707 RESEARCH PRIORITIES FOR PREHOSPITAL CARE OF OLDER PATIENTS WITH INJURIES: SCOPING REVIEW

Introduction

The use of ambulance services by older patients with injuries increases within the impacts of ageing-related changes leading to adverse patient outcomes. There is increasing recognition of the importance of prehospital trauma care for older patients, but little systematic research to guide practice. We aimed to review the published evidence on prehospital trauma care for older patients, determine the scope of existing research and identify research gaps in the literature.

Methods

A systematic scoping review guided by the Arksey and O’Malley framework reported in line with the PRISMA-ScR checklist. A systematic search was conducted of Scopus, CINAHL, MEDLINE, PubMed and Cochrane library databases to identify articles published between (2001–2021) years. Inclusion and exclusion criteria were applied independently by two reviewers. Data were extracted, charted and summarised from eligible articles.

Results

65 studies were identified and reviewed, and 25 included. Five categories were identified: ‘field triage, “ageing impacts”, ‘decision-making’, ‘paramedic’ awareness’ and ‘paramedic’s behaviour’. Undertriage & overtriage (sensitivity & specificity) were commonly cited as poorly investigated field-triage subthemes. Ageing-related physiologic changes, comorbidities and polypharmacy were the most widely researched. Inaccurate decision-making and poor early identification of major injuries were identified as potentially influencing patient outcomes. More research is required into paramedic knowledge of geriatric care & ageing changes and the potential impact of paramedic care.

Conclusion

This is the first study reviewing the published evidence on prehospital trauma care for older patients and identifying research priorities for future research. This review has identified the prehospital triage for older trauma victims and studies of paramedic knowledge of older trauma care as key priorities. Investigating and understanding these can improve providing prehospital trauma care of older patients.

The DiPEP study: an observational study of the diagnostic accuracy of clinical assessment, D-dimer and chest x-ray for suspected pulmonary embolism in pregnancy and postpartum

Objective

To identify clinical features associated with pulmonary embolism (PE) diagnosis and determine the accuracy of decision rules and D‐dimer for diagnosing suspected PE in pregnant/postpartum women

Design

Observational cohort study augmented with additional cases.

Setting

Emergency departments and maternity units at eleven prospectively recruiting sites and maternity units in the United Kingdom Obstetric Surveillance System (UKOSS)

Population

324 pregnant/postpartum women with suspected PE and 198 pregnant/postpartum women with diagnosed PE

Methods

We recorded clinical features, elements of clinical decision rules, D‐dimer measurements, imaging results, treatments and adverse outcomes up to 30 days

Main outcome measures

Women were classified as having PE on the basis of imaging, treatment and adverse outcomes by assessors blind to clinical features and D‐dimer. Primary analysis was limited to women with conclusive imaging to avoid work‐up bias. Secondary analyses included women with clinically diagnosed or ruled out PE.

Results

The only clinical features associated with PE on multivariate analysis were age (odds ratio 1.06; 95% confidence interval 1.01–1.11), previous thrombosis (3.07; 1.05–8.99), family history of thrombosis (0.35; 0.14–0.90), temperature (2.22; 1.26–3.91), systolic blood pressure (0.96; 0.93–0.99), oxygen saturation (0.87; 0.78–0.97) and PE‐related chest x‐ray abnormality (13.4; 1.39–130.2). Clinical decision rules had areas under the receiver‐operator characteristic curve ranging from 0.577 to 0.732 and no clinically useful threshold for decision‐making. Sensitivities and specificities of D‐dimer were 88.4% and 8.8% using a standard threshold and 69.8% and 32.8% using a pregnancy‐specific threshold.

Conclusions

Clinical decision rules and D‐dimer should not be used to select pregnant or postpartum women with suspected PE for further investigation. Clinical features and chest x‐ray appearances may have counter‐intuitive associations with PE in this context.

Tweetable abstract

Clinical decision rules and D‐dimer are not helpful for diagnosing pregnant/postpartum women with suspected PE

Clinical decision rules and D‐dimer are not helpful for diagnosing pregnant/postpartum women with suspected PE.

