Parecoxib and paracetamol for pain relief following minor day-stay gynaecological surgery.

Paracetamol and non-steroidal anti-inflammatory drugs are often administered for postoperative analgesia. Dilatation and curettage, with or without hysteroscopy, is a common day-stay procedure that is associated with pain that is partly mediated by prostaglandins. This study aimed to investigate the analgesic efficacy of adjunctive paracetamol and parecoxib in this setting. A randomised, blinded, placebo-controlled, single-centre trial was conducted among 240 women undergoing dilatation and curettage. Patients were randomised intraoperatively into one of four groups, to receive either intravenous paracetamol 2 g, intravenous parecoxib 40 mg, both in combination, or placebos, post-induction and with intravenous fentanyl. The primary endpoints were pain score one hour postoperatively and the Overall Benefit of Analgesia Score. There were no statistically significant differences in primary outcomes across groups. The area under the curve for pain scores to two hours postoperatively was significantly lower in the group receiving paracetamol (P=0.018) and the need for rescue analgesia with tramadol was less in the combination group (P=0.02). There were no significant differences in patient satisfaction or recovery. We conclude that paracetamol or parecoxib does not produce a clinically important reduction in pain in this setting. Women having uterine curettage and receiving intravenous fentanyl do not appear to benefit from administration of these non-opioid analgesics.

Hyperfibrinolysis diagnosed by rotational thromboelastometry in a case of suspected amniotic fluid embolism.

Rotational thromboelastometry is a viscoelastomeric, point-of-care method for testing haemostasis in whole blood which can be visualised rapidly, in real time, in the operating theatre. Advantages over traditional coagulation tests relate to the rapid feedback of results and the ability to visualise hyperfibrinolysis. We present a case of suspected amniotic fluid embolism that presented with sudden respiratory arrest associated with haemodynamic compromise during a non-elective caesarean delivery. Soon after the collapse, coagulopathy developed. Rotational thromboelastometry showed hyperfibrinolysis and hypofibrinogenaemia, which allowed targeted coagulation factor replacement therapy and the use of tranexamic acid. Hyperfibrinolysis may be a contributor to the coagulopathy associated with amniotic fluid embolism but has been infrequently reported, perhaps due to limited diagnosis with traditional coagulation tests. Treatment of the coagulopathy associated with a suspected amniotic fluid embolism with antifibrinolytic agents may deserve greater consideration.

New formulations of fentanyl for acute pain management.

Intravenous fentanyl citrate has stood the test of time as a valuable formulation for pain management. The desirable physicochemical properties of fentanyl have allowed the development of several alternative formulations for delivery using less invasive routes, for example, transmucosal (intranasal, oral buccal and oral sublingual) and transdermal. These new formulations have been applied to clinical settings in which rapid onset of analgesia is desired, using convenient but noninvasive methods. Recent commercialization of various formulations has been driven largely by the needs of cancer patients, for whom severe but self-limiting "breakthrough" pain is less suitably treated by parenteral or oral routes of opioid administration. However, these formulations are also used for acute analgesia in prehospital and in-hospital emergency department care, and for pediatric acute pain management. Finally, they are increasingly used by patients with chronic pain of nonmalignant origin, although there is considerable debate about their merit in this group. We searched the databases MEDLINE, PubMed, EMBASE, CINAHL and Cochrane up to October 2011, using search terms "fentanyl AND nasal; intranasal; transmucosal; buccal; sublingual; oral; inhaled; inhalation; transdermal". The characteristics of several formulations of fentanyl are reviewed, detailing their pharmacokinetics, pharmacodynamics and clinical experience with their use for acute pain management.

Tramadol in pregnancy and lactation.

Tramadol produces analgesic effects through both non-opioid and weak opioid activity and is commonly used to treat mild to moderate pain. It has been in use for over 30 years and has a well-established safety profile in the general population. Since tramadol is not licensed for use in pregnancy and lactation, there is limited clinical research on its use in this patient population. A systematic review was undertaken of articles published in English before June 2011, searching Pubmed, Medline, CINAHL, Embase and Cochrane databases using the terms 'tramadol and pregnancy', 'tramadol and breastfeeding', 'tramadol and lactation', and 'tramadol and neonate'.

