Biomedical subjects

A J Sutton

Publications and source records attributed to A J Sutton.

At least 19 recordsLinked to original sources

PubMed2007

An evaluation of bivariate random-effects meta-analysis for the joint synthesis of two correlated outcomes.

Often multiple outcomes are of interest in each study identified by a systematic review, and in this situation a separate univariate meta-analysis is usually applied to synthesize the evidence for each outcome independently; an alternative approach is a single multivariate meta-analysis model that utilizes any correlation between outcomes and obtains all the pooled estimates jointly. Surprisingly, multivariate meta-analysis is rarely considered in practice, so in this paper we illustrate the benefits and limitations of the approach to provide helpful insight for practitioners. We compare a bivariate random-effects meta-analysis (BRMA) to two independent univariate random-effects meta-analyses (URMA), and show how and why a BRMA is able to 'borrow strength' across outcomes. Then, on application to two examples in healthcare, we show: (i) given complete data for both outcomes in each study, BRMA is likely to produce individual pooled estimates with very similar standard errors to those from URMA; (ii) given some studies where one of the outcomes is missing at random, the 'borrowing of strength' is likely to allow BRMA to produce individual pooled estimates with noticeably smaller standard errors than those from URMA; (iii) for either complete data or missing data, BRMA will produce a more appropriate standard error of the pooled difference between outcomes as it incorporates their correlation, which is not possible using URMA; and (iv) despite its advantages, BRMA may often not be possible due to the difficulty in obtaining the within-study correlations required to fit the model. Bivariate meta-regression and further research priorities are also discussed.

Analysis of Variance↗

PubMed2006

Systematic review and meta-analysis of 12 years of endovascular abdominal aortic aneurysm repair.

BACKGROUND: Endovascular repair (ER) of abdominal aortic aneurysm (AAA) is a new technique, and reported rates of endoleak, conversion to open repair, rupture and mortality vary widely. The aim of this study was to estimate these rates from the published data, and examine how this has changed as more patients have undergone ER. METHODS: A systematic review and meta-analysis of publications identified through searches of the electronic databases EMBASE and Medline. All publications quoting endoleak, conversion to open repair, rupture and mortality rates for a series of patients undergoing ER were included. RESULTS: 163 studies pertaining to 28,862 patients undergoing ER were identified as relevant for the review and meta-analysis. The pooled estimate for operative mortality was 3.3% (95% confidence interval 2.9 to 3.6%). The pooled estimate for type 1 endoleaks was 10.5% (95% confidence interval 9.0 to 12.1%), with an annual rate of 8.4% (95% confidence interval 5.7% to 12.2%). The pooled estimate of type 2,3 and 4 endoleaks was 13.7% (95% confidence interval 12.3 to 15.3%), with an annual rate of 10.2% (95% confidence interval 7.4% to 14.1%). The pooled estimate for primary conversion to open repair was 3.8% (95% confidence interval 3.2 to 4.4%), and for secondary conversion to open repair 3.4% (95% confidence interval 2.8 to 4.2%). The pooled estimate for post-operative rupture was 1.3% (95% confidence interval 1.1 to 1.7%), with an annual rupture rate of 0.6% (95% confidence interval 0.5% to 0.8%). Multivariate meta-regression analysis showed that rates of operative mortality, post-operative rupture and total number of endoleaks all fell significantly (p<0.05) over time. CONCLUSIONS: This study demonstrates a low mortality and a gradual reduction in vascular morbidity and mortality associated with endovascular repair since it was first introduced.

Aortic Aneurysm, Abdominal↗

PubMed2006

Meta-analysis of mortality and cancer incidence among workers in the synthetic rubber-producing industry.

