Risk score determines whether kids with abnormal CT scans require ICU care.
Most children with mild traumatic brain injury have normal CT scans – a scenario often referred to as a concussion. If a CT scan is abnormal, however, a child’s condition is at higher risk of deteriorating, requiring monitoring in a hospital. But there is little consensus about how closely such children should be monitored. Some such children recover well, while others experience a neurological decline and need surgery to relieve brain swelling.

In new research, pediatric neurosurgeons at Washington University School of Medicine in St. Louis developed a risk scoring system intended to help determine whether a child with mild traumatic brain injury and an abnormal CT scan can be monitored safely in a general hospital ward or requires the increased surveillance of an intensive care unit (ICU).

The study was published Feb. 13 in the journal JAMA Pediatrics.

The researchers plumbed data from more than 40,000 children evaluated from 2004 to 2006 at 25 North American hospital emergency departments, including St. Louis Children’s Hospital.

The information originally was gathered in a study conducted by the Pediatric Emergency Care Applied Research Network (PECARN), which established the standard framework for deciding whether a child with a mild head injury should have a head CT scan. Limbrick and his colleagues returned to this data set for guidance on how to handle the subset of children who receive CT scans and are shown to have abnormal findings on the scans. Of the 40,000 children enrolled in the study, 15,000 had CT scans following mild traumatic brain injury. Of these, 839 patients showed abnormalities on the CT scan, such as a brain bleed.

These types of injuries are serious enough that some children will experience a neurological decline and need surgery to relieve swelling or pressure on the brain.

Based on an analysis of the injuries these patients suffered and how they recovered, the investigators developed a risk score ranging from zero to 24 points, called the Children’s Intracranial Injury Decision Aid score (CHIIDA). Higher scores indicate the patient is at higher risk of neurological decline and should receive increased monitoring. Lower scores mean a patient is at lower risk of neurological decline. A score of zero indicates the child is at very low risk. The chance that such a child would go on to experience a neurological decline that requires surgery is less than 1.5 percent, according to the analysis.

As a general rule, the authors suggested, children with scores of less than three points can safely be admitted to a general ward. Patients with higher scores should receive increased surveillance up to and including that provided in an ICU.

The score is determined by four factors that the researchers found most predictive of patient outcomes. One factor is called the Glasgow Coma Scale (GCS).

While the GCS is based on a doctor’s interaction with a patient, the other three factors are determined based on an analysis of a CT scan. The biggest risk factors seen in a CT image are a depressed skull fracture and what is referred to as a midline shift, when the symmetrical structures of the brain are pushed off–center. The final risk factor is an epidural hematoma — a blood clot between the outer layer of the brain’s protective covering and the inside of the skull.

Patients with mild traumatic brain injury who show these features on a CT scan and also have a lower GCS score are at high risk of experiencing a neurological decline and, according to the researchers, should be cared for in an ICU.