'Seizure First Aid Training' for people with epilepsy who attend emergency departments, and their family and friends: study protocol for intervention development and a pilot randomised controlled trial

INTRODUCTION

People with chronic epilepsy (PWE) often make costly but clinically unnecessary emergency department (ED) visits. Offering them and their carers a self-management intervention that improves confidence and ability to manage seizures may lead to fewer visits. As no such intervention currently exists, we describe a project to develop and pilot one.

METHODS AND ANALYSIS

To develop the intervention, an existing group-based seizure management course that has been offered by the Epilepsy Society within the voluntary sector to a broader audience will be adapted. Feedback from PWE, carers and representatives from the main groups caring for PWE will help refine the course so that it addresses the needs of ED attendees. Its behaviour change potential will also be optimised. A pilot randomised controlled trial will then be completed. 80 PWE aged ≥16 who have visited the ED in the prior 12 months on ≥2 occasions, along with one of their family members or friends, will be recruited from three NHS EDs. Dyads will be randomised to receive the intervention or treatment as usual alone. The proposed primary outcome is ED use in the 12 months following randomisation. For the pilot, this will be measured using routine hospital data. Secondary outcomes will be measured by patients and carers completing questionnaires 3, 6 and 12 months postrandomisation. Rates of recruitment, retention and unblinding will be calculated, along with the ED event rate in the control group and an estimate of the intervention's effect on the outcome measures.

ETHICS AND DISSEMINATION

Ethical approval: NRES Committee North West-Liverpool East (Reference number 15/NW/0225). The project's findings will provide robust evidence on the acceptability of seizure management training and on the optimal design of a future definitive trial. The findings will be published in peer-reviewed journals and presented at conferences.

TRIAL REGISTRATION NUMBER

ISRCTN13 871 327.

The clinical and diagnostic performance characteristics of the high sensitivity Abbott cardiac troponin I assay

OBJECTIVES

The aim of this study is to determine the imprecision profile, 99th percentile and diagnostic efficiency of a new high sensitivity cardiac troponin I (cTnI) assay.

METHODS

Total imprecision was assessed by following CLSI protocol EP15-A.14. Serum pools prepared from sera of known high cardiac troponin concentrations were adjusted by dilution with serum considered to be troponin free. Determination of the 99th-percentile reference value examined a fully characterized population that had undergone non-invasive cardiac imaging. Diagnostic accuracy utilised samples from the point of care arm of the RATPAC trial (Randomised Assessment of Treatment using Panel Assay of Cardiac markers), set in the emergency departments of six hospitals. Blood samples were taken on admission and 90min from admission. Diagnosis was based on the universal definition of myocardial infarction utilising laboratory measurements of cardiac troponin performed at the participating sites together with measurements performed in a core laboratory and compared by construction of receiver operator characteristic curves.

RESULTS

Total imprecision was 4%-12.1% with 10% CV of 7ng/L. cTnI was measureable in 99.5% of the samples. Troponin values were influenced by gender but not by age. The 99th percentile was 14.8ng/L (18.1 males, 8.6 females). Progressive filtering of the population reduced the 99th percentile. For the diagnosis of MI on admission the area under the curve was 0.92, statistically indistinguishable from four other assays studied (0.90-0.94).

CONCLUSION

The analytical performance of the new assay meets the criteria for a high sensitivity troponin assay.

Illness representations, psychological distress and non-cardiac chest pain in patients attending an emergency department

OBJECTIVE

Many patients who attend an emergency department (ED) with chest pain receive a diagnosis of non-cardiac chest pain (NCCP), and often suffer poor psychological outcomes and continued pain. This study assessed the role of illness representations in explaining psychological distress and continued chest pain in patients attending an ED.

METHODS

ED NCCP patients (N = 138) completed measures assessing illness representations, anxiety, depression and quality of life (QoL) at baseline, and chest pain at one month.

RESULTS

Illness representations explained significant amounts of the variance in anxiety (Adj. R² = .38), depression (Adj. R² = .18) and mental QoL (Adj. R² = .36). A belief in psychological causes had the strongest associations with outcomes. At one month, 28.7% of participants reported experiencing frequent pain, 13.2% infrequent pain and 58.1% no pain. Anxiety, depression and poor QoL, but not illness representations, were associated with continued chest pain.

