Distinct profiles of cerebral oxygenation in focal vs. secondarily generalized EEG seizures in children undergoing cardiac surgery

Seizures are common in children undergoing cardiopulmonary bypass (CPB). Cerebral oxygen saturation (ScO ) by near-infrared spectroscopy is routinely monitored in many centers, but the relations between the levels and changes of ScO and brain injuries remain incompletely understood. We aimed to analyze the postoperative profiles of ScO and cerebral blood flow velocity in different types of EEG seizures in relation to brain injuries on MRI. We monitored continuous EEG and ScO in 337 children during the first 48 h after CPB, which were analyzed in 3 h periods. Cerebral blood flow peak systolic velocity (PSV) in the middle cerebral artery was measured daily by transcranial Doppler. Postoperative cerebral MRI was performed before hospital discharge. Based on the occurrence and spreading types of seizures, patients were divided into three groups as patients without seizures (Group N; = 309), those with focal seizures (Group F; = 13), or with secondarily generalized seizures (Group G; = 15). There were no significant differences in the onset time and duration of seizures and incidence of status epilepticus between the two seizures groups ( ≥ 0.27). ScO increased significantly faster across Group N, Group G, and Group F during the 48 h (