Hospital admissions with head injury following publication of NICE guidance

Challenges of the Effectiveness of Traumatic Brain Injuries Biomarkers in the Sports-Related Context

Traumatic brain injury affects 69 million people every year. One of the main limitations in managing TBI patients is the lack of univocal diagnostic criteria, including the absence of standardized assessment methods and guidelines. Computerized axial tomography is the first-choice examination, despite the limited prevalence of positivity; moreover, its performance is undesirable due to the risk of radiological exposure, prolonged stay in emergency departments, inefficient use of resources, high cost, and complexity. Furthermore, immediacy and accuracy in diagnosis and management of TBIs are critically unmet medical needs. Especially in the context of sports-associated TBI, there is a strong need for prognostic indicators to help diagnose and identify at-risk subjects to avoid their returning to play while the brain is still highly vulnerable. Fluid biomarkers may emerge as new prognostic indicators to develop more accurate prediction models, improving risk stratification and clinical decision making. This review describes the current understanding of the cellular sources, temporal profile, and potential utility of leading and emerging blood-based protein biomarkers of TBI; its focus is on biomarkers that could improve the management of mild TBI cases and can be measured readily and directly in the field, as in the case of sports-related contexts.

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

OBJECTIVE

To evaluate the impact of National Institute for Health and Care Excellence (NICE) head injury guidelines on deaths and hospital admissions caused by traumatic brain injury (TBI).

SETTING

All hospitals in England between 1998 and 2017.

PARTICIPANTS

Patients admitted to hospital or who died up to 30 days following hospital admission with International Classification of Diseases (ICD) coding indicating the reason for admission or death was TBI.

INTERVENTION

An interrupted time series analysis was conducted with intervention points when each of the three guidelines was introduced. Analysis was stratified by guideline recommendation specific age groups (0-15, 16-64 and 65+).

OUTCOME MEASURES

The monthly population mortality and admission rates for TBI.

STUDY DESIGN

An interrupted time series analysis using complete Office of National Statistics cause of death data linked to hospital episode statistics for inpatient admissions in England.

RESULTS

The monthly TBI mortality and admission rates in the 65+ age group increased from 0.5 to 1.5 and 10 to 30 per 100 000 population, respectively. The increasing mortality rate was unaffected by the introduction of any of the guidelines.The introduction of the second NICE head injury guideline was associated with a significant reduction in the monthly TBI mortality rate in the 16-64 age group (-0.005; 95% CI: -0.002 to -0.007).In the 0-15 age group the TBI mortality rate fell from around 0.05 to 0.01 per 100 000 population and this trend was unaffected by any guideline.

CONCLUSION

The introduction of NICE head injury guidelines was associated with a reduced admitted TBI mortality rate after specialist care was recommended for severe TBI. The improvement was solely observed in patients aged 16-64 years.The cause of the observed increased admission and mortality rates in those 65+ and potential treatments for TBI in this age group require further investigation.

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

OBJECTIVES

Head 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.

SETTING

All Scottish hospitals between April 1998 and March 2016.

PARTICIPANTS

Patients 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.

INTERVENTIONS

The SIGN head injury guidelines introduced in 2000 and 2009. The 4-hour ED target introduced in 2004.

OUTCOMES

The monthly rate of hospital admissions for head injury and traumatic brain injury.

STUDY DESIGN

An interrupted time series analysis.

RESULTS

The 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.

CONCLUSION

Increased 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.

A protocol for the development of a prediction model in mild traumatic brain injury with CT scan abnormality: which patients are safe for discharge?

BACKGROUND

Head injury is an extremely common clinical presentation to hospital emergency departments (EDs). Ninety-five percent of patients present with an initial Glasgow Coma Scale (GCS) score of 13-15, indicating a normal or near-normal conscious level. In this group, around 7% of patients have brain injuries identified by CT imaging but only 1% of patients have life-threatening brain injuries. It is unclear which brain injuries are clinically significant, so all patients with brain injuries identified by CT imaging are admitted for monitoring. If risk could be accurately determined in this group, admissions for low-risk patients could be avoided and resources could be focused on those with greater need.This study aims to (a) estimate the proportion of GCS13-15 patients with traumatic brain injury identified by CT imaging admitted to hospital who clinically deteriorate and (b) develop a prognostic model highly sensitive to clinical deterioration which could help inform discharge decision making in the ED.