CONCLUSIONS

The findings suggest that (i) continued chest pain is related to psychological distress and poor QoL, (ii) interventions should be aimed at reducing psychological distress and improving QoL and (iii) given the associations between perceived psychological causes and psychological distress/QoL, NCCP patients in the ED might benefit from psychological therapies to manage their chest pain.

Hospital characteristics affecting potentially avoidable emergency admissions: national ecological study

Some emergency admissions can be avoided if acute exacerbations of health problems are managed by emergency and urgent care services without resorting to admission to a hospital bed. In England, these services include hospitals, emergency ambulance, and a range of primary and community services. The aim was to identify whether characteristics of hospitals affect potentially avoidable emergency admission rates. An age-sex adjusted rate of admission for 14 conditions rich in avoidable emergency admissions was calculated for 129 hospitals in England for 2008-2011. Twenty-two per cent (3,273,395/14,998,773) of emergency admissions were classed as potentially avoidable, with threefold variation between hospitals. Explanatory factors of this variation included those which hospital managers could not control (demand for hospital emergency departments) and those which they could control (supply in terms of numbers of acute beds in the hospital, and management of non-emergency and emergency patients within the hospital). Avoidable admission rates were higher for hospitals with higher emergency department attendance rates, higher numbers of acute beds per 1000 catchment population and higher conversion rates from emergency department attendance to admission. Hospital managers may be able to reduce avoidable emergency admissions by reducing supply of acute beds and conversion rates from emergency department attendance.

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

AIM

To estimate the cost-effectiveness of diagnostic management strategies for children with minor head injury and identify an optimal strategy.

METHODS

A probabilistic decision analysis model was developed to estimate the costs and quality-adjusted life years (QALYs) accrued by each of six potential management strategies for minor head injury, including a theoretical 'zero option' strategy of discharging all patients home without investigation. The model took a lifetime horizon and the perspective of the National Health Service.

RESULTS

The optimal strategy was based on the Children's Head injury Algorithm for the prediction of Important Clinical Events (CHALICE) rule, although the costs and outcomes associated with each strategy were broadly similar.

CONCLUSIONS

Liberal use of CT scanning based on a high sensitivity decision rule is not only effective but also cost saving, with the CHALICE rule being the optimal strategy, although there is some uncertainty in the results. Incremental changes in the costs and QALYs are very small when all selective CT strategies are compared. The estimated cost of caring for patients with brain injury worsened by delayed treatment is very high compared with the cost of CT scanning. This analysis suggests that all hospitals receiving children with minor head injury should have unrestricted access to CT scanning for use in conjunction with evidence-based guidelines.

Randomised Assessment of Treatment using Panel Assay of Cardiac markers--Contemporary Biomarker Evaluation (RATPAC CBE)

OBJECTIVES

To test the diagnostic accuracy for detecting an acute myocardial infarction (AMI) using highly sensitive troponin assays and a range of new cardiac biomarkers of plaque destabilisation, myocardial ischaemia and necrosis; to test the prognostic accuracy for detecting adverse cardiac events using highly sensitive troponin assays and this range of new cardiac biomarkers; and to estimate the cost-effectiveness of using highly sensitive troponin assays or this range of new cardiac biomarkers instead of an admission and 10- to 12-hour troponin measurement.

DESIGN

Substudy of the point-of-care arm of the RATPAC (Randomised Assessment of Treatment using Panel Assay of Cardiac markers) trial.

SETTING

The emergency departments of six hospitals.

PARTICIPANTS

Prospective admissions with chest pain and a non-diagnostic electrocardiogram randomised to point-of-care assessment or conventional management.

INTERVENTIONS

Blood samples taken on admission and 90 minutes from admission for measurement of cardiac markers [cardiac troponin I (cTnI), myoglobin and creatine kinase MB isoenzyme (CK-MB)] by point-of-care testing. An additional blood sample was taken at admission and 90 minutes from admission for analysis of high-sensitivity cTnI (two methods) and cardiac troponin T (cTnT), myoglobin, heart-type fatty acid-binding protein (H-FABP), copeptin and B-type natriuretic peptide (NTproBNP).