An informal school-based peer-led intervention for smoking prevention in adolescence (ASSIST): a cluster randomised trial.

BACKGROUND: Schools in many countries undertake programmes for smoking prevention, but systematic reviews have shown mixed evidence of their effectiveness. Most peer-led approaches have been classroom-based, and rigorous assessments are scarce. We assessed the effectiveness of a peer-led intervention that aimed to prevent smoking uptake in secondary schools. METHODS: We undertook a cluster randomised controlled trial of 10 730 students aged 12-13 years in 59 schools in England and Wales. 29 schools (5372 students) were randomly assigned by stratified block randomisation to the control group to continue their usual smoking education and 30 (5358 students) to the intervention group. The intervention (ASSIST [A Stop Smoking In Schools Trial] programme) consisted of training influential students to act as peer supporters during informal interactions outside the classroom to encourage their peers not to smoke. Follow-up was immediately after the intervention and at 1 and 2 years. Primary outcomes were smoking in the past week in both the school year group and in a group at high risk of regular smoking uptake, which was identified at baseline as occasional, experimental, or ex-smokers. Analysis was by intention to treat. This study is registered, number ISRCTN55572965. FINDINGS: The odds ratio of being a smoker in intervention compared with control schools was 0.75 (95% CI 0.55-1.01) immediately after the intervention (n=9349 students), 0.77 (0.59-0.99) at 1-year follow-up (n=9147), and 0.85 (0.72-1.01) at 2-year follow-up (n=8756). The corresponding odds ratios for the high-risk group were 0.79 (0.55-1.13 [n=3561]), 0.75 (0.56-0.99 [n=3483]), and 0.85 (0.70-1.02 [n=3294]), respectively. In a three-tier multilevel model with data from all three follow-ups, the odds of being a smoker in intervention compared with control schools was 0.78 (0.64-0.96). INTERPRETATION: The results suggest that, if implemented on a population basis, the ASSIST intervention could lead to a reduction in adolescent smoking prevalence of public-health importance.

'Topping up' methadone: an analysis of patterns of heroin use among a treatment sample of Scottish drug users.

OBJECTIVES: To determine: (a) whether Scottish drug users on methadone maintenance use heroin less frequently than their peers following other forms of drug treatment; and (b) to what extent those on methadone maintenance 'top up' with heroin. DESIGN: A cohort study followed-up for 33 months from 2001 to 2004. METHODS: Four hundred and ten interviewees who responded at all four interview sweeps, recruited as new treatment entrants from 28 drug treatment agencies across Scotland. RESULTS: Sixty-eight of the 401 interviewees had commenced an episode of methadone-maintenance treatment at the start of the study. There was no significant difference between the methadone-maintained sample and the other interviewees in their propensity to abstain from heroin use, nor was there any difference between the two groups in the mean reduction over time in their self-reported dependence on drugs. However, if the outcome measure used is the change (between baseline and 33 months) in the number of days that the interviewee reported having used heroin in the previous 3 months, the reduction in the number of days that heroin was used was significantly greater (52 days) in the methadone-maintained group than in the rest of the sample (36.4 days). This fall in the number of days of heroin use was greater still if the comparison was restricted to those who had continued on methadone-maintenance treatment, although 67.4% of those still on methadone maintenance had 'topped up' with heroin at some point in the 3 months prior to 33-month follow-up. Those on higher maintenance doses were not significantly more likely to have reduced the number of days on which they used heroin compared with those on lower doses, and those still on methadone maintenance were not more likely to have reduced their criminality (measured by the number of days on which they committed acquisitive crimes in the previous 3 months) compared with the rest of the sample. CONCLUSIONS: Methadone-maintained drug users are not more likely to achieve abstinence than drug users receiving other forms of treatment, but they are significantly more likely to achieve a reduction in the frequency of their illicit drug use; they 'top up' on methadone, but the frequency of their illicit drug use is less than that of drug users in other treatment modalities. These data confirm the value of methadone-maintenance services as part of a 'mixed economy' of services for the treatment of drug use.

