Open tibial fractures in major trauma centres: A national prospective cohort study of current practice

AIMS

To assess current national practice in the management of severe open tibial fractures against national standards, using data collected by the Trauma and Audit Research Network.

MATERIALS AND METHODS

Demographic, injury-specific, and outcome data were obtained for all grade IIIB/C fractures admitted to Major Trauma Centres in England from October 2014 to January 2016.

RESULTS

Data was available for 646 patients with recorded grade IIIB/C fractures. The male to female ratio was 2.3:1, mean age 47 years. 77% received antibiotics within 3 h of admission, 82% were debrided within 24 h. Soft tissue coverage was achieved within 72 h of admission in 71%. The amputation rate was 8.7%. 4.3% of patients required further theatre visits for infection during the index admission. The timing of antibiotics and surgery could not be correlated with returns to theatre for early infection. There were significant differences in the management and outcomes of patients aged 65 and over, with an increase in mortality and amputation rates.

CONCLUSIONS

Good outcomes are reported from the management of IIIB/C fractures in Major Trauma Centres in England. Overall compliance with national standards is particularly poor in the elderly. Compliance did not appear to affect rates of returning to theatre or early infection. Appropriately applied patient reported outcome measures are needed to enhance the evidence-base for management of these injuries.

The impact of age on major orthopaedic trauma: an analysis of the United Kingdom Trauma Audit Research Network database

AIMS

To compare the early management and mortality of older patients sustaining major orthopaedic trauma with that of a younger population with similar injuries.

PATIENTS AND METHODS

The Trauma Audit Research Network database was reviewed to identify eligible patients admitted between April 2012 and June 2015. Distribution and severity of injury, interventions, comorbidity, critical care episodes and mortality were recorded. The population was divided into young (64 years or younger) and older (65 years and older) patients.

RESULTS

Of 142 765 adults sustaining major trauma, 72 942 (51.09 %) had long bone or pelvic fractures and 45.81% of these were > 65 years old. Road traffic collision was the most common mechanism in the young (40.4%) and, in older people, fall from standing height (80.4%) predominated. The 30 day mortality in older patients with fractures is greater (6.8% versus 2.5%), although critical care episodes are more common in the young (18.2% versus 9.7%). Older people are less likely to be admitted to critical care beds and are often managed in isolation by surgeons. Orthopaedic surgery is the most common admitting and operating specialty and, in older people, fracture surgery accounted for 82.1% of procedures.

CONCLUSION

Orthopaedic trauma in older people is associated with mortality that is significantly greater than for similar fractures in the young. As with the hip fracture population, major trauma in the elderly is a growing concern which highlights the need for a review of admission pathways and shared orthogeriatric care models. Cite this article: Bone Joint J 2017;99-B:1677-80.

Regionalisation of trauma care in England

AIMS

We aimed to determine whether there is evidence of improved patient outcomes in Major Trauma Centres following the regionalisation of trauma care in England.

PATIENTS AND METHODS

An observational study was undertaken using the Trauma Audit and Research Network (TARN), Hospital Episode Statistics (HES) and national death registrations. The outcome measures were indicators of the quality of trauma care, such as treatment by a senior doctor and clinical outcomes, such as mortality in hospital.

RESULTS AND CONCLUSION

A total of 20 181 major trauma cases were reported to TARN during the study period, which was 270 days before and after each hospital became a Major Trauma Centre. Following regionalisation of trauma services, all indicators of the quality of care improved, fewer patients required secondary transfer between hospitals and a greater proportion were discharged with a Glasgow Outcome Score of "good recovery". In this early post-implementation analysis, there were a number of apparent process improvements (e.g. time to CT) but no differences in either crude or adjusted mortality. The overall number of deaths following trauma in England did not change following the national reconfiguration of trauma services. Evidence from other countries that have regionalised trauma services suggests that further benefits may become apparent after a period of maturing of the trauma system. Cite this article: Bone Joint J 2016;98-B:1253-61.

Traumatic brain injury in England and Wales: prospective audit of epidemiology, complications and standardised mortality

OBJECTIVES

To provide a comprehensive assessment of the management of traumatic brain injury (TBI) relating to epidemiology, complications and standardised mortality across specialist units.

DESIGN

The Trauma Audit and Research Network collects data prospectively on patients suffering trauma across England and Wales. We analysed all data collected on patients with TBI between April 2014 and June 2015.