MAIN OUTCOME MEASURES

1. Diagnostic accuracy compared with the universal definition of myocardial infarction utilising laboratory measurements of cardiac troponin performed at the participating sites together with measurements performed in a core laboratory. 2. Ability of biomarker measurements to predict major adverse cardiac events (death, non-fatal AMI, emergency revascularisation or hospitalisation for myocardial ischaemia) at 3 months' follow-up. 3. Comparison of incremental cost per quality-adjusted life-year (QALY) of different biomarker measurement strategies for the diagnosis of myocardial infarction.

RESULTS

Samples were available from 850 out of 1132 patients enrolled in the study. Measurement of admission myoglobin [area under the curve (AUC) 0.76] and CK-MB (AUC 0.84) was diagnostically inferior and did not add to the diagnostic efficiency of cTnI (AUC 0.90-0.94) or cTnT (AUC 0.92) measurement on admission. Simultaneous measurement of H-FABP and cTnT or cTnI did improve admission diagnostic sensitivity to 0.78-0.92, but only to the same level as that achieved with troponin measured on admission and at 90 minutes from admission (0.78-0.95). Copeptin (AUC 0.62) and NTproBNP (AUC 0.85) measured on admission were not useful as diagnostic markers. As a prognostic marker, troponin measured on admission using a high-sensitivity assay (AUC 0.73-0.83) was equivalent to NTproBNP measurement (AUC 0.77) on admission, but superior to copeptin measurement (AUC 0.58). From modelling, 10-hour troponin measurement is likely to be cost-effective compared with rapid rule-out strategies only if a £30,000 per QALY threshold is used and patients can be discharged as soon as a negative result is available.

CONCLUSIONS

The measurement of high-sensitivity cardiac troponin is the best single marker in patients presenting with chest pain. Additional measurements of myoglobin or CK-MB are not clinically effective or cost-effective. The optimal timing for measurement of cardiac troponin remains to be defined. Copeptin measurement is not recommended. H-FABP requires further investigation before it can be recommended for simultaneous measurement with high-sensitivity troponin in patients with acute chest pain.

TRIAL REGISTRATION

ISRCTN37823923.

FUNDING

This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 17, No. 15. See the HTA programme website for further project information.

Systematic review, meta-analysis and economic modelling of diagnostic strategies for suspected acute coronary syndrome

BACKGROUND

Current practice for suspected acute coronary syndrome (ACS) involves troponin testing 10-12 hours after symptom onset to diagnose myocardial infarction (MI). Patients with a negative troponin can be investigated further with computed tomographic coronary angiography (CTCA) or exercise electrocardiography (ECG).

OBJECTIVES

We aimed to estimate the diagnostic accuracy of early biomarkers for MI, the prognostic accuracy of biomarkers for major adverse cardiac adverse events (MACEs) in troponin-negative patients, the diagnostic accuracy of CTCA and exercise ECG for coronary artery disease (CAD) and the prognostic accuracy of CTCA and exercise ECG for MACEs in patients with suspected ACS. We then aimed to estimate the cost-effectiveness of using alternative biomarker strategies to diagnose MI, and using biomarkers, CTCA and exercise ECG to risk-stratify troponin-negative patients.

DATA SOURCES

We searched MEDLINE, MEDLINE In-Process & Other Non-Indexed Citations; Cumulative Index of Nursing and Allied Health Literature (CINAHL), EMBASE, Web of Science, Cochrane Central Database of Controlled Trials (CENTRAL), Cochrane Database of Systematic Reviews (CDSR), NHS Database of Abstracts of Reviews of Effects (DARE) and the Health Technology Assessment database from 1985 (CTCA review) or 1995 (biomarkers review) to November 2010, reviewed citation lists and contacted experts to identify relevant studies.

REVIEW METHODS

Diagnostic studies were assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) tool and prognostic studies using a framework adapted for the project. Meta-analysis was conducted using bayesian Markov chain Monte Carlo simulation. We developed a decision-analysis model to evaluate the cost-effectiveness of alternative biomarker strategies to diagnose MI, and the cost-effectiveness of biomarkers, CTCA or exercise ECG to risk-stratify patients with a negative troponin. Strategies were applied to a theoretical cohort of patients with suspected ACS. Cost-effectiveness was estimated as the incremental cost per quality-adjusted life-year (QALY) of each strategy compared with the next most effective, taking a health-service perspective and a lifetime horizon.

