higher in patients admitted after full measure implementation, (before: n= 53 (24.9%), after: n=33 (35.9%), hazard ratio (HR) [95% CI]: 0.73 [0.54-0.98], p=0.03 [Log-Rank-Test]). In Cox regression analysis, we found a significant interaction between CRASS and CAC implementation (HR 0.98, 95% CI 0.97-0.99, p <0.001 for interaction)
Conclusion: For the sickest patients with low probability of survival after OHCA, treatment in a certified cardiac arrest center does not appear to make a difference. Patients with intermediate probability of survival appear to benefit from specialized treatment in a CAC, however, further analysis is warranted.