SETTING

Data were collected on patients presenting to emergency departments across 187 hospitals including 26 with specialist neurosurgical services, incorporating factors previously identified in the Ps14 multivariate logistic regression (Ps14ⁿ) model multivariate TBI outcome prediction model. The frequency and timing of secondary transfer to neurosurgical centres was assessed.

RESULTS

We identified 15 820 patients with TBI presenting to neurosurgical centres directly (6258), transferred from a district hospital to a neurosurgical centre (3682) and remaining in a district general hospital (5880). The commonest mechanisms of injury were falls in the elderly and road traffic collisions in the young, which were more likely to present in coma. In severe TBI (Glasgow Coma Score (GCS) ≤8), the median time from admission to imaging with CT scan is 0.5 hours. Median time to craniotomy from admission is 2.6 hours and median time to intracranial pressure monitoring is 3 hours. The most frequently documented complication of severe TBI is bronchopneumonia in 5% of patients. Risk-adjusted W scores derived from the Ps14ⁿ model indicate that no neurosurgical unit fell outside the 3 SD limits on a funnel plot.

CONCLUSIONS

We provide the first comprehensive report of the management of TBI in England and Wales, including data from all neurosurgical units. These data provide transparency and suggests equity of access to high-quality TBI management provided in England and Wales.

Mortality from trauma haemorrhage and opportunities for improvement in transfusion practice

Background

The aim of this study was to describe the prevalence, patterns of blood use and outcomes of major haemorrhage in trauma.

Methods

This was a prospective observational study from 22 hospitals in the UK, including both major trauma centres and smaller trauma units. Eligible patients received at least 4 units of packed red blood cells (PRBCs) in the first 24 h of admission with activation of the massive haemorrhage protocol. Case notes, transfusion charts, blood bank records and copies of prescription/theatre charts were accessed and reviewed centrally. Study outcomes were: use of blood components, critical care during hospital stay, and mortality at 24 h, 30 days and 1 year. Data were used to estimate the national trauma haemorrhage incidence.

Results

A total of 442 patients were identified during a median enrolment interval of 20 (range 7–24) months. Based on this, the national incidence of trauma haemorrhage was estimated to be 83 per million. The median age of patients in the study cohort was 38 years and 73·8 per cent were men. The incidence of major haemorrhage increased markedly in patients aged over 65 years. Thirty-six deaths within 24 h of admission occurred within the first 3 h. At 24 h, 79 patients (17·9 per cent) had died, but mortality continued to rise even after discharge. Patients who received a cumulative ratio of fresh frozen plasma to PRBCs of at least 1 : 2 had lower rates of death than those who received a lower ratio. There were delays in administration of blood. Platelets and cryoprecipitate were either not given, or transfused well after initial resuscitation.

Conclusion

There is a high burden of trauma haemorrhage that affects all age groups. Research is required to understand the reasons for death after the first 24 h and barriers to timely transfusion support.

Factors affecting conditional discrimination learning by pigeons

In Experiment 1 (within subjects) and Experiment 2 (between subjects) it was shown that the sequential training of pigeons on a color discrimination and then on its reversal, each in a different floor-tilt/texture context, failed to produce conditional control of discriminative performance by those contexts. Daily alternation between the two problems (with correlated contexts) was successful, however. In each of these experiments conditional control was better reflected in generalization test performance in extinction than during sessions of training with reinforcement.

A major trauma centre is a specialty hospital not a hospital of specialties

BACKGROUND

High estimates of preventable death rates have renewed the impetus for national regionalization of trauma care. Institution of a specialist multidisciplinary trauma service and performance improvement programme was hypothesized to have resulted in improved outcomes for severely injured patients.

METHODS

This was a comparative analysis of data from the Royal London Hospital (RLH) trauma registry and Trauma Audit and Research Network (England and Wales), 2000-2005. Preventable mortality was evaluated by prospective analysis of the RLH performance improvement programme.

RESULTS

Mortality from critical injury at the RLH was 48 per cent lower in 2005 than 2000 (17.9 versus 34.2 per cent; P = 0.001). Overall mortality rates were unchanged for acute hospitals (4.3 versus 4.4 per cent) and other multispecialty hospitals (8.7 versus 7.3 per cent). Secondary transfer mortality in critically injured patients was 53 per cent lower in the regional network than the national average (5.2 versus 11.0 per cent; P = 0.001). Preventable death rates fell from 9 to 2 per cent (P = 0.040) and significant gains were made in critical care and ward bed utilization.

CONCLUSION

Institution of a specialist trauma service and performance improvement programme was associated with significant improvements in outcomes that exceeded national variations.