RESULTS

Sensitivity and specificity (95% predictive interval) were 77% (29-96%) and 93% (46-100%) for troponin I, 80% (33-97%) and 91% (53-99%) for troponin T (99th percentile threshold), 81% (50-95%) and 80% (26-98%) for quantitative heart-type fatty acid-binding protein (H-FABP), 68% (11-97%) and 92% (20-100%) for qualitative H-FABP, 77% (19-98%) and 39% (2-95%) for ischaemia-modified albumin and 62% (35-83%) and 83% (35-98%) for myoglobin. CTCA had 94% (61-99%) sensitivity and 87% (16-100%) specificity for CAD. Positive CTCA and positive-exercise ECG had relative risks of 5.8 (0.6-24.5) and 8.0 (2.3-22.7) for MACEs. In most scenarios in the economic analysis presentation, high-sensitivity troponin measurement was the most effective strategy with an incremental cost-effectiveness ratio (ICER) of less than the £20,000-30,000/QALY threshold (ICER £7487-17,191/QALY). CTCA appeared to be the most cost-effective strategy for patients with a negative troponin, with an ICER of £11,041/QALY. However, when a lower MACE rate was assumed, CTCA had a high ICER (£262,061/QALY) and the no-testing strategy was optimal.

LIMITATIONS

There was substantial variation between the primary studies and heterogeneity in their results. Findings of the economic model were dependent on assumptions regarding the value of detecting and treating positive cases.

CONCLUSIONS

Although presentation troponin has suboptimal sensitivity, measurement of a 10-hour troponin level is unlikely to be cost-effective in most scenarios compared with a high-sensitivity presentation troponin. CTCA may be a cost-effective strategy for troponin-negative patients, but further research is required to estimate the effect of CTCA on event rates and health-care costs.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

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.

Diagnostic management strategies for adults and children with minor head injury: a systematic review and an economic evaluation

BACKGROUND

Patients with minor head injury [Glasgow Coma Scale (GCS) score 13-15] have a small but important risk of intracranial injury (ICI) that requires early identification and neurosurgical treatment. Diagnostic assessment can use either a clinical decision rule or unstructured assessment of individual clinical features to identify those who are at risk of ICI and in need of computerised tomography (CT) scanning and/or hospital admission. Selective use of CT investigations helps minimise unnecessary radiation exposure and resource use, but can lead to missed opportunities to provide early treatment for ICI.

OBJECTIVES

To determine the diagnostic accuracy of decision rules, individual clinical characteristics, skull radiography and biomarkers, and the clinical effectiveness and cost-effectiveness of diagnostic management strategies for minor head injury (MHI).

DATA SOURCES

Several electronic databases [including MEDLINE, MEDLINE In-Process & Other Non-Indexed Citations, Cumulative Index to Nursing and Allied Health Literature (CINAHL), EMBASE and The Cochrane Library] were searched from inception to April 2009 (updated searches to March 2010 were conducted on the MEDLINE databases only). Searches were supplemented by hand-searching relevant articles (including citation searching) and contacting experts in the field. For each of the systematic reviews the following studies were included (1) cohort studies of patients with MHI in which a clinical decision rule or individual clinical characteristics (including biomarkers and skull radiography) were compared with a reference standard test for ICI or need for neurosurgical intervention and (2) controlled trials comparing alternative management strategies for MHI.

REVIEW METHODS

Study quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) tool (for the assessment of diagnostic accuracy) or criteria recommended by the Effective Practice and Organisation of Care Review Group (for the assessment of management practices). Where sufficient data existed, a meta-analysis was undertaken to generate pooled estimates of diagnostic parameters. A decision-analysis model was developed using Simul8 2008 Professional software (Simul8 Corporation, Boston, MA, USA) to estimate the costs and quality-adjusted life-years (QALYs) accrued by management strategies for MHI. The model took a lifetime horizon and NHS perspective. Estimates of the benefits of early treatment, harm of radiation exposure and long-term costs were obtained through literature reviews. Initial analysis was deterministic, but probabilistic sensitivity analysis was also performed. Secondary analyses were undertaken to explore the trade-off between sensitivity and specificity in diagnostic strategies and to determine the cost-effectiveness of scenarios involving hospital admission.