METHODS

A retrospective case note review of 2000 patients with an initial GCS13-15 and traumatic brain injury identified by CT imaging (2007-2017) will be completed in two English major trauma centres. The prevalence of clinically significant deterioration including death, neurosurgery, intubation, seizures or drop in GCS by more than 1 point will be estimated. Candidate prognostic factors have been identified in a previous systematic review. Multivariable logistic regression will be used to derive a prognostic model, and its sensitivity and specificity to the outcome of deterioration will be explored.

DISCUSSION

This study will potentially derive a statistical model that predicts clinically relevant deterioration and could be used to develop a clinical risk tool guiding the need for hospital admission in this group.

Long-term structural changes after mTBI and their relation to post-concussion symptoms

PRIMARY OBJECTIVE

To investigate sustained structural changes in the long-term (>1 year) after mild traumatic brain injury (mTBI) and their relationship to ongoing post-concussion syndrome (PCS).

RESEARCH DESIGN

Morphological and structural connectivity magnetic resonance imaging (MRI) data were acquired from 16 participants with mTBI and nine participants without previous head injury.

MAIN OUTCOMES AND RESULTS

Participants with mTBI had less prefrontal grey matter and lower fractional anisotropy (FA) in the anterior corona radiata and internal capsule. Furthermore, PCS severity was associated with less parietal lobe grey matter and lower FA in the corpus callosum.

CONCLUSIONS

There is evidence for both white and grey matter damage in participants with mTBI over 1 year after injury. Furthermore, these structural changes are greater in those that report more PCS symptoms, suggesting a neurophysiological basis for these persistent symptoms.

Impact of UK Primary Care Policy Reforms on Short-Stay Unplanned Hospital Admissions for Children With Primary Care-Sensitive Conditions

PURPOSE

We aimed to assess the impact of UK primary care policy reforms implemented in April 2004 on potentially avoidable unplanned short-stay hospital admissions for children with primary care-sensitive conditions.

METHODS

We conducted an interrupted time series analysis of hospital admissions for all children aged younger than 15 years in England between April 2000 and March 2012 using data from National Health Service public hospitals in England. The main outcomes were annual short-stay (<2-day) unplanned hospital admission rates for primary care-sensitive infectious and chronic conditions.

RESULTS

There were 7.8 million unplanned admissions over the study period. More than one-half (4,144,729 of 7,831,633) were short-stay admissions for potentially avoidable infectious and chronic conditions. The primary care policy reforms of April 2004 were associated with an 8% increase in short-stay admission rates for chronic conditions, equivalent to 8,500 additional admissions, above the 3% annual increasing trend. Policy reforms were not associated with an increase in short-stay admission rates for infectious illness, which were increasing by 5% annually before April 2004. The proportion of primary care-referred admissions was falling before the reforms, and there were further sharp reductions in 2004.

CONCLUSIONS

The introduction of primary care policy reforms coincided with an increase in short-stay admission rates for children with primary care-sensitive chronic conditions, and with more children being admitted through emergency departments. Short-stay admission rates for primary care-sensitive infectious illness increased more steadily and could be related to lowered thresholds for hospital admission.

Multimodal imaging of mild traumatic brain injury and persistent postconcussion syndrome

BACKGROUND

Persistent postconcussion syndrome (PCS) occurs in around 5-10% of individuals after mild traumatic brain injury (mTBI), but research into the underlying biology of these ongoing symptoms is limited and inconsistent. One reason for this could be the heterogeneity inherent to mTBI, with individualized injury mechanisms and psychological factors. A multimodal imaging study may be able to characterize the injury better.

AIM

To look at the relationship between functional (fMRI), structural (diffusion tensor imaging), and metabolic (magnetic resonance spectroscopy) data in the same participants in the long term (>1 year) after injury. It was hypothesized that only those mTBI participants with persistent PCS would show functional changes, and that these changes would be related to reduced structural integrity and altered metabolite concentrations.

METHODS

Functional changes associated with persistent PCS after mTBI (>1 year postinjury) were investigated in participants with and without PCS (both n = 8) and non-head injured participants (n = 9) during performance of working memory and attention/processing speed tasks. Correlation analyses were performed to look at the relationship between the functional data and structural and metabolic alterations in the same participants.