Paediatric trauma: injury pattern and mortality in the UK

OBJECTIVE

Trauma accounts for a large proportion of childhood deaths. No data exist about injury patterns within paediatric trauma in the UK. Identification of specific high-risk injury patterns may lead to improved care and outcome.

METHODS

Data from 24 218 paediatric trauma cases recorded by the Trauma Audit and Research Network (TARN) from 1990 to 2005 were analysed. Main injury, injury patterns and outcome were analysed. Mortality at 93 days' post-injury was the major outcome measure.

RESULTS

Limb injuries occurred in 65.0% of patients. In infants 81.4% of head injuries were isolated, compared with 46.5% in 11-15-year-old children. Thoracic injuries were associated with other injuries in 68.4%. The overall mortality rate was 3.7% (n = 893). Mortality decreased from 4.2% to 3.1%; this was most evident in non-isolated head injuries. It was low in isolated injuries: 1.5% (n = 293). In children aged 1-15 years the highest mortalities occurred in multiple injuries including head/thoracic (47.7%) and head/abdominal injuries (49.9%). Having a Glasgow Coma Scale of <15 on presentation to hospital was associated with a mortality of 16%.

CONCLUSIONS

Differences in injury patterns and mortality exist between different age groups and high-risk injury patterns can be identified. With increasing age, a decline in the proportion of children with head injury and an increase in the proportion with limb injury were observed. This information is useful for directing ongoing care of severely injured children. Future analyses of the TARN database may help to evaluate the management of high-risk children and to identify the most effective care.

The effect of working hours on outcome from major trauma

OBJECTIVE

To determine whether being admitted with major trauma to an emergency department outside rather than within working hours results in an adverse outcome.

METHODS

The data were collected from hospitals in England and Wales participating in the Trauma Audit and Research Network (TARN). Data from the TARN database were used. Admission time and discharge status were cross matched, and this was repeated while controlling for Injury Severity Score (ISS) values. Logistic regression was carried out, calculating the effects of Revised Trauma Score (RTS), ISS, age, and time of admission on outcome from major trauma. This allowed observed versus expected mortality rates (Ws) scores to be compared within and outside working hours. As much of the RTS data were missing, this was repeated using the Glasgow Coma Score instead of RTS.

RESULTS

In total, 5.2% of people admitted "out of hours" died, compared with 5.3% of people within working hours, and 12.2% of people admitted outside working hours had an ISS score greater than 15, compared with 10.1% admitted within working hours. Outcome in cases with comparable ISS values were very similar (31.1% of cases with ISS >15 died out of hours, compared with 33.5% inside working hours.) The subgroup of data with missing RTS values had a significantly increased risk of death. Therefore, GCS was used to calculate severity adjusted odds of death instead of RTS. However, with either model, Ws scores were identical (both 0%) within and outside working hours.

CONCLUSIONS

Out of hours admission does not in itself have an adverse effect on outcome from major trauma.

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.

Lack of change in trauma care in England and Wales since 1994

To demonstrate trends in trauma care in England and Wales from 1989 to 2000.

STUDY POPULATION

Database of the Trauma Audit and Research Network that includes hospital patients admitted for three days or more, those who died, were transferred or admitted to an intensive care or high dependency area.

METHOD

To demonstrate trends in outcome, severity adjusted odds of death per year of admission to hospital were calculated for all hospitals (n=99) and 20 hospitals who had participated since 1989 (adjustments are for Injury Severity Score, age, and Revised Trauma Score). The grade of doctor initially seeing the injured patient in accident and emergency and median prehospital times per year of admission were calculated to demonstrate trends in the process of care. Trend analyses were carried out using simple linear regression (odds ratio versus year).

RESULTS

The analysis shows a significant reduction in the severity adjusted odds of death of 3% per year over the 1989-2000 time period (p=0.001). During the period 1989-1994 the odds of death declined most steeply (on average 6% per year p=0.004). Between 1994 to 2000 no significant change occurred (p=0.35). This pattern was mirrored by the 20 permanent members where the odds of death also declined more steeply over the 1989-1994 period. The percentage of severely injured patients (ISS >15) seen by a consultant increased from 29 to 40 from 1989-1994 but has remained static subsequently. Median prehospital times for severely injured patients have not changed significantly since 1994 (51 to 45 minutes).

CONCLUSION

Most of the case fatality reduction for trauma patients reaching hospital over the 1989-2000 time period occurred before 1995 when there was most marked change in the initial care of severely injured patients.