RESULTS

The literature searches identified 8003 citations. Of these, 93 full-text papers were included for the assessment of diagnostic accuracy and one for the assessment of management practices. The quality of studies and reporting was generally poor. The Canadian CT Head Rule (CCHR) was the most widely validated adult rule, with sensitivity of 99-100% and 80-100% for neurosurgical and any ICI, respectively (high- or medium-risk criteria), and specificity of 39-51%. Rules for children had high sensitivity and acceptable specificity in derivation cohorts, but limited validation. Depressed, basal or radiological skull fracture and post-traumatic seizure (PTS) [positive likelihood ratio (PLR) > 10]; focal neurological deficit, persistent vomiting, decrease in GCS and previous neurosurgery (PLR 5-10); and fall from a height, coagulopathy, chronic alcohol use, age > 60 years, pedestrian motor vehicle accident (MVA), any seizure, undefined vomiting, amnesia, GCS < 14 and GCS < 15 (PLR 2-5) increased the likelihood of ICI in adults. Depressed or basal skull fracture and focal neurological deficit (PLR > 10), coagulopathy, PTS and previous neurosurgery (PLR 5-10), visual symptoms, bicycle and pedestrian MVA, any seizure, loss of consciousness, vomiting, severe or persistent headache, amnesia, GCS < 14, GCS < 15, intoxication and radiological skull fracture (PLR 2-5) increased the likelihood of ICI in children. S100 calcium-binding protein B had pooled sensitivity of 96.8% [95% highest-density region (HDR) 93.8% to 98.6%] and specificity of 42.5% (95% HDR 31.0% to 54.2%). The only controlled trial showed that early CT and discharge is cheaper and at least as effective as hospital admission. Economic analysis showed that selective CT use dominated 'CT all' and 'discharge all' strategies. The optimal strategies were the CCHR (adults) and the CHALICE (Children's Head injury Algorithm for the prediction of Important Clinical Events) or NEXUS II (National Emergency X-Radiography Utilization Study II) rule (children). The sensitivity and specificity of the CCHR (99% and 47%, respectively) represented an appropriate trade-off of these parameters. Hospital admission dominated discharge home for patients with non-neurosurgical injury, but cost £39 M per QALY for clinically normal patients with a normal CT.

CONCLUSIONS

The CCHR is widely validated and cost-effective for adults. Decision rules for children appear cost-effective, but need further validation. Hospital admission is cost-effective for patients with abnormal, but not normal, CT. The main research priorities are to (1) validate decision rules for children; (2) determine the prognosis and treatment benefit for non-neurosurgical injuries; (3) evaluate the use of S100B alongside a validated decision rule; (4) evaluate the diagnosis and outcomes of anticoagulated patients with MHI; and (5) evaluate the implementation of guidelines, clinical decision rules and diagnostic strategies. Formal expected value of sample information analysis would be recommended to appraise the cost-effectiveness of future studies.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Diuretic, opiate and nitrate use in severe acidotic acute cardiogenic pulmonary oedema: analysis from the 3CPO trial

BACKGROUND

Drug treatments for acute cardiogenic pulmonary oedema (ACPO) have not been rigorously evaluated and recent observational data suggests some agents are related to poorer outcome.

AIM

We aimed to examine the effect of treatment with diuretics, nitrates and opiates on 7-day mortality, acidosis and respiratory distress in UK Emergency Department (ED) patients with severe acidotic pulmonary oedema.

DESIGN

Analysis of data from the 3CPO trial; a multicentre randomized controlled trial.

METHODS

Data were analysed from patients recruited with severe acidotic pulmonary oedema to the 3CPO trial in 26 UK EDs between 2003 and 2007. The effects of these treatments on 7-day mortality, improvement in acidosis (pH change between baseline and 1 h) and improvement in respiratory distress (patient measured breathlessness using a Visual Analogue Score between baseline and 1 h) were tested using univariate logistic regression analysis, and a regression model used to adjust for confounding baseline differences.

RESULTS

Nitrates were given to 947/1048 (90.4%) patients, diuretics to 934/1049 (89.0%) patients and opiates to 541/1052 patients (51.4%). Adjusted analysis showed that opiate treatment was associated with less improvement in acidosis [difference in improvement in pH -0.022, 95% confidence interval (CI) -0.014 to -0.030, P < 0.001], but no difference in mortality or improvement in respiratory distress. We found no evidence that nitrate or diuretic use were associated with any difference in mortality, improvement in acidosis or respiratory distress.

