EEG features of brain injury during extracorporeal membrane oxygenation in children

Objective To examine EEG features of major pathophysiology in children undergoing extracorporeal membrane oxygenation (ECMO). Methods This was a single-center, retrospective study of 201 pediatric patients on ECMO, using the first 24 hours of continuous EEG (cEEG) monitoring, collating background activity and electrographic seizures (ES) with imaging, ECMO type, and outcome. Results Severely abnormal cEEG background occurred in 12% (25/201), and was associated with death (sensitivity 0.23, specificity 0.97). ES occurred in 16% (33/201) within 3.2 (0.6-20.3) hours (median [interquartile range]) of cEEG commencement, and higher ES burden was associated with death. ES was always associated with ipsilateral injury (p= 0.006), but occurred in only one-third of cases with abnormal imaging. In 28 patients with isolated hemisphere lesion, type of arterial ECMO cannulation was associated with side of injury: right carotid cannulation was associated with right hemisphere lesions, and ascending aorta cannulation with left hemisphere lesions (odds ratio, 0.29 [95% confidence interval, 0.08-0.98],p= 0.03). Conclusions After starting ECMO, cEEG background activity has the potential to inform prognosis. Type of arterial (carotid vs aortic) ECMO correlates with side of focal cerebral injury, which in approximate to 33% is associated with presence of ES. We hypothesize that the differential distribution reflects abnormal flow dynamics or embolic injury.