Maayke Hunfeld

131 Cause of death death (47%)(15). How can this difference between the findings of Du Pont et al and our findings be explained? First, the definition of BD is not identical in both studies and dependent from criteria that differ between countries, making a comparison difficult. In our study, we defined BD as clinically BD (see the ‘Materials and Methods’ section). Additionally, in 2016, the Dutch guideline was changed with one of the prerequisites not to determine BD until 12-24 hours after the CPR event (20). This implies that according to the previous guideline, patients admitted before 2016 may have been declared BD by clinicians, but did not fulfill the BD criteria of the present study (wait for at least 12-24 hr with neurologic examination). This may have given an underestimation of the total amount of BD patients in our cohort. Second, were the children in our study initially in a better condition after ROC compared to the study in the United States, resulting in less BD? If so, this could be due to the setting in the Netherlands: a higher incidence in Automatic External Defibrillator (AED) use and bystander CPR, the availability of Helicopter Emergency Medical Service (HEMS), short transfer time from the scene to the hospital (21- 24). Indeed, as part of national protocol, in vitally compromised children a HEMS is activated consisting of a physician and specialized nurse for quick advanced pediatric life support at site. In addition, in the Netherlands, a text message CA response system exist for volunteers trained in resuscitation and AED use. However, we must emphasize this hypothesis is purely speculative, because documentation of these variables in both studies are lacking. Although in our study cohort survivors were discharged from the PICU with favorable outcome (median PCPC= 2; IQR, 1-3), we didn’t focus on long-term outcome in different domains (e.g., neuropsychological assessments and quality of life). Could it be possible that in the U.S. cohort of Du Pont et al survivors have more severe long- term neurologic deficits due to lower percentage of WLST (15)? In all WLST-Neuro patients, the decision-making was based on neurologic examination. However, besides neurologic examination, there was great variability between other factors contributing to the decision-making (e.g., prearrest medical conditions, severity of other injuries/organ failure, brain imaging and type, EEG, SSEP). In most of these patients, at least one modality beside neurologic examination was used for decision making. Until 2017, there was no standardized care for comatose, non-BD children after CA at our PICU and ancillary tests (EEG, imaging) remained at the discretion of the treating physician (pediatric intensivist and pediatric neurologist). In 2017, we developed standardized post-CA care for these patients, both therapeutic and diagnostic. With regard to diagnostics, cEEG recordings are started as soon as possible after PICU admission and all children undergo imaging by MRI approximately 5 days after the arrest. When sedation or analgesics are administered 4