CONCLUSION

Opiate use is associated with less improvement in acidosis during initial treatment and may attenuate effective treatment of severe acidotic ACPO.

Magnesium sulphate in the treatment of acute asthma: evaluation of current practice in adult emergency departments

BACKGROUND

A recent meta-analysis showed that intravenous and nebulised magnesium sulphate have similar levels of evidence to support their use in the treatment of acute asthma in adults. This consisted of weak evidence of effect on respiratory function and hospital admissions, with wide confidence intervals ranging from no effect to significant positive effects. Current BTS/SIGN guidelines suggest an equivocal role for intravenous magnesium sulphate and no role for nebulised magnesium sulphate. A study was performed to assess what emergency physicians currently do in their management of acute asthma.

METHOD

A postal survey was undertaken of all adult emergency departments within the UK. A structured questionnaire was sent to all clinical leads in emergency medicine about their current usage of both intravenous and nebulised magnesium sulphate in the treatment of acute asthma.

RESULTS

180 of the 251 emergency departments in the UK responded (72%). Magnesium sulphate was used in 93%, mostly because it was expected to relieve breathlessness (70%) or reduce HDU/ITU admissions (51%). It was predominantly given to those patients with acute severe asthma (84%) and life-threatening exacerbations (87%), with most stating they would give the drug if there was no response to repeated nebulisers (68%). In comparison, nebulised magnesium sulphate was only used in two emergency departments (1%). The main reason for not administering the drug via a nebuliser was insufficient evidence (51%).

CONCLUSIONS

Intravenous magnesium sulphate is widely used for acute asthma, usually for patients with severe or life-threatening asthma who have not responded to initial treatment. Nebulised magnesium sulphate, by contrast, is hardly used at all. The use of intravenous magnesium sulphate is more extensive than current guidelines or available evidence would appear to support.

Accessibility versus confidentiality of information in the emergency department

INTRODUCTION

In the emergency department (ED), clinicians can benefit greatly from having access to information at the point of care. It has been suggested that using computerised information systems could improve the accessibility of information. However, making information accessible, while maintaining confidentiality, is one of the main challenges of implementing information systems. This article presents the ED staff perspectives about the accessibility and confidentiality of information in the ED.

METHOD

The authors undertook a qualitative study in March-April 2007. Data were collected using in-depth semi-structured interviews with the ED staff of an ED located in Northern England. In total, 34 interviews were conducted and transcribed verbatim. Data were analysed using framework analysis.

RESULTS

The results showed that the ED staff had role-based access to the current information systems, and these systems met only a small part of their information needs. As a result, different sources were used to get access to the needed information. Although the ED staff believed that improving the accessibility of information could be helpful in emergency care services, there were concerns about the confidentiality of information. The confidentiality of information could be threatened--for example, by sharing passwords, misusing patient information or by unauthorised staff having access to patient information.

CONCLUSION

To design a system, the accessibility and confidentiality of information should be addressed in parallel. A balance between these two is needed, as the failure of each of these may negatively influence the use of the system.

Hospital admissions with head injury following publication of NICE guidance

BACKGROUND

A recent update suggested that the National Institute for Health and Clinical Excellence (NICE) guidance on head injury had led to safe early discharge, evidence of a reduction in the numbers of admitted patients and cost savings in some centres. The aim of this study was to use national Hospital Episodes Statistics (HES) data to determine whether admissions with head injury have changed since the NICE guidance was introduced.

METHODS

HES data coded as S00-S09 "Injuries to the head" from 1998-9 to 2006-7 were examined for admissions, age and length of stay.

RESULTS

Admissions rates did not change markedly until 2003 when the NICE head injury guidelines were issued. From 2003, admissions increased for all adult age groups but not for children. Mean length of stay remained constant between 1998 and 2007, so bed days increased in proportion to admission rates.

CONCLUSION

Adult head injury admissions in England have increased markedly since the introduction of the NICE guidelines. Given that there is little evidence that hospital admission is beneficial for patients with minor head injury, NICE head injury guidance appears to have failed to promote cost effective care.

