Seizure severity is correlated with severity of hypoxic ischemic Injury in abusive head trauma

Andra L. Dingman, Nicholas V. Stence, Brent R. O'Neill, Stefan H. Sillau, Kevin E. Chapman. Seizure Severity is Correlated with Severity of Hypoxic Ischemic Injury in Abusive Head Trauma . Pediatric Neurology.  In  press.

Abstract

Objective: to characterize hypoxic ischemic injury (HII) and seizures in abusive head trauma (AHT). Methods: We performed a retrospective study over 4 years of 58 children with moderate or severe traumatic brain injury (TBI) due to AHT. Continuous electroencephalograms (cEEGs) and magnetic resonance images (MRIs) were scored. Results: Electrographic seizures (51.2%) and HII (77.4%) were common in our cohort. Younger age was associated with electrographic seizures (no seizures: median age 13.5 months, IQR 5-25 months vs seizures: 4.5 months IQR 3-9.5, p=0.001). Severity of HII was also associated with seizures (no seizures: median HII score 1.0 IQR 0-3 vs seizures: 4.5 IQR 3-8, p=0.01), but traumatic injury severity was not associated with seizures (no seizures: mean injury score 3.78 ± 1.68 vs seizures: 3.83 ± 0.95, p=0.89). There was a significant correlation between HII severity and seizure burden when controlling for patient age (rs=0.61, p<0.001). The ratio of restricted diffusion volume to total brain volume (RD ratio) was smaller on MRIs done early (median RD ratio 0.03, IQR 0-0.23 in MRIs done within 2 days vs median RD ratio 0.13, IQR 0.01-0.43 in MRIs done after 2 days, p=0.03). Conclusions: Electrographic seizures are common in children with moderate to severe TBI from AHT, and therefore children with suspected AHT should be monitored with cEEG. Severity of hypoxic ischemic brain injury is correlated with severity of seizures, and evidence of HII on MRI may evolve over time. Therefore, children with high seizure burden should be re-imaged to evaluate for evolving HII.