Trends in trauma care in England and Wales 1989-97. UK Trauma Audit and Research Network

BACKGROUND

In 1988, the Royal College of Surgeons reported major deficiencies in trauma care in UK hospitals. We investigated whether and how that care has changed in the last decade by use of data collected by the UK Trauma Audit and Research Network.

METHODS

We analysed injury-severity, process, and outcome variables from 91602 patients' records on the database at the end of 1997, collected from 97 (49% of trauma-receiving) hospitals in England, Wales, and two in Ireland. We did longitudinal analyses of odds of death, process variables, and individual hospitals' performance. We took account of potential selection bias from missing data and recruitment of new hospitals.

FINDINGS

The severity-adjusted odds of death after trauma declined gradually from 1989 (odds ratio 1997/1989 0.63 [95% CI [0.49-0.82]). In 1997, the reduction in odds of death was significant even after adjustment for missing data (ratio 1997/1989 0.72 [0.55-0.92]) and recruitment of new hospitals (0.64 [0.44-0.93]). There was significant variability in the proportion of survivors (adjusted for severity of injury and age) between the highest and lowest 10% of UK hospitals. The time between the call to the emergency services and arrival at hospital increased from 32 min in 1989 to 45 min in 1997, irrespective of injury severity. The proportion of severely injured patients seen first by senior doctors increased from 32% to 60%.

INTERPRETATION

Hospital care has made a valuable but variable contribution to reductions in case fatality after injury in the UK in the past 10 years, though further improvement is possible.

Unexpected contribution of moderate traumatic brain injury to death after major trauma

BACKGROUND

The cardiovascular reflex responses to injury and simple hemorrhage are coordinated in the central nervous system. Coincidental brain injury, which is present in 64% of trauma patients who die, could impair these homeostatic responses. The occurrence of hemorrhagic shock in the patient with head injury is also known to increase mortality. Therefore, there is a potential bidirectional interaction between traumatic brain injury and peripheral injury, which would result in an increased mortality when these two injuries coexist. Our objective was to test the hypothesis that moderate traumatic brain injury is an independent predictor of outcome in patients with multisystem trauma.

METHODS

We carried out an analysis of the UK Trauma Audit and Research Network Database. Moderate traumatic brain injury was defined as an Abbreviated Injury Scale score of 3. The study population included 2,717 patients with multisystem injury: 378 patients had a moderate brain injury with peripheral injury, and 2,339 patients had extracranial injury alone. Mortality rates for both groups were compared at increasing injury severity.

RESULTS

Moderate brain injury alone was associated with a mortality rate of 4.2%. However, when combined with extracranial injury, the risk of death was double that attributable to extracranial injury alone (odds ratio, 2.08; 95% confidence interval, 1.57-2.77).

CONCLUSION

This study confirms that the coexistence of moderate traumatic brain injury with extracranial injury is associated with a doubling of the predicted mortality rate throughout the injury severity ranges studied.

Clostridium difficile-associated diarrhea in acute and long-term care facilities

This report presents an overview of the epidemiology, diagnosis, complications, and treatment of Clostridium difficile-associated diarrhea in acute and long-term care facilities. More studies are needed to understand the epidemiology of this disease in long-term care facilities, to identify the risk factors for its recurrence, and to evaluate new treatment modalities.

Trauma care in China: challenge and development

The People's Republic of China has significantly improved the general health of its people by a concerted effort in primary health care but trauma care and its prevention remains a problem. This paper provides an overview of the strengths and weaknesses of the trauma-care system in China and proposes a strategy for its future development. This includes public-health legislation, the integration of military and civilian practice to provide comprehensive care from the scene of the incident through to rehabilitation, medical audit, the introduction of postgraduate trauma-management training courses and international academic exchanges.

Standardized comparison of performance indicators in trauma: a new approach to case-mix variation

An institution's trauma survival rate can be compared with that predicted by TRISS using definitive outcome-based evaluation. This examines W, the difference between actual and predicted survival rates; Z, the statistical significance of this difference; and M, a measure of the similarity of injury severity mix to the prediction data base. However, it is possible for two institutions with the same survival rate within each band of injury severity to have very different W and Z scores whilst retaining a similar M score. Clearly this is unsatisfactory. A new statistic, Ws, is therefore proposed, which is standardized with respect to injury severity mix, producing more accurate comparisons between different institutions. Confidence intervals are used to graphically illustrate the magnitude of Ws, its direction, accuracy, and statistical significance. Data from the U.K. Major Trauma Outcome Study are used to demonstrate the calculations and presentation of Ws and its advantages.