RESULTS

There were no behavioral differences between the groups, but participants with greater PCS symptoms exhibited greater activation in attention-related areas (anterior cingulate), along with reduced activation in temporal, default mode network, and working memory areas (left prefrontal) as cognitive load was increased from the easiest to the most difficult task. Functional changes in these areas correlated with reduced structural integrity in corpus callosum and anterior white matter, and reduced creatine concentration in right dorsolateral prefrontal cortex.

CONCLUSION

These data suggest that the top-down attentional regulation and deactivation of task-irrelevant areas may be compensating for the reduction in working memory capacity and variation in white matter transmission caused by the structural and metabolic changes after injury. This may in turn be contributing to secondary PCS symptoms such as fatigue and headache. Further research is required using multimodal data to investigate the mechanisms of injury after mTBI, but also to aid individualized diagnosis and prognosis.

The cost-effectiveness of diagnostic management strategies for adults with minor head injury

STUDY OBJECTIVE

To estimate the cost-effectiveness of diagnostic management strategies for adults with minor head injury.

METHODS

A mathematical model was constructed to evaluate the incremental costs and effectiveness (Quality Adjusted Life years Gained, QALYs) of ten diagnostic management strategies for adults with minor head injuries. Secondary analyses were undertaken to determine the cost-effectiveness of hospital admission compared to discharge home and to explore the cost-effectiveness of strategies when no responsible adult was available to observe the patient after discharge.

RESULTS

The apparent optimal strategy was based on the high and medium risk Canadian CT Head Rule (CCHRhm), although the costs and outcomes associated with each strategy were broadly similar. Hospital admission for patients with non-neurosurgical injury on CT dominated discharge home, whilst hospital admission for clinically normal patients with a normal CT was not cost-effective compared to discharge home with or without a responsible adult at £39 and £2.5 million per QALY, respectively. A selective CT strategy with discharge home if the CT scan was normal remained optimal compared to not investigating or CT scanning all patients when there was no responsible adult available to observe them after discharge.

CONCLUSION

Our economic analysis confirms that the recent extension of access to CT scanning for minor head injury is appropriate. Liberal use of CT scanning based on a high sensitivity decision rule is not only effective but also cost-saving. The cost of CT scanning is very small compared to the estimated cost of caring for patients with brain injury worsened by delayed treatment. It is recommended therefore that all hospitals receiving patients with minor head injury should have unrestricted access to CT scanning for use in conjunction with evidence based guidelines. Provisionally the CCHRhm decision rule appears to be the best strategy although there is considerable uncertainty around the optimal decision rule. However, the CCHRhm rule appears to be the most widely validated and it therefore seems appropriate to conclude that the CCHRhm rule has the best evidence to support its use.

Patients with syncope in a German emergency department: description of patients and processes

BACKGROUND

We studied the characteristics and resource utilization of patients with syncope in a German emergency department (ED).

METHODS

We carried out a single-center retrospective analysis of patients with syncope who presented to the ED of the Klinikum Nürnberg (a municipal hospital in Nuremberg, Germany).

RESULTS

Among the 28 477 patients who presented to the ED from 15 May 2009 to 30 September 2009, 440 (1.5%) presented with syncope. Their mean age was 62 years (standard deviation, 20 years); 50.4% were women, 43.4% were over age 70, 11.8% had cardiogenic and 4.8% neurological syncope, and 18.2% had more than two comorbid conditions. 20.7% were discharged after evaluation in the ED, 14.1% were brielfly hospitalized in the ED's clinical observation unit, and 56.6% were admitted to one of the hospital's specialty wards. 8.6% left the ED against medical advice. All of the syncope patients were evaluated by history-taking, physical examination, and 12-lead electrocardiogragraphy (ECG); ECG revealed abnormal findings in 36.4% of patients. Nearly all patients also underwent laboratory testing, which revealed hyponatremia (a serum sodium concentration under 130 mmol/L) in 5.9% and a serum creatinine level above 2 mg/dL in 5.3%. Many underwent technology-intensive tests such as cranial computed tomography (129 patients), but these tests only rarely yielded abnormal findings (3.1%). 27% of the syncope patients underwent Doppler ultrasonography of the vessels supplying the brain, with abnormal findings in 6.7% of cases. (Orthostatic testing was performed in 14.5% of the patients and was positive in 26.6%.)

