Identifying and comparing risks in emergency medicine

OBJECTIVES

To identify common risk types occurring in emergency departments (EDs). To compare the risks occurring between different emergency departments.

DESIGN

Application of a typology of risks to a database of critical incidents. Comparison of results of applying typology to group of critical incidents collected in a uniform manner in four different EDs.

SETTING

EDs in two teaching hospitals and two district general hospitals in the north west of England.

INTERVENTIONS

Observational study.

MAIN OUTCOME MEASURES

Types of critical incidents identified. Statistical comparisons between EDs.

RESULTS

816 critical incidents were classified. Patient assessment omission failures were the commonest type of failure, accounting for 291 (35.6%) of the critical incidents. Level 1 and level 2 failures accounted for 254 (31.1%) of critical incidents. Significant differences (p = 0.009) were shown between EDs when the categories of critical incidents occurring were compared. No significant differences (p = 0.336) were shown between EDs when the levels of severity of critical incidents occurring were compared.

CONCLUSIONS

Large numbers of critical incidents with potentially fatal consequences occur. The types of risks differ significantly between different EDs.

Co-existent primary cutaneous anaplastic large cell lymphoma and lymphomatoid papulosis

We describe the case of a 37-year-old female with a history of psoriasiform dermatitis who presented with multicentric primary cutaneous CD30-positive anaplastic large T cell lymphoma (ALCL). Despite aggressive systemic therapy, the patient suffered multiple relapses and the lymphoma spread to cervical and inguinal lymph nodes. Later in her clinical course it was appreciated that she was also suffering from lymphomatoid papulosis (LyP). The case illustrates the overlapping clinical, histological and immunophenotypic features of ALCL and LyP, conditions which represent a spectrum of CD30-positive lymphoproliferative disease. A multidisciplinary approach between dermatologist, oncologist and pathologist is essential for the optimal management of these complex conditions.

Quantitative assessment of the radiation hazards and risks in sentinel node procedures

Sentinel node localization using an injected radiopharmaceutical and a gamma probe is performed in many hospitals. Employers have a duty to give appropriate training to staff who may not have been previously formally trained to work with unsealed radioactive sources. A study was performed to assess hazards and risks at all stages of the localization procedure. Whole body doses and finger doses of imaging, surgery and pathology staff were determined. The activity remaining in the tumour specimen, excised nodes and disposable waste from the operating theatre was measured. Any radioactive contamination of the operating theatre and equipment was also ascertained. All results were then assessed in light of current UK radiation protection legislation for the protection of staff and members of the public. Results showed that radiation doses are low and no additional procedures are required for protection of staff, provided the usual procedures for biohazards are in place. However, an information sheet has been prepared for the reassurance of staff, and theatre swabs may need to be stored temporarily before disposal. Injecting and imaging on the day before surgery is preferred, compared with injecting and imaging before surgery on the same day, since this gives lower radiation doses to staff, lower activity in excised specimens and waste, and provides a higher count rate giving better image quality.

Physiological interpretation of electrical impedance epigastrography measurements

Measurement of the electrical impedance of the gastric region is carried out with the epigastrograph. This generates and applies alternating current around the abdominal area and measures the potential difference in order to determine the impedance externally, via electrodes. The change of epigastric impedance for a subject, given a meal after fasting, depends on the conductivity of the meal compared to the stomach and surrounding tissues. Typically a conductive meal has conductivity >7 mS cm(-1), non-conductive <2 mS cm(-1) and neutral about 4.5 mS cm(-1). Half-emptying times (T50s) from gastric emptying studies in volunteers using three test meals of 450 ml volume were obtained and found to be shorter than expected from the literature. The meals were a 10% glucose solution and two milk shakes of energy 1,300 kJ and 2,850 kJ, respectively. These electrical impedance epigastrography (EIE) measurements were carried out with scintigraphy. The T50 values of the latter were significantly longer. The direct comparison of the normalized experimental data obtained by both methods led to the concept that EIE measurements are mainly influenced by gastric secretion. Thus the EIE trace of a 'neutral' meal suggests the hypothesis that the volume of the meal is not the significant factor but is influenced by gastric acid secretions. Physiology of the gastric mucosa during the digestion of a meal and intragastric pH values also suggests this. Gastric function studies using EIE measurements may therefore reflect gastric ionic concentration rather than the volume of the contents of the stomach. In turn this could lead to the development of a non-invasive method for the continuous recording of gastric acid secretions.

