Trends in head injury outcome from 1989 to 2003 and the effect of neurosurgical care: an observational study.

BACKGROUND: Case fatality rates after all types of blunt injury have not improved since 1994 in England and Wales, possibly because not all patients with severe head injury are treated in a neurosurgical centre. Our aims were to investigate the case fatality trends in major trauma patients with and without head injury, and to establish the effect of neurosurgical care on mortality after severe head injury. METHODS: We analysed prospectively collected data from the Trauma Audit and Research Network database for patients presenting between 1989 and 2003. Mortality and odds of death adjusted for case mix were compared for patients with and without head injury, and for those treated in a neurosurgical versus a non-neurosurgical centre. FINDINGS: Patients with head injury (n=22,216) had a ten-fold higher mortality and showed less improvement in the adjusted odds of death since 1989 than did patients without head injury (n=154,231). 2305 (33%) of patients with severe head injury (presenting between 1996 and 2003) were treated only in non-neurosurgical centres; such treatment was associated with a 26% increase in mortality and a 2.15-fold increase (95% CI 1.77-2.60) in the odds of death adjusted for case mix compared with patients treated at a neurosurgical centre. INTERPRETATION: Since 1989 trauma system changes in England and Wales have delivered greater benefit to patients without head injury. Our data lend support to current guidelines, suggesting that treatment in a neurosurgical centre represents an important strategy in the management of severe head injury.

Tryptophan fluorescence of (Na+ + K+)-ATPase as a tool for study of the enzyme mechanism.

1. The protein fluorescence intensity of (Na+ + K+)-ATPase is enhanced following binding of K+ at low concentrations. The properties of the response suggest that one or a few tryptophan residues are affected by a conformational transition between the K-bound form E2 . (K) and a Na-bound form E1 . Na. 2. The rate of the conformational transition E2 . (K) leads to E . Na has been measured with a stopped-flow fluorimeter by exploiting the difference in fluorescence of the two states. In the absence of ATP the rate is very slow, but it is greatly accelerated by binding of ATP to a low affinity site. 3. Transient changes in tryptophan fluorescence accompany hydrolysis of ATP at low concentrations, in media containing Mg2+, Na+ and K+. The fluorescence response reflects interconversion between the initial enzyme conformation, E1 . Na and the steady-state turnover intermediate E2 . (K). 4. The phosphorylated intermediate, E2P can be detected by a fluorescence increase accompanying hydrolysis of ATP in media containing Mg2+ and Na+ but no K+. 5. The conformational states and reaction mechanism of the (Na+ + K+)-ATPase are discussed in the light of this work. The results permit a comparison of the behaviour of the enzyme at both low and high nucleotide concentrations.

Elementary steps of the (Na+ + K+)-ATPase mechanism, studied with formycin nucleotides.

1. Formycin triphosphate (FTP), a fluorescent analogue of ATP, is a substrate for (Na+ + K+)-ATPase (ATP phosphohydrolase, EC 3.6.1.3), with properties similar to those of ATP. 2. FTP and formycin diphosphate (FDP) bind to the enzyme with high affinity and, on binding, the nucleotide fluorescence is enhanced 3-4-fold. It is therefore possible, with a stopped-flow fluorimeter, to measure the rates of binding and release of FTP and FDP under conditions in which turnover does not occur. 3. When the enzyme-FTP complex is exposed to conditions permitting turnover (Mg2+, Na+ +/- K+), changes in fluorescence occur which can be explained by supposing that they reflect the interconversion of states with or without bound nucleotides. A rapid fall in fluorescence, that we attribute to the rapid release of FDP from newly phosphorylated enzyme, is followed by a steady state in which low fluorescence suggests that little nucleotide is bound. Eventually, exhaustion of FTP allows rebinding of FDP to the enzyme, which is signalled by a rise in fluorescence. 4. The estimated rate of FDP release from newly formed phosphoenzyme is unaffected by the presence of K+ (0-2 mM) or the concentration of FTP (1-20 micron). 5. Experiments with [gamma-32P]FTP show that about 1 mol of 32P is incorporated per mol of enzyme. The rate of phosphorylation of the enzyme by [gamma-32P]FTP has been measured with a rapid-mixing-and-quenching apparatus. 6. Kinetic data from the fluorescence and phosphorylation experiments show that the behaviour of the enzyme, at least at the low nucleotide concentrations employed, is consistent with the Albers-Post model, and is difficult to reconcile with models in which K+ acts at or before the step in which FDP is released during turnover.