CONCLUSION

Many patients presenting with syncope to a German ED are elderly, and multiple comorbidities are common. Technology-intensive testing in patients with syncope has a low diagnostic yield and consumes resources. The introduction of standards for the evaluation of syncope in the ED would be helpful.

Comparative yield of positive brain computed tomography after implementing the NICE or SIGN head injury guidelines in two equivalent urban populations

AIMS

To compare the yield of positive computed tomography (CT) brain examinations after the implementation of the National Institute for Clinical Excellence (NICE) or the Scottish Intercollegiate Guidance Network (SIGN) guidelines, in comparable urban populations in two teaching hospitals in England and Scotland.

MATERIALS AND METHODS

Four hundred consecutive patients presenting at each location following a head injury who underwent a CT examination of the head according to the locally implemented guidelines were compared. Similar matched populations were compared for indication and yield. Yield was measured according to (1) positive CT findings of the sequelae of trauma and (2) intervention required with anaesthetic or intensive care unit (ICU) support, or neurosurgery.

RESULTS

The mean ages of patients at the English and Scottish centres were 49.9 and 49.2 years, respectively. Sex distribution was 64.1% male and 66.4% male respectively. Comparative yield was 23.8 and 26.5% for positive brain scans, 3 and 2.75% for anaesthetic support, and 3.75 and 2.5% for neurosurgical intervention. Glasgow Coma Score (GCS) <13 (NICE) and GCS ≤ 12 and radiological or clinical evidence of skull fracture (SIGN) demonstrated the greatest statistical association with a positive CT examination.

CONCLUSION

In a teaching hospital setting, there is no significant difference in the yield between the NICE and SIGN guidelines. Both meet the SIGN standard of >10% yield of positive scans. The choice of guideline to follow should be at the discretion of the local institution. The indications GCS <13 and clinical or radiological evidence of a skull fracture are highly predictive of intracranial pathology, and their presence should be an absolute indicator for fast-tracking the management of the patient.

Management of traumatic head injuries in a rural Irish hospital: implications of the NICE guidelines

BACKGROUND

The NICE guidelines were published in 2003 in an effort to standardise the management of traumatic head injuries, and advise a CT brain in certain situations.

AIM

To evaluate the influence of the NICE guidelines on the management of head injuries in a county hospital.

METHODS

Complete clinical data were obtained for all patients with traumatic head injuries attending the ED of a county hospital from 2001 to 2005. Symptoms, examination details and outcome data were made available. The influence of the NICE guidelines on their management was then evaluated.

RESULTS

Application of the NICE guidelines to these patients would have resulted in a 56% increase in the rate of CT brains being performed. No patient who did not have a CT brain had an adverse outcome.

CONCLUSION

It is possible with limited resources and normal neurological observations that patients over the age of 65 can be managed safely.

Fixed negative charge and the Donnan effect: a description of the driving forces associated with brain tissue swelling and oedema

Cerebral oedema or brain tissue swelling is a significant complication following traumatic brain injury or stroke that can increase the intracranial pressure (ICP) and impair blood flow. Here, we have identified a potential driver of oedema: the negatively charged molecules fixed within cells. This fixed charge density (FCD), once exposed, could increase ICP through the Donnan effect. We have shown that metabolic processes and membrane integrity are required for concealing this FCD as slices of rat cortex swelled immediately (within 30 min) following dissection if treated with 2 deoxyglucose + cyanide (2DG+CN) or Triton X-100. Slices given ample oxygen and glucose, however, did not swell significantly. We also found that dead brain tissue swells and shrinks in response to changes in ionic strength of the bathing medium, which suggests that the Donnan effect is capable of pressurizing and swelling brain tissue. As predicted, a non-ionic osmolyte, 1,2 propanediol, elicited no volume change at 2000 x 10(-3) osmoles l(-1) (Osm). Swelling data were well described by triphasic mixture theory with the calculated reference state FCD similar to that measured with a 1,9 dimethylmethylene blue assay. Taken together, these data suggest that intracellular fixed charges may contribute to the driving forces responsible for brain swelling.