Disability in children from different ethnic populations

We report on the prevalence of severe neurodisability in children in the Southern Derbyshire Health Authority from different ethnic groups. Information was obtained from the health records of children at the Child Development Centre (CDC), and analysed according to ethnic group. There were 53 in the Pakistani group, 20 in the Indian group and 764 in a mixed group, of which 95% were of European origin. It was estimated that all children with severe disability in the area of the Health Authority had notes at the CDC, except for 10% of the mixed group living on the periphery. The numbers of children with different disabling conditions were recorded, together with a measure of the level of individual disability; the 'Disability Scores'. We also noted if the condition was genetic or chromosomal in origin. Pakistani children showed a higher prevalence than the other groups of severe learning disorder, severe and profound hearing loss and severe visual problems. They also had a slightly increased prevalence of autism and cerebral palsy. Conversely, they showed a lower prevalence of language disorder. Disability scores for Pakistani children attending the CDC were higher than for other groups. Genetic disease causing disability was 10 times more common in the Pakistani children than other ethnic groups. Disability is more common in Pakistani children probably as a result of the cultural practice of consanguineous marriages. This community needs special help for disabled children, and their families, for general support and appropriate genetic counselling.

Fumigation with carbonyl sulfide: a model for the interaction of concentration, time and temperature

The new fumigant carbonyl sulfide offers an alternative to both methyl bromide and phosphine as a grain fumigant. Separate mathematical models for levels of kill, based on quantitative toxicological studies were developed for adults and eggs of the rice weevil Sitophilus oryzae (L.). These models suggest that fumigation exposure times for carbonyl sulfide will be a compromise between those of methyl bromide (typically 24h) and phosphine (7-10d) to achieve a very high kill of all developmental stages. S. oryzae eggs were more difficult to kill with carbonyl sulfide fumigation than the adults. At 30 degrees C, a 25gm(-3) fumigation killed 99.9% of adults in less than 1d, but took 4d to kill the same percentage of eggs. Models were generated to describe the mortality of adults at 10, 15, 20, 25 and 30 degrees C. From these models it is predicted that fumigation with carbonyl sulfide for 1-2d at 30gm(-3) will kill 99.9% of adults. Furthermore the models illustrate that fumigations with concentrations below 10gm(-3) are unlikely to kill all adult S. oryzae. Significant variation was observed in the response of eggs to the fumigant over the temperature range of 10 to 30 degrees C. Models were generated to describe the mortality of eggs at 10, 15, 20, 25 and 30 degrees C. As the temperature was reduced below 25 degrees C, the time taken to achieve an effective fumigation increased. Extrapolating from the models, a 25gm(-3) fumigation to control 99.9% of S. oryzae eggs will take 95h (4d) at 30 degrees C, 77h (3.2d) at 25 degrees C, 120h (5d) at 20 degrees C, 174h (7.5d) at 15 degrees C and about 290h (11d) at 10 degrees C. The role of temperature in the time taken to kill eggs with carbonyl sulfide cannot be ignored. In order to achieve the desired level of kill of all developmental stages, the fumigation rates need to be set according to the most difficult life stage to kill, in this instance, the egg stage.

Depression accounts for executive function deficits in obsessive-compulsive disorder

OBJECTIVE

To examine the relative impact of depression on executive function deficits in obsessive-compulsive disorder (OCD).

BACKGROUND

Existing data suggest that OCD is associated with basal ganglia and orbital frontal dysfunction, and neurobehavioral abnormalities that are putatively associated with these regions have been demonstrated in OCD. Nonetheless, few studies have accounted for the effects of depression, which is a common concurrent symptom among those with OCD.

METHOD

A broad battery of neuropsychological tests, including measures of executive function and sensory-motor function, was administered to 20 adults with OCD and 31 control subjects. To assess depressive severity, participants were administered the depression scale from the Minnesota Multiphasic Personality Inventory.

RESULTS

Data were analyzed using a regression model in two steps. In step one, patient group was entered, and patients with OCD demonstrated a pattern of executive function and sensory-motor deficits, similar to those shown in previous research. In step two, self-reported depressive symptom severity was entered as a predictor. As a consequence, depression accounted for some executive function deficits, whereas presence of OCD only predicted performance on measures of sensory-motor function.

