Article Text

Download PDFPDF

049 Development of a clinical decision rule for the early safe discharge of patients with mild traumatic brain injury and findings on CT brain scan: a retrospective cohort study
  1. Carl Marincowitz1,
  2. Fiona Lecky2,
  3. Victoria Allgar3,
  4. Peter Hutchinson4,
  5. Hadir Elbeltagi5,
  6. Faye Johnson5,
  7. Eimhear Quinn5,
  8. Silvia Tarantino4,
  9. Will Townend1,
  10. Angelos Kolias4
  1. 1Hull and East Yorkshire Hospitals NHS Trust and Hull York Medical School
  2. 2University of Sheffield
  3. 3Hull York Medical School
  4. 4Division of Neurosurgery, Department of Clinical Neurosciences, Addenbrooke’s Hospital and University of Cambridge
  5. 5Salford Royal Hospital


Background International guidelines recommend routine hospital admission for all patients with mild traumatic brain injury (TBI) who have injuries on CT brain scan. Only a small proportion of these patients require neurosurgical or critical care intervention. We aimed to develop an accurate clinical decision rule to identify low risk patients safe for discharge from the emergency department (ED) and facilitate earlier referral of those requiring intervention.

Method and results A retrospective cohort study of case-notes of patients admitted with initial GCS13-15 and injuries identified by CT was completed. Data on a primary outcome measure of clinically important deterioration (indicating need for hospital admission) and secondary outcome of neurosurgery, ICU admission or intubation (indicating need for neurosurgical admission) were collected. Multivariable logistic regression was used to derive models and a risk score predicting deterioration using routinely reported candidate variables identified in a systematic review. We compared the performance of this new risk score with the Brain Injury Guideline (BIG) criteria, derived in the USA.

Abstract 049 Figure 1

Population selection

Abstract 049 Table 1

Model performance

Abstract 049 Table 2

Performance of risk score and BIG criteria

Conclusions 1699 patients were included from 3 English Major Trauma Centres. 27.7% (95% CI: 25.5% to 29.9%) met the primary, and 13.1% (95% CI: 11.6% to 14.8%) met the secondary, outcome of deterioration. The derived clinical decision rule suggests that patients with simple skull fractures or intracranial bleeding less than 5 mm in diameter who are fully conscious could be safely discharged from the Emergency Department. The decision rule achieved a sensitivity of 99.5% (95% CI: 98.1% to 99.9%) and specificity of 7.4% (95% CI: 6% to 9.1%) to the primary outcome. The BIG criteria achieved the same sensitivity but lower specificity (5%).

Our empirical models showed good predictive performance and outperformed the BIG criteria. This would potentially allow ED discharge of one in twenty patients currently admitted for observation. However prospective external validation and economic evaluation is required.

Statistics from

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.