An evaluation of mixed species in-situ and ex-situ feeding assays: the altered response of Asellus aquaticus and Gammarus pulex.

Mixed species feeding assays were undertaken with pollution sensitive (Gammarus pulex) and tolerant (Asellus aquaticus) macro-invertebrates during August 2003 and April 2004. The purpose of this study was to establish if a test animals' response is comparable during in-situ and ex-situ toxicity tests. Seven test sites were established along an undisclosed stream, which received leachate discharge from an unlined, disused UK landfill site. Sampling points A-B were upstream of the contamination, C was adjacent to the influx and D-G were downstream of the leachate discharge (at 100 m intervals). During the in-situ and ex-situ tests, 2-week-old male laboratory bred A. aquaticus and G. pulex were used as test animals. The animals were transplanted to the seven sampling points for the duration of the in-situ tests, whilst water samples from each site were returned to the laboratory for ex-situ testing. The results show that the animals' mortality and feeding rates followed similar trends during the in-situ and ex-situ tests, however, the animals' response was amplified during the in-situ tests. It was also observed that the effects were greater in April, compared to August that may be attributed to a higher frequency of rainfall during spring, which could have flushed a greater proportion of the contaminant load from the waste mass and as a consequence, higher levels of pollution may have leached into the stream from the landfill site. The study, therefore, concludes that in-situ toxicity tests are a more precise monitoring technique, in comparison to ex-situ assays.

Acute and sub-lethal toxicity of landfill leachate towards two aquatic macro-invertebrates: demonstrating the remediation potential of air stripping.

A specific leachate that contained 1.036 mg l(-1) of 2-chlorobiphenyl was used in the study (255 mg l(-1) COD and 133 mg l(-1) BOD5). Bench scale (20 l) air stripping trials were used to simulate on a small-scale the treatment potential of this method. Air stripping effectively reduced the leachates COD concentration. Regardless of the volume of air supplied (1-5 l of air per minute) the leachates COD reached a <50 mg l(-1) equilibrium after 96-h exposure, however, increasing the volume of air accelerated the process. In untreated leachate, the LC50 for Asellus aquaticus was 57% v/v leachate in deionised water and 5% for Gammarus pulex (96-h, static LC50 tests without nutrition and oxygen depleting conditions). After being exposed to air stripping, these values rose from 90% to below the LC50 threshold for Asellus when 1-5 l of air per minute were applied and 30-90% for Gammarus. Furthermore, in sub-lethal concentrations of air stripped leachate (leachate that had been exposed to 5-l of air per minute for 96-h) the population dynamics of both test species remained unaltered.

Subjective assessments of safety, exposure to chemicals and use of personal protection equipment in seafaring.

BACKGROUND: Most of the scientific publications from the maritime area are studies about the mortality and morbidity, while studies about the present hazards of potentially dangerous exposures are relatively rare. AIMS: To describe the seafarers' assessments of the occupational safety on board, their exposure to chemicals and the use of personal protection equipment and to identify the areas for further risk assessment and preventive measures. METHODS: A questionnaire study was carried out in 11 countries among seafarers who attended a regular health examination. RESULTS: The total number of seafarers who participated in the study was 6461 (response rate 93.7%). The occupational safety on board was assessed to be very good or good in 82%. Multivariate analyses showed that the safety was assessed as lowest among ratings, seafarers<30 years of age, work in the engine rooms and on dry cargo ships. It was highest on crude oil tankers and supply ships. Fifty-five per cent of seafarers were exposed to chemicals. Personal protection equipment to chemicals was used 'always/almost always' in 93% of the exposed. Multivariate analysis showed that the use of personal protection was highest on deck, on the largest ships, on roll-on roll-off ships and on crude oil tankers. CONCLUSION: The occupational safety and the use of personal protective equipment was assessed to be significantly different in some strata of the population and in specific working areas and types and sizes of ships.