CONCLUSIONS

These data suggest that abnormalities involving executive function in OCD are related to co-morbid depressive severity. However, sensory-motor deficits seem to be more consistent with basal ganglia/orbital frontal dysfunction in OCD.

Opinion statement on the minimal acceptable standards of healthcare in cerebral palsy

PURPOSE

Recent studies have shown a marked variation in the standards of healthcare for young people with disabilities in different regions of the UK and even within the same health district. Equity in the provision of healthcare is a fundamental principle of the NHS. However, this can only be measured against an agreed minimal standard of healthcare that serves as a benchmark for healthcare purchasers and providers. The aim of the present document is to develop a set of minimum standards of healthcare for children and adults with cerebral palsy (CP).

METHODS

The document was developed in two stages by a multi-professional and multi-disciplinary group of practitioners in the field of CP. Initially, members of the panel jointly formulated a statement of what they believed should be the minimal acceptable standards of healthcare in CP drawing on their own experience and the published scientific evidence. In the second stage the views of some of the relevant professional bodies and voluntary organizations on the draft statement were sought. The responses of these organizations were incorporated into the final document if agreed by the panel.

RESULTS AND CONCLUSIONS

Twenty-two recommendations were made. These were considered the minimum standards of care in a district general hospital. The emphasis was on the organisation and delivery of healthcare for children with CP. The statement is intended to stimulate debate especially in relation to the equity of service provision throughout the country and may be used to inform purchasers of healthcare. Similarly, it may also be useful to providers of healthcare as an audit tool.

A comparison of the development and survival of the dung beetle, Onthophagus taurus (Schreb.) when fed on the faeces of cattle treated with pour-on formulations of eprinomectin or moxidectin

Faeces voided by 1-year old cattle at 3-70 days after treatment with a pour-on formulation of moxidectin had no detectable effects on development or survival of the common dung beetle Onthophagus taurus. In contrast, faeces voided by cattle treated with a pour-on formulation of eprinomectin were associated with high juvenile mortality during the first 1-2 weeks after treatment. Increased mortality also occurred among newly emerged beetles fed on faeces collected 3 days after eprinomectin treatment and there was evidence of suppressed brood production among those that survived. This effect was still apparent even after insects fed for a further 10 days on the faeces of untreated cattle. A model simulating the effects of drug residues on dung beetle populations suggests that in the absence of immigration a single treatment of eprinomectin is capable of reducing beetle activity in the next generation by 25-35%. Effects are likely to be greatest when treatment coincides with emergence of a new generation of beetles.

Statistical analysis of decay of organophosphorus and pyrethroid insecticides and carbaryl on paddy rice, maize, sunflowers and field peas

A model is developed to describe the decay of seven insecticides on stored paddy rice, maize, sunflowers and peas, and is shown to be more precise than each of six literature models on pesticide decay. It relates residues (R), as a ratio of applied concentration (R(0)), to time after insecticide application (t), modifying the usual first-order kinetics equation lnR=lnR(0)-kt by assuming that the rate constant k has a mixture of values according to a gamma distribution with mean K. The resulting equation is lnR=lnR(0)-Kcln(1+t/c), where c is a constant determined empirically. For large c, this model reduces to the first-order model with K=k. The parameter K is further modelled as linear in temperature for maize and rice. The rate of loss of protectants was found not to be seriously affected by co-application with other insecticides, and this is a useful finding for future studies on rates of loss of grain protectants. The apparent rate of loss was also not seriously affected by the method of analysis, whether by gas chromatography or high-performance liquid chromatography, and this finding supports previous validation of the methods.