Conformational transitions between Na+-bound and K+-bound forms of (Na+ + K+)-ATPase, studied with formycin nucleotides.

1. Fluorescence measurements have shown that formycin triphosphate (FTP) or formycin diphosphate (FDP) bound to (Na+ + K+)-ATPase (ATP phosphohydrolase, EC 3.6.1.3) in Na+-containing media can be displaced by the following ions (listed in order of effectiveness): Tl+, K+, Rb+, NH4+, Cs+. 2. The differences between the nucleotide affinities displayed by the enzyme in predominantly Na+ and predominantly K+ media in the absence of phosphorylation, are thought to reflect changes in enzyme conformation. These changes can therefore be monitored by observing the changes in fluorescence that accompany net binding or net release of formycin nucleotides. 3. The transition from a K+-bound form (E2-(K)) to an Na+-bound form (E1-Na) is remarkably slow at low nucleotide concentrations, but is accelerated if the nucleotide concentration is increased. This suggests that the binding of nucleotide to a low-affinity site on E2-(K) accelerates its conversion to E1-Na; it supports the hypothesis that during the normal working of the pump, ATP, acting at a low affinity site, accelerates the conversion of dephosphoenzyme, newly formed by K+-catalysed hydrolysis of E2P, to a form in which it can be phosphorylated in the presence of Na+. 4. The rate of the reverse transformation, E1-Na to E2-(K), varies roughly linearly with the K+ concentration up to the highest concentration at which the rate can be measured (15 mM). Since much lower concentrations of K+ are sufficient to displace the equilibrium to the K-form, we suggest that the sequence of events is: (i) combination of K+ with low affinity (probably internal) binding sites, followed by (ii) spontaneous conversion of the enzyme to a form, E2-(K), containing occluded K+. 5. Mg2+ or oligomycin slows the rate of conversion of E1-Na to E2-(K) but does not significantly affect the rate of conversion of E2-(K) to E1-Na. 6. In the light of these and previous findings, we propose a model for the sodium pump in which conformational changes alternate with trans-phosphorylations, and the inward and outward fluxes of both Na+ and K+ each involve the transfer of a phosphoryl group as well as a change in conformation between E1 and E2 forms of the enzyme or phosphoenzyme.

A system for measuring the severity of temporary and permanent disability after injury.

500 patients have been questioned about activities of daily living and mobility 4 and 26 weeks after injury in order to assess the extent of temporary and permanent disability following minor and major trauma. Only those who sustained single injuries have been assessed, resulting in a relatively small number of serious injuries in the sample. In other respects, the population is representative of the daytime attendance at a busy emergency department. Most patients sustained injuries with an Abbreviated Injury Scale (AIS) of 1 or 2 (96%); it is clear that the AIS is unable to distinguish between most small injuries. Assessment was by interview. Although subjective, this has produced results that have face validity and discriminate between a wide variety of injuries. The methodology may be useful in the development of a "disability score," but much more data will be required before this can be achieved.

Mild head injury--a positive approach to management.