Trauma audit--closing the loop

The philosophy of medical audit and methods of data collection and statistical analysis have been extensively reviewed but less has been written about the effect of audit on medical practice. The measurement of performance is only valuable if it identifies areas of concern and stimulates appropriate change. This paper describes the work of the Salford Trauma Audit Group which has been developed at Hope Hospital, the problems that have been recognized, the strategies that have been introduced to effect change and their influence on management and outcome. Analysis of performance reveals an initial fall in adjusted mortality rate from severe injury after the introduction of resuscitation teams, the adherence to Advanced Trauma Life Support protocols and an integrated multidisciplinary approach to trauma care. Problems remain and there is continuing concern about trauma management in the hospital. This has been reinforced by performance feedback through the Trauma Audit Group which has attracted the interest of senior clinicians in several specialties.

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.

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.

An investigation of the role of possible neural mechanisms in cholera toxin-induced secretion in rabbit ileal mucosa in vitro

1. Cholera toxin stimulates intestinal secretion in vitro by activation of mucosal adenylate cyclase. However, it has been proposed that cholera toxin promotes secretion in vivo mainly through an indirect mechanism involving enteric neural reflexes. 2. We examined this hypothesis further by studying the influence of neuronal blockade on cholera toxin-induced changes in fluid transport across rabbit ileum in vitro. Mucosa, stripped of muscle layers, was mounted in flux chambers and luminal application of crude cholera toxin (2 micrograms/ml) caused a delayed but sustained rise in the short-circuit current, electrical potential difference and Cl- secretion. Pretreatment with the nerve-blocking drug, tetrodotoxin (5 x 10(-6) mol/l serosal side), failed to influence the secretory response to cholera toxin, and addition of tetrodotoxin at the peak response to cholera toxin also had no effect. 3. That tetrodotoxin could block neurally mediated secretagogues was confirmed by the demonstration that the electrical responses to neurotensin (10(-7) mol/l and 10(-8) mol/l) were blocked by tetrodotoxin (5 x 10(-6) mol/l). Furthermore, the response to cholera toxin of segments of ileum, which included the myenteric, submucosal and mucosal nerve plexuses, was not inhibited by tetrodotoxin. 4. We conclude that cholera toxin-induced secretion in rabbit ileum in vitro is not mediated via a neurological mechanism.

Preventability of death from penetrating injury in England and Wales

A total of 1000 deaths from injury in England and Wales have been reviewed to establish the incidence and pattern of penetrating injury and the adequacy of its management. Of the 1000 deaths, 71 (7.1 per cent) were due to penetrating injury. There were 32 knife wounds and 30 firearm injuries. Most of the latter were suicides. Only 17 patients (24 per cent) reached hospital alive. Of these cases, 10 had extracranial injury and all 10 deaths were considered to have been potentially preventable when reviewed by four external assessors. One of seven patients with cranial injury was considered to have been a potentially preventable death. The median age of the 11 cases of potentially preventable death was 37 years (range: 7-61 years). Of these, three did not have any surgery for surgically treatable injuries. Seven patients underwent operation and difficulty was encountered in six of these. It appears from our figures that whilst penetrating injury is an uncommon cause of death, it is poorly managed. The implications of this finding for systems of injury care in the United Kingdom are discussed.

Retrospective study of 1000 deaths from injury in England and Wales

One thousand consecutive deaths from injury in 11 coroner's districts in England and Wales were reviewed by four independent assessors, who studied necropsy reports to identify deaths in hospital that might have been preventable. Of 514 patients admitted to hospital alive, 102 deaths (20%) were judged by all four assessors to have been potentially preventable. When those cases in which three out of four assessors considered that the death was preventable were added the total rose to 170 (33%). Nearly two thirds of all non-central nervous system deaths were judged to have been preventable. The median age of the 170 patients whose deaths were preventable was 41, and the mean Injury Severity Score was 29. Further analysis suggested that the preventable deaths were principally the result of failure to stop bleeding and prevent hypoxia and the absence of, or delay in, surgical treatment. The results closely parallel those from similar studies from the United States and suggest that there are serious deficiencies in the services for managing severe injury in England and Wales. Debate is needed now on how to correct these deficiencies. In particular, the place of trauma centres must be considered.

