Temporal trends in head injury outcomes from 2003 to 2009 in England and Wales

Background: Case fatality rates after blunt head injury (HI) did not improve in England and Wales between 1994 and 2003. The United Kingdom National Institute of Clinical Excellence subsequently published HI management guidelines, including the recommendation that patients with severe head injuries (SHIs) should be treated in specialist neuroscience units (NSU). The aim of this study was to investigate trends in case fatality and location of care since the introduction of national HI clinical guidelines. Methods: We conducted a retrospective cohort study using prospectively recorded data from the Trauma and Audit Research Network (TARN) database for patients presenting with blunt trauma between 2003 and 2009. Temporal trends in log odds of death adjusted for case mix were examined for patients with and without HI. Location of care for patients with SHI was also studied by examining trends in the proportion of patients treated in non-NSUs. Results: Since 2003, there was an average 12% reduction in adjusted log odds of death per annum in patients with HI (n=15,173), with a similar but smaller trend in non-HI trauma mortality (n=48,681). During the study period, the proportion of patients with HI treated entirely in non-NSUs decreased from 31% to 19%, (p <0.01). Interpretation: The reduction in odds of death following HI since 2003 is consistent with improved management following the introduction of national HI guidelines and increased treatment of SHI in NSUs.