End-stage renal disease: factors affecting referral decisions by family physicians in Canada, the United States, and Britain

The objective of this study is to determine how patient age, sex, creatinine level, and comorbidity affect referral decisions for the treatment of end-stage renal disease (ESRD) and whether these decisions are affected by physician characteristics in three countries: Canada, the United States, and Britain. A vignette-based questionnaire was mailed to a random sample of family physicians in Ontario, Canada (1,818 physicians); all family physicians in the state of New York (1,814 physicians); and a sample of general practitioners from the south of England (2,228 physicians) in 1996. Physicians were presented with clinical scenarios involving a patient with varying degrees of renal insufficiency and a complicating comorbidity, including angina, diabetes, cancer, mental illness, or socioeconomic circumstances. They were asked to indicate the likelihood of referral. Half the physicians received a questionnaire describing a male patient, and half, a female patient. Mean creatinine levels at which physicians would refer were 260 micromol/L for British physicians, 297 micromol/L for Canadian physicians, and 340 micromol/L for American physicians. No difference in referral rates was found based on the sex of the patient or physician. Sixty-five percent of American and Canadian physicians would refer regardless of patient age, but only 49% of British physicians would do so. Family physicians in the United States, Canada, and Britain function as gatekeepers for patients with ESRD. They are less likely to refer based on increasing severity of comorbid conditions. They also discriminate based on age, but not sex.

Safety profile and efficacy of botulinum toxin A (Dysport) in children with muscle spasticity

Botulinum toxin A (BTX-A) is widely used in the management of muscle spasticity in children. However, at present the dose of BTX-A for a given patient is selected empirically. The aim of this study is to provide dosage guidelines that are based on risk/benefit assessment. This was a multicentre retrospective study of the safety profile and efficacy of BTX-A in children with chronic muscle spasticity. Data in 758 patients who received a total of 1594 treatments were analysed (mean age 7.2 years; 429 males, 329 females). Spastic cerebral palsy (CP) was the most common diagnosis (94% of the study sample). Of all treatments 7% resulted in adverse events; incidence was related to the total dose rather than the dose calculated on the basis of body weight. The highest incidence of adverse events was observed in patients who received >1000 IU of BTX-A per treatment session. The odds of an adverse event was 5.1 times greater for this group of patients than for those who had 250 IU or less (p<0.001). A good overall response to treatment was reported in 82% and treatment goals were fully or partially achieved in 3% and 94% of participants respectively. More patients in the highest dose group reported functional deterioration. Interestingly, multilevel treatments resulted in a better response than single-level treatments (odds ratio 1.7, 95% CI 1.3 to 2.2,p=0.001).

Effective partnerships in action: radical options or more of the same?

September 2000 saw the publication in the UK of the first National Health Service (NHS) plan for cancer services. The NHS Cancer Plan (Department of Health (DoH), 2000a) may be one of the most fundamental reforms of national cancer care services ever attempted – just as important is the fact that there is much in it for palliative care. It states:

‘All patients should have access to the specialist palliative care advice and services they need. For most patients, these will be provided in their homes, in the community or in hospital. Some will require the specialist facilities of a hospice. Voluntary palliative care services need to be enabled to play their full role in the cancer network, with adequate funding from the NHS’.

(DoH, 2000a)

Monitoring Crocodylus porosus populations in the Northern Territory of Australia: a retrospective power analysis

In the Northern Territory of Australia, populations of the estuarine crocodile (Crocodylus porosus) have been subject to an annual egg harvest since the early 1980s. Since 1997, adult and juvenile crocodiles have also been harvested in some catchments. Annual surveys of crocodile populations are conducted in order to ensure that the harvest is sustainable. Boat surveys commenced in 1975 and helicopter surveys commenced in 1989. Retrospective power analysis was used to determine whether the sampling program meets the objectives of the Crocodile Management Program for the Northern Territory. Data collected during boat surveys vary in quality between river systems. The analysis of pooled data from 7 river systems with a residual standard deviation of 0.11 indicates that the power of the current spotlight survey method to detect a decline of 10% per annum in around 4 years is about 0.9. In this time the population would decline by around 33% and would fully recover in 8 years following the removal of the factor causing the decline. This allows detection of a decline within one-third, and recovery within two-thirds, of the estimated generation time of the saltwater crocodile and will allow management actions to be implemented before the impacts on populations are serious. The data from helicopter and boat surveys from a 10-year period were compared. Helicopter surveys did not provide useful management information.