Inhibition of the effect of serotonin on rat ileal transport by cisapride: evidence in favour of the involvement of 5-HT2 receptors

Cisapride is a synthetic drug which binds, in vitro, to type 2 serotonin receptors. We examined the influence of serotonin and cisapride on ion transport across intestinal mucosa in vitro and studied the effect of cisapride on the response to serotonin. Segments of ileum of male Sprague-Dawley rats were stripped of muscle layers and mounted in flux chambers. The addition of serotonin (10(-8) to 10(-4) M) to the serosal aspect of the mucosa caused a rapid, dose-dependent rise in short circuit current and transmural potential difference. Cisapride alone (5 X 10(-5) M), when added to the mucosal and serosal surfaces, had no effect on the short circuit current, transmural potential difference, resistance, or sodium and chloride fluxes across the mucosa. It did, however, inhibit the response of the mucosa to serotonin (10(-5) M) in a dose dependent manner and blocked it completely at a concentration of 5 X 10(-5) M. Serotonin (5 X 10(-5) M) increased serosal to mucosal flux of chloride from 12.6 +/- 0.8 to 15.2 +/- 0.6 mumol/cm2/h (p less than 0.025), thus reducing net chloride absorption from 4.65 +/- 0.81 to 1.49 +/- 1.04 mumol/cm2/h (p less than 0.05). This effect was completely blocked by cisapride (5 X 10(-5) M). In summary, cisapride inhibits the effect of serotonin on rat ileal ion transport, probably by blocking type 2 serotonin receptors.

In-line measurement of pulmonary metabolic function in the anesthetized rabbit

Quantitative assessment of lung metabolic function is thought to provide biochemical information reflecting integrity of the pulmonary microcirculation. Although multiple indicator-dilution techniques are useful in such pharmacokinetic studies, the need for fractionation and subsequent processing of blood samples greatly prolongs data generation. Accordingly, we designed and tested an in-line system which rapidly can quantify single-pass disposition of photon-emitting substances in the pulmonary circulation of intact animals. The nuclear detection system consisted of a phoswich scintillation probe optically coupled to a photomultiplier tube. Pulses were discriminated for height and shape and counts recorded in a counter-timer, the output of which was interfaced with a personal computer. A mixture of an intravascular reference substance (99mTc-sulfur colloid) and an inhibitor of angiotensin-converting enzyme, N-[1(S)-carboxy-(4-OH-3-[125I]-phenyl) ethyl]-L-alanyl-L-proline (125I-CPAP), was injected as a bolus in the right heart of anesthetized ventilated rabbits and arterial blood was diverted through a flow-cell cuvette directly apposed to the phoswich detector. Single-pass extraction of 125I-CPAP was 39 +/- 3% (mean +/- SE; n = 20) and was depressed in a dose-dependent fashion by the addition of unlabeled CPAP (1-10 micrograms/kg) to the injection. These data indicate that we can now quantify, in the intact animal, saturable binding of an inhibitor to angiotensin-converting enzyme expressed on the surface of the pulmonary microvascular endothelium. Furthermore, such data can be obtained rapidly.

The effect of intermittent compression of the calf on the fibrinolytic responses in the blood during a surgical operation

The fibrinolytic responses in the blood during surgical operation have been studied in two groups of patients during intraoperative intermittent compression of the calf. Fibrinolytic activity did not differ significantly between the groups. The postoperative fibrinolytic shutdown was not prevented by intermittent compression of the calf. It is concluded that, whatever the mechanism by which venous thrombosis is prevented by intermittent compression of the calf, it is not by further stimulation of systemic fibrinolysis.

Alteration in fibrinolytic capacity after operation

The fibrinolytic response to 20 min of forearm venous occlusion was studied in patients undergoing major and minor operations. Fibrinolytic capacity, which is defined as the increase in fibrinolytic activity resulting from a period of venous occlusion, was significantly reduced on the first postoperative day after major operations, but not after minor operations. Since venous occlusion results in the release of plasminogen activator from the vascular endothelium into the blood, these findings suggest that the reduction in the level of spontaneous fibrinolytic activity after major operations is the result either of exhaustion of the vascular endothelium of plasminogen activator or defective synthesis and release of this enzyme from the endothelium.

Plasma fibrinolytic inhibitors after operation

The response of the fibrinolytic system to the stress of a surgical operation has been studied in a group of 39 patients. Fibrinolytic activity was stimulated during the operation but depressed during the early postoperative period. This was accompanied by an increase in the level of fibrinolytic inhibitors in the plasma after operation. This increase in fibrinolytic inhibitors was a result of a significant rise in alpha1 antitrypsin; the level of alpha2 macroglobulin fell both during and after the operation.