It is estimated that 1.4 million patients each year attend Accident and Emergency (A&E) departments in the UK with a head injury. The vast majority are, in retrospect, diagnosed as a 'mild' injury. There is evidence to suggest that many develop short term morbidity and some long term problems. The incidence is unknown. Early recognition and treatment many hasten recovery. A national postal survey of A&E departments revealed a general unawareness for this morbidity. Written advice given to patients on discharge from the departments was exclusively concerned with the symptoms expected if serious complications developed. A description of the common symptoms of fatigue, poor memory and concentration were not given to the patients in a written format. Arrangements for follow up are, in the majority of hospitals, unstructured. We recommend a positive approach to the management and follow up of mild head injury. This should recognize the common problems experienced by these patients and cater for their needs. More interest and research is required into this aspect of head injury.

Placement of electrodes for defibrillation--a review of the evidence.

Defibrillation is the only reliable treatment for ventricular fibrillation. Its success depends on the passage of an adequate current through the chest rather than on the administration of a preset energy. The final determinant of both efficacy and cellular damage is myocardial current density. Therefore, the current should be evenly distributed with an average value that exceeds the defibrillation threshold throughout a critical mass of myocardium but does not cause further local dysfunction. The distribution of current is altered by the relative positions of the two electrodes. European guidelines for electrode (paddle) placement during defibrillation are based on empirical studies and traditional practice. However, there is increasing evidence to suggest that bi-axillary electrode placement may be superior to traditional antero-apical and antero-posterior positions.

Trauma audit: clinical judgement or statistical analysis?

Comparisons have been made between two methods currently used to assess the effectiveness of management of major trauma. These are the review of fatal cases by senior clinicians and the use of statistical analysis of severity scores. The former was assessed by a re-examination of the Coroners' reports of 508 patients reviewed by senior clinicians at the request of The Royal College of Surgeons of England Working Party on the Management of Patients with Major Injuries. The latter was based on the 665 fatalities on the files of the UK Major Trauma Outcome Study. The two groups of patients had comparable age and sex profiles and broadly similar ranges of injury severity. There were major differences between and inconsistencies within the two assessments. Clinicians more frequently judged death avoidable in those with very severe injuries. In contrast, the statistical analysis suggested, paradoxically, that the proportion of avoidable deaths in those patients who had minor injuries was less than the proportion of avoidable deaths in those who had more serious injuries. These variations underline the limited values of retrospective peer review and will not encourage clinicians to adopt currently available statistical methods. Further refinements of anatomical and physiological scoring systems and their integration to provide a statistically valid and clinically acceptable measure of outcome are essential prerequisites to the wider introduction and success of trauma audit.

The emergency department and the community: a model for improved cooperation.

Improved emergency care may be achieved by closer integration of hospital and community management. This has been promoted in Salford by the appointment of an Emergency Services Practice Manager jointly funded by the Family Health Services Authority and Salford Health Authority. Communication has improved, complementary working relationships developed and health promotion initiatives established.

Alcohol consumption of patients attending two accident and emergency departments in north-west England.

The impact of alcohol use on the workload of two accident & emergency departments in north-west England was assessed by blood alcohol concentration (BAC) measurement, inspection of clinical records and interview of all patients aged 16 and over attending throughout a two-week period. The frequency of intoxication was similar to the previous reported rate in Scotland: 13.2% of all patients had a positive BAC. Inebriated injured patients arrived at all times of the day--varying in frequency from 2.5% of midday attenders to 78% of those presenting after midnight. The incidence of alcohol-related industrial accidents was low, but 60% of all assaulted patients were inebriated, many having sustained head injuries. Of patients attending within 2 hours of an accident at home, 19% also had a positive BAC, but 92% of those with ankle sprains were sober. Patients in lower social classes reported higher rates of alcohol consumption. The popularity of beer in comparison to wines and spirits was inversely related to age and unrelated to social class. Alcohol abuse is commonly associated with injuries sustained at home and with assaults occurring in public places. Prevention campaigns directed at the reduction of these types of incidents should be as concerned with the inebriation of the patient as with the architectural, environmental and legal framework within which the 'accident' occurs.

Measuring the severity of injury.