Acute and sublethal toxicity tests to monitor the impact of leachate on an aquatic environment.

In this study, a specific landfill leachate (1200 mg l(-1) COD and 600 mg l(-1) BOD(5)) was used to develop a standardised short-term acute and longer-term sublethal ex-situ toxicity testing programme, in order to determine the potential ecological implications of leaching contaminants reaching the water table. Bioassays were undertaken with juvenile Gammarus pulex and Asellus aquaticus macro-invertebrates. Preliminary acute test variables included static and static renewed flow rates for 96-h, starved and fed specimens, and aerobic and oxygen depleting conditions. However, regardless of any test variable, the lethal concentration (LC(50)) for A. aquaticus remained at 12.3% v/v leachate in deionized water, whilst that for G. pulex was only 1%. Sublethal toxicity was judged on the basis of frequency of births and the growth rate of newly born individuals. Tests showed that even a dilution as high as 1:66- would influence the fecundity of a Gammarus population, whilst a dilution of 1:20 would affect the size of an Asellus breeding colony.

Method for efficient shape parametrization of fluid membranes and vesicles.

In this paper we describe a method for the parametrization of the shapes adopted by fluid membranes and vesicles. The method is based upon a boundary-value approach to geometry description in which smooth surfaces are produced as the solution to an elliptic partial differential equations. Shape parameters are introduced through the boundary conditions, which control the shape of the vesicle models. In combination with a model for the surface energy and a method for numerical minimization, it is shown how the method can accurately approximate the shapes of both axisymmetric and nonaxisymmetric vesicles over a wide range of control parameters. The particular value of the method lies in its ability to parametrize complicated shapes efficiently, a feature that becomes especially valuable when seeking shapes of minimal energy using direct optimization techniques.

The effectiveness of one-to-one risk communication interventions in health care: a systematic review.

OBJECTIVES: To assess whether risk-communication interventions are associated with changes in patient knowledge, attitudes, and behaviors, and to identify aspects of these interventions that modify these effects. DESIGN: Systematic review. DATA SOURCES: 96 studies from the period 1985-1996 retrieved by electronic searching of eight databases, hand searching of four journals, contacting key authors, and reference list searching. MAIN OUTCOME MEASURES: The effect size of the principal outcome was identified from each study. Outcomes measuring behavioral change were preferred; if these were not available, knowledge, anxiety, or risk perceptions were used, according to the focus of the study. Data were available to calculate the principal effect sizes for 82 of the studies. ANALYSIS: Meta-regression. RESULTS: The methodologic qualities of the studies varied. Nevertheless, risk-communication interventions generally had positive (beneficial) effects. Interventions addressing treatment choices were associated with larger effects than were those in other contexts, such as prevention or screening. Interventions using individual risk estimates were associated with larger effects than were those using more general risk information. Two design variables were identified as effect modifiers: randomized controlled trials were associated with smaller effects than other designs, and dichotomous outcomes were associated with larger effects than continuous outcomes. CONCLUSIONS: Risk communication interventions may be most productive if they include individual risk estimates in the discussion between professional and patient. Patient decisions about treatment appear more amenable to change by these interventions than attendance for screening or modification of risky behavior.

Use of mark-recapture techniques to estimate the size of hard-to-reach populations.

