Neurological prognostication in children after cardiac arrest

Smith AE, Friess SH. Neurological Prognostication in Children After Cardiac Arrest. Pediatr Neurol. 2020 Mar 15. pii: S0887-8994(20)30089-8. doi:10.1016/j.pediatrneurol.2020.03.010. [Epub ahead of print]

Abstract

Early after pediatric cardiac arrest, families and care providers struggle with the uncertainty of long-term neurological prognosis. Cardiac arrest characteristics such as location, intra-arrest factors, and postarrest events have been associated with outcome. We paid particular attention to postarrest modalities that have been shown to predict neurological outcome. These modalities include neurological examination, somatosensory evoked potentials, electroencephalography, and neuroimaging. There is no one modality that accurately predicts neurological prognosis. Thus, a multimodal approach should be undertaken by both neurologists and intensivists to present a clear and consistent message to families. Methods used for the prediction of long-term neurological prognosis need to be specific enough to identify indivuals with a poor outcome. We review the evidence evaluating children with coma, each with various etiologies of cardiac arrest, outcome measures, and timing of follow-up. ___________________________________________________________________________

From the article:

In summary, although the examination can be confounded, if performed later in a child’s hospital course, it can be helpful with prognostication of poor outcome, especially when assessing simple examination maneuvers such as pupil reactivity, respiratory drive, and motor response. However, the weaknesses of the aforementioned studies are apparent in that they are either retrospective or small prospective cohorts with a fair proportion of patients with poor outcome having withdrawal of life-sustaining therapies  and with rare multivariate analyses, thus not accounting for sedation effects. The AHA 2019 Scientific Statement on pediatric cardiac arrest recommends that early examination after return of spontaneous circulation (ROSC) be interpreted for prognostication with caution and that the predictive ability improves with serial examinations and time…

In conclusion, the studies presented in the previous sections demonstrate that SEPs can be helpful in predicting poor outcome in comatose children after cardiac arrest . However, the lack of a homogeneous pediatric cardiac population evaluated in the studies presented is a concerning weakness. Similar to the neurological examination, utilizing SEPs as a single modality for neurological prognostication after pediatric cardiac arrest is not recommended. Thus, the AHA 2019 Scientific Statement on pediatric cardiac arrest recommends the routine use of SEPs for neurological prognostication in children after cardiac arrest be done with extreme caution…

In conclusion, the aforementioned evidence supports using EEG as a postarrest modality predictor of both favorable and unfavorable outcomes at PICU or hospital discharge. The majority of quality evidence supports using background EEG features for these outcome measures. The current pediatric literature is limited by study size and retrospective study design. In 2015, the American Clinical Neurophysiology Society published a consensus statement on indications for continuous EEG in critically ill children. In this statement, continuous EEG for 24 hours is recommended to identify nonconvulsive seizures or status epilepticus in critically ill children with altered mental status after acute brain injury post-cardiac arrest. In addition, evidence is provided to recommend assessing for seizures if a critically ill child is being treated with neuromuscular blockade and at risk for seizures. This statement also mentions that EEG can aid in prognosis in children with hypoxic-ischemic injury after cardiac arrest. The AHA Pediatric Advanced Life Support 2015 guidelines state that EEG recordings done within seven days after ROSC can be helpful in prognostication at time of hospital discharge but should not be the only modality used…

In summary, MRI and HCT can be useful in prognostication after pediatric cardiac arrest. The current literature is limited by study size, variable timing of imaging, modalities of imaging, and inconsistency of the findings evaluated in each study. Further work should focus on comparison of regional injury patterns with whole-brain analysis for prognostication. Trends in the aforementioned literature suggest that regional injury in the basal ganglia and deep gray and occipital lobes is associated with poor outcomes. The AHA 2019 Scientific Statement on pediatric cardiac arrest recommends HCT as a useful tool to identify treatable intracranial injury, but evidence is insufficient to support use for prognostication, whereas brain MRI with DWI sequences done in the first three to seven days after ROSC may be useful to supplement other prognostication criterion…

Optimal prediction of neurological outcomes after pediatric cardiac arrest requires a multimodal approach incorporating the available data including cardiac arrest characteristics, neurological examination at least 24 hours from ROSC or normothermia, EEG background features, SEP responses, and neuroimaging. Advanced techniques including quantitative measures on EEG and MRI may provide new objective data from modalities that have been measured qualitatively previously. This review also highlights the lack of standardization in outcome measures and timing of assessments, which will be essential for moving the field of pediatric cardiac arrest forward.