Attempts have been made to improve the Injury Severity Score (ISS) system of Baker et al. (1974) using plasma lactate data obtained from 277 patients shortly after injury and before treatment. The ISS is based on the Abbreviated Injury Scale (AIS) values of the individual injuries, being the sum of the squares of the values for the three most severely injured regions. Log (plasma lactate concentration) is positively related to ISS over its whole range. It was not possible to vary the AIS values, either on clinical grounds or using a computer, in such a way that the variance of the log (plasma lactate concentration) about its regression line with ISS was significantly reduced. With a score based on the sum of the squares of the AIS values for all the patient's injuries, some improvement to the AIS values could be made but it was not statistically significant. At the present time Baker's ISS method would seem to be the best way of grading injuries for acute studies.

Preliminary analysis of the care of injured patients in 33 British hospitals: first report of the United Kingdom major trauma outcome study.

OBJECTIVE: To measure the effectiveness of management of major trauma in the United Kingdom. DESIGN: Review of the care of all seriously injured patients seen over two years. SETTING: 33 hospitals which receive patients who have sustained major trauma. SUBJECTS: 14,648 injured patients admitted for more than three days, transferred or admitted into an intensive care bed, or dying from their injuries. MAIN OUTCOME MEASURE: Death or survival in hospital within three months of the injury. RESULTS: 21% of seriously injured patients (1299) took longer than one hour to reach hospital. Time before arrival at hospital was not related to severity of injury. A senior house officer was in charge of initial hospital resuscitation in 57% (826/1445) of patients with an injury severity score > or = 16. More senior staff were commonly responsible for definitive operations, but only 46% (165/355) of patients judged to require early operation arrived in theatre within two hours. Mortality for 6111 patients sustaining blunt trauma and treated in the 14 busiest hospitals was significantly higher (actual 408, predicted 295.6, p < 0.001) than in a comparable North American dataset. Large differences in the 14 hospitals assessed could not be explained by variations in case load or facilities. In contrast, the outcome of the 4.1% (597) of patients with penetrating injuries was better than that of a comparable group in the United States. Analysis of the 415 penetrating injuries with complete data showed that 15 patients died (19.3 predicted; p = 0.04). CONCLUSIONS: The initial management of major trauma in the United Kingdom remains unsatisfactory. There are delays in providing experienced staff and timely operations. Mortality varies inexplicably between hospitals and, for blunt trauma, is generally higher than in the United States.

Doctors' legal position in treating temporarily incompetent patients.

Doctors in accident and emergency departments are sometimes presented with patients with potentially life threatening conditions who refuse to consent to treatment. The doctors then face a dilemma: to withhold necessary treatment or to act against a patient's express wishes. Two such cases are presented, and we asked a lawyer, two medical ethicists, a psychiatrist, and an accident and emergency physician to comment on the implications.

Triage: a literature review 1985-1993.

Following an extensive literature review of Accident and Emergency (A & E) nursing from 1985-1993, the authors focused upon triage. A wide range of issues related to triage and its use in A & E departments are examined. An appendix is included to clarify major research finds in this area. Many of the claims made regarding triage require further investigation.

Grief support in accident and emergency nursing: a literature review 1985-1993.

On completing a wide ranging review of literature related to Accident and Emergency (A & E) nursing, the authors chose to focus upon grief support. The literature ranges from personal experiences to large scale research. A table of studies is included to clarify major research findings in this area. The article concludes by recommending long term support for bereaved relatives and research to demonstrate the value of support for relatives in the community.

[CRASH--the first large randomized controlled study of head injuries]. / CRASH--první velká randomizovaná kontrolovaná studie u úrazu hlavy.

CRASH (www.crash.lshtm.ac.uk) is already today the most extensive randomized controlled study of patients with head injuries which was implemented, but its completion and statistical evaluation will be possible only when it achieves the planned and necessary 20,000 enlisted patients. This calls for unselfish cooperation of physicians and nurses world-wide. In the Czech Republic so far six departments participate in the study and we would be glad if this number would increase substantially.