Intravenous and nebulised magnesium sulphate for acute asthma: systematic review and meta-analysis

OBJECTIVES

To estimate the effect of intravenous and nebulised magnesium sulphate upon hospital admissions and pulmonary function in adults and children with acute asthma.

METHODS

We undertook a systematic review and meta-analysis of randomised and quasi-randomised trials of intravenous or nebulised magnesium sulphate in acute asthma. Trials were identified by searches of the electronic literature, relevant journal websites and conference proceedings, and contact with authors and experts. Data were pooled using random effects meta-analysis of the relative risk (RR) of hospital admission and the standardised mean difference (SMD) in pulmonary function.

RESULTS

24 studies (15 intravenous, 9 nebulised) incorporating 1669 patients were included. Intravenous treatment was associated in adults with weak evidence of an effect upon respiratory function (SMD 0.25, 95% confidence interval (CI) -0.01 to 0.51; p = 0.05), but no significant effect upon hospital admission (RR 0.87, 95% CI 0.70 to 1.08; p = 0.22), and in children with a significant effect upon respiratory function (SMD 1.94, 95% CI 0.80 to 3.08; p<0.001) and hospital admission (RR 0.70, 95% CI 0.54 to 0.90; p = 0.005). Nebulised treatment was associated in adults with weak evidence of an effect upon respiratory function (SMD 0.17, 95% CI -0.02 to 0.36; p = 0.09), and hospital admission (RR 0.68, 95% CI 0.46 to 1.02; p = 0.06), and in children with no significant effect upon respiratory function (SMD -0.26, 95% CI -1.49 to 0.98; p = 0.69) or hospital admission (RR 2.0, 95% CI 0.19 to 20.93; p = 0.56).

CONCLUSION

Intravenous magnesium sulphate appears to be an effective treatment in children. Further trials are needed of intravenous and nebulised magnesium sulphate in adults and nebulised magnesium sulphate in children.

The value of clinical features in the diagnosis of acute pulmonary embolism: systematic review and meta-analysis

BACKGROUND

Clinical assessment of patients with suspected pulmonary embolus (PE) is used to estimate the probability of PE and determine what (if any) diagnostic testing is required.

AIM

We aimed to estimate the diagnostic value of individual clinical features used to determine the pre-test probability of acute PE.

DESIGN

Systematic review and meta-analysis.

METHODS

We searched electronic databases (1966 to May 2007) and the bibliographies of retrieved articles for any article that reported the diagnostic performance of clinical features compared to a reference standard diagnostic test in patients with suspected acute pulmonary embolism. Likelihood ratios were calculated for each feature and pooled using a random effects model, as implemented by MetaDiSc statistical software.

RESULTS

We identified 18 studies for inclusion with a total of 5997 patients. The most useful features (pooled likelihood ratio) for ruling in PE were syncope (2.38), shock (4.07), thrombophlebitis (2.20), current DVT (2.05), leg swelling (2.11), sudden dyspnoea (1.83), active cancer (1.74), recent surgery (1.63), haemoptysis (1.62) and leg pain (1.60); while the most useful features for ruling out PE were the absence of sudden dyspnoea (0.430), any dyspnoea (0.521) and tachypnea (0.561). All other clinical features had likelihood ratios near to one. Many of the analyses involved pooling results that had significant heterogeneity, so these estimates should be used with caution.

CONCLUSION

Individual clinical features only slightly raise or lower the probability of PE. In isolation, they have limited diagnostic value and none can be used to rule in or rule out PE without further testing.

Safe discharge: an irrational, unhelpful and unachievable concept

Emergency doctors often decide whether to advise hospital admission or discharge by assessing whether a decision to discharge home is considered safe. This implies that hospital admission may be recommended on the basis of exceeding an arbitrarily defined risk of adverse outcome, rather than weighing the potential benefits, risks and costs of hospital admission. This approach is likely to lead to irrational decision making, unnecessary hospitalisation and unrealistic expectations regarding risk. Instead of using the concept of a safe discharge, we should take a more rational approach to decision making, weighing the benefits, risks and costs of hospitalisation against a default option of discharge home. Hospital admission should be recommended only if the expected benefits outweigh the risks and can be accrued at an acceptable cost. Guidelines should be developed using this approach and used to promote and support rational decision making.