OBJECTIVES: To review the main problems associated with mark-recapture methods of population estimation, and to indicate some practical strategies for addressing these problems, with illustrations from a study of drug-use prevalence across Wales. METHODS: Unnamed identifier data were collected in 1994 on 2610 drug users who were in contact with various agencies across Wales: the police, drug treatment agencies, needle exchanges, probation services, and agencies reporting to the Welsh Drugs Misuse Database. RESULTS: Based on the dependency relationships between different agencies' datasets, different estimates of the 'hidden' populations (not in contact with agencies) were modelled for each county, for males and females, for injecting drug users and serious drug users, and for those under 25 and those over 25 years of age. Different models were also constructed for the same subpopulations, using different agency datasets and different criteria of overlap between them, yielding a total of 230 different models. CONCLUSIONS: The issues of sample heterogeneity and population definition are particularly intractable in mark-recapture studies. Sample heterogeneity may be partly addressed by separately modelling different subpopulations to check whether they show the same dependency relationships as the main population. Population definition may be partly addressed by restricting modelling to datasets thought to share roughly congruent population definitions.

The South Wales Miners Federation, Miners' Lung and the instrumental use of expertise, 1900-1950.

Oral history materials from the South Wales Miners' Library are used to examine the communal understandings of, collective responses to, the scourge of Miners' Lung (pneumoconiosis) in the 1920s and 1930s. Lay epidemiology in mining communities attributed an aetiological role to coaldust at a time when many experts believed miners' pulmonary disease to be bronchitic, or to be silica-induced. In their efforts to secure compensation claims for their members, union officials instrumentally used scientific expertise in a variety of forms: they contributed to epidemiological evidence; they lobbied for more government-funded research; they 'bought' experts; they duped expert witnesses; and they made sophisticated instrumental appeals to the supposed independence of favorable expert judgements. Eventually, miners' situated' 'local knowledge' became scientific orthodoxy, a success story which may be associated with the class-conscious miners' 'bump of irreverence' about expert knowledge, and with the divided character of the expert core-set, sections of which were receptive to miners' 'local knowledge' claims.

Efficient literature searching in diffuse topics: lessons from a systematic review of research on communicating risk to patients in primary care.

Using the example of communication about risk in a primary care setting, this paper puts forward a method of developing and evaluating a detailed search strategy for locating the literature for a systematic review of a 'diffuse' subject. The aim of this paper is to show how to develop a search strategy that maximizes both recall and precision while keeping search outputs manageable. Six different databases were used, namely Medline, Embase, PsychLIT, CancerLIT, Cinahl and Social Science Citation Index (SSCI). The searches were augmented by hand-searching, contacting authors, citation searching and reference lists from included papers. Other databases were searched but yielded no extra references for this subject matter. Of the 99 papers included, 80 were indexed on Medline. The Medline search strategy identified 54 of them and the remaining 26 were located on other databases. The 19 further unique references were found using the other databases and methods of retrieval. A combination of several databases must be used to maximize recall and to increase the precision of searches on individual databases, thus improving the overall efficiency of the search.

Differences in sexual risk behaviour between young men and women travelling abroad from the UK.

BACKGROUND: Identification of people who most frequently engage in sexual risk behaviour while travelling abroad would be useful for the design and targeting of health education and promotion campaigns. METHODS: Eligible participants were people living in the UK aged 18-34 years who had travelled abroad without a partner in the previous 2 years. Respondents were first screened for eligibility as part of representative face-to-face and telephone surveys by a market research company. Eligible individuals who agreed to take part then underwent a computer-assisted telephone interview. Reinterviewing continued until 400 eligible people had been contacted. We also interviewed a control group of 568 young people who had travelled abroad without a partner in the previous 2 years but who did not report a new sexual relationship during their travels. FINDINGS: One in ten of the eligible participants reported sexual intercourse with a new partner. Travellers who reported a new sexual relationship abroad were also likely to report large numbers of sexual partners at home. Of the 400 people who had a new sexual partner abroad, 300 (75%) used condoms on all occasions with the new partner. Logistic regression modelling showed differences between men and women in those factors linked to the practice of unsafe or safer sex while travelling. For men, patterns of condom use abroad with casual partners (p<.0001) reflected patterns of use at home (p<0.001), whereas for women, patterns of condom use varied according to their partners' backgrounds (p<.0001). INTERPRETATION: Condoms are widely used among young travellers, but patterns of use vary by sex. Campaigns about sexual health targeted at international travellers should continue, not least because young people who meet new sexual partners abroad may be a convenient proxy group for that minority of the population who report most sexual partners at home. Such campaigns should be designed differently for men and women.

