Impact of the SIGN head injury guidelines and NHS 4-hour emergency target on hospital admissions for head injury in Scotland: an interrupted times series

Abstract

ObjectivesHead injury is a common reason for emergency department (ED) attendance. Around 1% of patients have life-threatening injuries, while 80% of patients are discharged. National guidelines (Scottish Intercollegiate Guidelines Network (SIGN)) were introduced in Scotland with the aim of achieving early identification of those with acute intracranial lesions yet safely reducing hospital admissions.This study aims to assess the impact of these guidelines and any effect the national 4-hour ED performance target had on hospital admissions for head injury.SettingAll Scottish hospitals between April 1998 and March 2016.ParticipantsPatients admitted to hospital for head injury or traumatic brain injury (TBI) diagnosed by CT imaging identified using administrative Scottish Information Services Division data. There are 275 hospitals in Scotland. In 2015/2016, there were 571 221 emergency hospital admissions in Scotland.InterventionsThe SIGN head injury guidelines introduced in 2000 and 2009. The 4-hour ED target introduced in 2004.OutcomesThe monthly rate of hospital admissions for head injury and traumatic brain injury.Study designAn interrupted time series analysis.ResultsThe first guideline was associated with a reduction in monthly admissions of 0.14 (95% CI 0.09 to 4.83) per 100 000 population. The 4-hour target was associated with a monthly increase in admissions of 0.13 (95% CI 0.06 to 0.20) per 100 000 population. The second guideline reduced monthly admissions by 0.09 (95% CI−0.13 to −0.05) per 100 000 population. These effects varied between age groups.The guidelines were associated with increased admissions for patients with injuries identified by CT imaging—guideline 1: 0.06 (95% CI 0.004 to 0.12); guideline 2: 0.05 (95% CI 0.04 to 0.06) per 100 000 population.ConclusionIncreased CT imaging of head injured patients recommended by SIGN guidelines reduced hospital admissions. The 4-hour ED target and the increased identification of TBI by CT imaging acted to undermine this effect.

Evaluation of the impact of the NICE head injury guidelines on inpatient mortality from traumatic brain injury: an interrupted time series analysis

“…Increased imaging was intended to reduce hospital admissions by reducing diagnostic uncertainty but the first NICE guideline coincided with the introduction of the 4 hour target 8 20. We have shown, using Scottish data assessing the impact of similar Scottish Intercollegiate Guidelines Network (SIGN) guidelines (introduced at a different time to the 4-hour target), that the 4-hour target acted to undermine this reduction and cause a large increase in hospital admissions 21. No mortality benefit was found at the time of the introduction of the 4-hour target in England.…”

Rationalising neurosurgical head injury referrals: development and validation of the Liverpool Head Injury Tomography Score (Liverpool HITS) for mild TBI

“…Indeed, a recent systematic review and meta-analysis suggests that 3.5% of those with a mild TBI go on to receive neurosurgical intervention 15 . In contrast, Neurosurgical referrals for trauma are constantly increasing and have increased by 50% in the last 5 years in the UK 16,17 . This increase 18 coincides with recent surveys that suggest referrers find many aspects of referral to a neurosurgical centre difficult, and a lack of training in under-and postgraduate medical programmes indicate that many doctors may not be aware of what injuries in mild TBI constitute a neurosurgical emergency which merits referral 19,20 .…”

“…This is more pertinent for referral centres without readily available access to a neurosurgical centre 26 . In many local trusts, all computed tomography (CT) head scans reported as 'abnormal' after a mild TBI are often referred to neurosurgical centres, leading to inappropriate referrals 17,25,27 . Indeed, at our centre roughly 82% of these referrals are not accepted for transfer and managed locally.…”

“…This accounts for up to 1200 extraneous referrals per centre per year 28 . As very few mild TBI patients end up receiving neurosurgical management, this means that most referrals are not accepted for transfer to neurosurgical centres and are managed locally 17,29 . There is little data available regarding the scope of avoidable neurosurgical referrals for mild TBI and the impact that .…”

Rationalising neurosurgical head injury referrals: The development and implementation of the Liverpool Head Injury Tomography Score (Liverpool HITS) for mild traumatic brain injury

“…This accounts for up to 1200 extraneous referrals per centre per year 28 . As very few mild TBI patients end up receiving neurosurgical management, this means that most referrals are not accepted for transfer to neurosurgical centres and are managed locally 17, 29 . There is little data available regarding the scope of avoidable neurosurgical referrals for mild TBI and the impact that being able to identify this may have.…”