How did two head injury rules compare at identifying traumatic brain lesions?

Details

The study compared the Canadian CT Head Rule (CCHR) and New Orleans Criteria (NOC) for detecting any traumatic intracranial lesion on computed tomography (CT) in patients with a Glasgow Coma Scale (GCS) score of 15. It also assessed detection of clinically important brain injury and the need for neurosurgical intervention. The CCHR was additionally assessed in a larger group presenting with GCS scores of 13 to 15.

This prospective cohort study was conducted at a U.S. Level I trauma center. It consecutively enrolled mildly head-injured adults who came to the emergency department with witnessed loss of consciousness, disorientation or amnesia and a GCS score of 13 to 15. The rules were compared in patients with a GCS score of 15. The primary outcome was prediction of any traumatic intracranial injury on CT. Secondary outcomes were clinically important brain injury on CT and the need for neurosurgical intervention.

Of 431 enrolled patients, 314 (73%) had a GCS score of 15; 22 of those 314 (7%) had a traumatic intracranial lesion on CT. Clinically important brain injury was found in 11 of 314 (3.5%), and 3 of 314 (1.0%) required neurosurgical intervention.

For any traumatic intracranial lesion on CT, both rules had 100% sensitivity (95% confidence interval [CI]: 82%–100%); specificity was 36.3% (95% CI: 31%–42%) for CCHR versus 10.2% (95% CI: 7%–14%) for NOC. For clinically important brain lesions, both had 100% sensitivity (95% CI: 68%–100%); specificity was 35% (95% CI: 30%–41%) for CCHR versus 9.9% (95% CI: 7%–14%) for NOC. For predicting the need for neurosurgical intervention, both had 100% sensitivity (95% CI: 31%–100%); specificity was 80.7% (95% CI: 76%–85%) for CCHR versus 9.6% (95% CI: 7%–14%) for NOC.

Among all 431 patients with GCS scores of 13 to 15, CCHR sensitivity was 100% (95% CI: 84%–100%) for the 27 patients with clinically important brain injury and 100% (95% CI: 46%–100%) for the five who needed neurosurgical intervention. In this U.S. sample of mildly head-injured patients, the rules had equally high sensitivities for all three outcomes, but CCHR was more specific. A larger cohort is needed to validate these findings.