The Canadian CT Head Rule for patients with minor head injury

Lancet. 2001 May 5;357(9266):1391-6. doi: 10.1016/s0140-6736(00)04561-x.

Abstract

Background: There is much controversy about the use of computed tomography (CT) for patients with minor head injury. We aimed to develop a highly sensitive clinical decision rule for use of CT in patients with minor head injuries.

Methods: We carried out this prospective cohort study in the emergency departments of ten large Canadian hospitals and included consecutive adults who presented with a Glasgow Coma Scale (GCS) score of 13-15 after head injury. We did standardised clinical assessments before the CT scan. The main outcome measures were need for neurological intervention and clinically important brain injury on CT.

Findings: The 3121 patients had the following characteristics: mean age 38.7 years); GCS scores of 13 (3.5%), 14 (16.7%), 15 (79.8%); 8% had clinically important brain injury; and 1% required neurological intervention. We derived a CT head rule which consists of five high-risk factors (failure to reach GCS of 15 within 2 h, suspected open skull fracture, any sign of basal skull fracture, vomiting >2 episodes, or age >65 years) and two additional medium-risk factors (amnesia before impact >30 min and dangerous mechanism of injury). The high-risk factors were 100% sensitive (95% CI 92-100%) for predicting need for neurological intervention, and would require only 32% of patients to undergo CT. The medium-risk factors were 98.4% sensitive (95% CI 96-99%) and 49.6% specific for predicting clinically important brain injury, and would require only 54% of patients to undergo CT.

Interpretation: We have developed the Canadian CT Head Rule, a highly sensitive decision rule for use of CT. This rule has the potential to significantly standardise and improve the emergency management of patients with minor head injury.

Publication types

  • Clinical Trial
  • Multicenter Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Brain Injuries / diagnosis*
  • Brain Injuries / etiology
  • Canada
  • Craniocerebral Trauma / complications
  • Craniocerebral Trauma / diagnosis*
  • Craniocerebral Trauma / etiology
  • Emergency Service, Hospital / statistics & numerical data*
  • Female
  • Glasgow Coma Scale
  • Humans
  • Male
  • Middle Aged
  • Practice Guidelines as Topic
  • Prospective Studies
  • Sensitivity and Specificity
  • Tomography, X-Ray Computed