Special study modules in medical illustration in the undergraduate medical curriculum

The General Medical Council's recommendations on undergraduate medical education, published in December 1993 under the title of 'Tomorrow's Doctors', put forward the concept of the Special Study Module (SSM) as part of the medical undergraduate curriculum. This was to have a major impact on medical schools, requiring them to introduce a new element into their teaching and calling for input from departments not normally involved in the delivery of the undergraduate course. The Media Resources Centre in the University of Wales College of Medicine saw the introduction of SSMs as an opportunity to contribute to the education of medical students in ways that had not been possible previously. Several SSMs are now offered by the Centre and involvement in the SSM programme has been an interesting and rewarding experience.

Epstein Barr virus genome in nasopharyngeal carcinomas from New Zealand

BACKGROUND

The population in New Zealand is a heterogeneous mix of Caucasians (80%), Maori (9%), and Polynesians (10%). It is believed that the Polynesians are of Chinese descent and may harbor the same high incidence of nasopharyngeal carcinoma (NPC). In addition, it is not known whether the Epstein-Barr virus (EBV) is as closely associated with the development of NPC in Polynesians as it is in those of Chinese origin.

METHODS

This study reexamines the associative correlation between EBV and NPC with two methods of genetic detection, polymerase chain reaction (PCR) and in-situ hybridization (ISH). In addition, geographic heterogeneity was analyzed to determine whether there are differences in the prevalence of EBV in NPCs among the ethnic mixed populations found in New Zealand. Nasopharyngeal biopsy specimens from 20 patients with NPC and 36 controls were obtained from Auckland.

RESULTS

With PCR, EBNA-1, a genomic sequence of EBV in NPC samples was able to be detected with 76.5% sensitivity and 96.7% specificity. By use of ISH, EBV was detected in NPC tissue with 82.4% sensitivity and 100% specificity.

CONCLUSION

There seems to be no geoanthropologic differences in terms of the association of EBV with NPC.

The changing role of the medical illustrator

The annual meeting of the Australian Institute of Medical and Biological Illustration in Melbourne in November 1998 included keynote addresses from Richard Morton and Robin Williams. Both speakers looked at the future of the medical illustration profession, and in particular the impact of new technology. This matter was also addressed by Joe Nicholls in a presentation given at the Institute of Medical Illustrators' Annual Symposium in Warwick, UK, in September 1998. This paper is a synthesis of the ideas presented by these three speakers and elaborates on common themes in their presentations.

Chest pain with nondiagnostic electrocardiogram in the emergency department: a randomized controlled trial of two cardiac marker regimens

BACKGROUND

Early detection of acute myocardial infarction (AMI) may save lives. In the emergency setting, it is unclear whether the early use of certain cardiac markers (myoglobin and cardiac troponin I [cTnI]) assists in making appropriate decisions whether to admit or discharge patients with chest pain of possible ischemic cause who have nondiagnostic electrocardiograms (ECGs). We performed a study to determine whether the addition of new cardiac markers in the emergency department results in improved clinical decisions.

METHODS

A single-blind randomized controlled trial was conducted between June 1997 and June 1998 in a tertiary care emergency department in Kingston, Ont. Of 296 patients aged 30 years or more who presented to the emergency department with chest pain and nondiagnostic ECGs, 146 were randomly assigned to the intervention group (determination of baseline creatine kinase [CK] level, CK MB fraction and cTnI level, and myoglobin level at baseline and at 2 hours) and 150 to the control group (determination of baseline CK level and CK MB fraction). Outcome measures included the rate of admission to the inpatient cardiology service and length of stay in the emergency department.

RESULTS

Of the 296 patients, 34 (11.5%) received a diagnosis of AMI in the emergency department, and 92 (31.1%) had chest pain of noncardiac cause. Patients in the intervention group were less likely than those in the control group to be admitted to the cardiology service (67 [45.9%] v. 81 [54.0%]). The absolute difference in the proportion (8.1% [95% confidence interval -3.3 to 19.5]), although potentially important clinically, was not statistically significant. The length of stay in the emergency department was essentially the same in the 2 study groups. At 30 days, the proportions of patients with a diagnosis of recurrent angina (58.2% in the intervention group and 58.0% in the control group) and AMI (12.3% and 14.7%) were also similar.

INTERPRETATION

The optimal cardiac marker panel to be used in the emergency department remains unknown. The addition of serial testing of myoglobin with cTnI confirmation to the standard panel did not substantially change the clinical management or outcomes of patients presenting with chest pain and nondiagnostic ECGs.