With a broad model cutoff, for example, centers could go from monitoring all children to monitoring just half, with the trade-off of missing only about 10% of those who are having subclinical seizures. “This is not perfect, but few models of diagnostic tests are perfect,” Dr. Abend commented. “So I’ve taken this as pretty positive, that given the variability of going multicenter to single center with only five pretty basic data points, we can cut the monitoring in half and only miss about 10%.”
“In the next version of this study, with cleaner data and clearer criteria for who is getting included, and maybe including more data points, not just the five variables, we may be able to do a lot better. I think if we could cut the monitoring by half, and miss only 5% of patients, that’s not ideal, but maybe then it’s about developing other strategies to try to catch those 5% more efficiently, or at least giving centers with limited resources a logical approach” for deciding whom to monitor, he added.
In the second study, investigators led by Dr. Rajsekar R. Rajaraman, a pediatric neurology fellow at the University of California, Los Angeles, Medical Center, assessed predictors of early subclinical seizures among children with traumatic brain injury admitted to the pediatric intensive care unit. Early seizures were defined as those occurring within 7 days of the injury.
The investigators identified the predictors in a combined cohort of 135 consecutive children from the UCLA Medical Center and the Children’s Hospital of Colorado, and validated them in a cohort of 44 children from the Children’s Hospital of Philadelphia.
Overall, 12.6% of the development cohort and 31.8% of the validation cohort had subclinical seizures on EEG. “The really worrisome thing about subclinical seizures is that 87.1% of these patients who had subclinical seizures went on to have status epilepticus,” Dr. Rajaraman noted in the press briefing.
In a multivariate analysis, three factors predicted the risk of subclinical seizures: age younger than 2 years (odds ratio for older children, 0.84), abusive head trauma as the mechanism of injury (odds ratio, 7.29), and intradural hematoma on a computed tomography scan (odds ratio could not be calculated because this factor was present in all children with subclinical seizures). Findings were similar for the risk subclinical status epilepticus.