Communication about risk: diversity among primary care professionals.

OBJECTIVE: We aimed to identify the important clinical topics and to report current practice of communication about risk in primary care. METHODS: We carried out a qualitative study using six semi-structured focus group discussions with primary care professionals. The subjects were 36 primary care professionals from general practice, practice nurse, district nurse, community psychiatric nurse and health visitor disciplines. RESULTS: All clinical topics were felt to raise issues of effective risk communication. Participants expressed concern about the lack of accessible up-to-date information and the problems of conveying information to patients. They described the circumstances and contexts in which communication varies and is difficult, and identified media and medico-legal influences and professional uncertainty as also contributing to the problems of risk communication. Specific training in risk communication was identified as an important need. CONCLUSIONS: The complexity of risk communication and diversity of influences on it will require wide-ranging interventions in order to address them. Standardized communication may be a difficult goal to attain.

Communication about risk: the responses of primary care professionals to standardizing the 'language of risk' and communication tools.

OBJECTIVE: We aimed to gauge responses of primary care professionals to standardization of the 'language of risk' and risk communication tools. METHODS: We carried out a qualitative study using six semi-structured focus group discussions. The subjects were 36 primary care professionals from general practice, practice nurse, district nurse, community psychiatric nurse and health visitor disciplines. RESULTS: Between professionals, the standardization of the language of risk was felt to have potential benefit in making professionals consistent in their appreciation of risks and communication with each other. Between professionals and patients, standardized language was thought inappropriate or insufficient because of contextual variation in communication and interpretation of risk information by patients. The use of more-detailed comparisons of risks was felt to be a potentially effective development of risk communication in practice. CONCLUSIONS: A standard language of risk communication was perceived as being potentially helpful for communication between professionals, but many respondents were sceptical about its usefulness in communication with patients.

Prediction of reactive hyperaemia in vascular pathologies using elastic porous tube model.

A mathematical model of reactive hyperaemia has been developed, in which the limb vascular system is represented by an elastic porous tube, with flow in the tube equivalent to blood flow in the arteries and large arterioles. Flow through the porous walls represents flow into the small arterioles, which respond actively by contracting as pressure throughout the system rises following occlusion release. A variety of vascular pathologies have been simulated; the effect of venous packing of the limb is to reduce the transient peak flow from normal, owing to a reduction in the pressure gradient. Occlusive disease of the femoral artery and lower arterial vessels reduces the magnitude and extends the duration of hyperaemic flow, due to a reduced pressure gradient and increased resistance. Small vessel disease reduces the hyperaemic flow, principally due to a reduction in the initial dilation of the vessels. Venous disease does not affect the initial arterial flow following occlusion release but reduces the equilibrium flow. The venous outflow increases in response to an increase in the arterio-venous pressure gradient.

Elastic porous tube model of reactive hyperaemia.

Reactive hyperaemia is the term given to the temporary increase in blood flow that follows release of an occlusion of the arterial supply. Measurement of reactive hyperaemia in the leg below the knee is useful in assessment of the vascular system, as resting flows remain unaffected even in the presence of quite severe occlusive arterial disease. An elastic porous tube representation of the vascular system is used to develop equations for the variation of the mean pressure, flow and vessel calibre in the vascular system. The tube represents the arteries and large arterioles, which respond passively to changes in pressure. Leakage through the tube walls represents flow into the small arterioles, which respond actively to the rise in pressure following release of the occlusion by constricting (the myogenic response). The capillaries are represented by rigid tubes, and the venous system is represented by a single compliant vessel. The model predicts variations in the flow, pressure and vessel calibre that are in agreement with experimental observations, and identifies that the pressure gradient is important in determining the initial transient increase in the flow following release of the occlusion. The subsequent development in the flow is governed by the small arteriolar flow, which is determined by the magnitude and duration of the myogenic response.