Production of synthetic rubber involves exposure to several potentially harmful chemicals. The authors carried out a systematic review and meta-analysis of cohort studies of workers in the rubber-producing industry. Data were obtained from computerized literature searches of several databases from their inception through December 2003. The reference lists of identified articles were inspected for further relevant articles. The authors conducted random-effects meta-analyses of log standardized mortality ratios (SMRs)/standardized incidence ratios. Heterogeneity between study results was explored through subgroup analyses and meta-regression on cohort demographic factors and study quality indicators. The authors identified 36 published articles reporting information on 31 different cohort groups. The meta-SMR was 0.86 (95% confidence interval (CI): 0.82, 0.91) for all-cause mortality (28 cohorts) and 0.94 (95% CI: 0.89, 1.01) for all malignant neoplasms (27 cohorts). Heterogeneity was observed for these endpoints and for the majority of disease-specific outcomes. Statistically significant excesses were observed for diabetes (meta-SMR=1.36, 95% CI: 1.17, 1.59) (five cohorts) and leukemia (meta-SMR=1.21, 95% CI: 1.03, 1.43) (16 cohorts), the latter particularly for persons working exclusively in nontire manufacturing (meta-SMR=1.70, 95% CI: 1.14, 2.54) (four cohorts). Excesses highlighted in previous narrative reviews were not substantiated. Interpretation of these results is complicated by substantial unexplainable heterogeneity; small excesses in specific mortality outcomes may have been disguised by the healthy worker effect.

Diabetes Mellitus↗

PubMed2006

Modelling the force of infection for hepatitis B and hepatitis C in injecting drug users in England and Wales.

BACKGROUND: Injecting drug use is a key risk factor, for several infections of public health importance, especially hepatitis B (HBV) and hepatitis C (HCV). In England and Wales, where less than 1% of the population are likely to be injecting drug users (IDUs), approximately 38% of laboratory reports of HBV, and 95% of HCV reports are attributed to injecting drug use. METHODS: Voluntary unlinked anonymous surveys have been performed on IDUs in contact with specialist agencies throughout England and Wales. Since 1990 more than 20,000 saliva samples from current IDUs have been tested for markers of infection for HBV, HCV testing has been included since 1998. The analysis here considers those IDUs tested for HBV and HCV (n = 5,682) from 1998-2003. This study derives maximum likelihood estimates of the force of infection (the rate at which susceptible IDUs acquire infection) for HBV and HCV in the IDU population and their trends over time and injecting career length. The presence of individual heterogeneity of risk behaviour and background HBV prevalence due to routes of transmission other than injecting are also considered. RESULTS: For both HBV and HCV, IDUs are at greatest risk from infection in their first year of injecting (Forces of infection in new initiates 1999-2003: HBV = 0.1076 95% C.I: 0.0840-0.1327 HCV = 0.1608 95% C.I: 0.1314-0.1942) compared to experienced IDUs (Force of infection in experienced IDUs 1999-2003: HBV = 0.0353 95% C.I: 0.0198-0.0596, HCV = 0.0526 95% C.I: 0.0310-0.0863) although independently of this there is evidence of heterogeneity of risk behaviour with a small number of IDUs at increased risk of infection. No trends in the FOI over time were detected. There was only limited evidence of background HBV infection due to factors other than injecting. CONCLUSION: The models highlight the need to increase interventions that target new initiates to injecting to reduce the transmission of blood-borne viruses. Although from the evidence here, identification of those individuals that engage in heightened at-risk behaviour may also help in planning effective interventions. The data and methods described here may provide a baseline for monitoring the success of public health interventions.

England↗

PubMed2006

Systematic review and meta-analysis of methods of diagnostic assessment for urinary incontinence.

AIMS: To evaluate the performance of all tests proposed for the diagnosis of urinary incontinence. METHODS: A systematic review and meta-analyses of the published literature of methods for diagnostic assessment of urinary incontinence. RESULTS: One hundred twenty-one papers were included in the full review [Martin et al., 2006]. The quality of reporting in the primary studies was poor which reduced the number of studies that could be included in the data analysis. The literature suggests that women with urodynamic stress incontinence (USI) can be correctly identified in primary care from clinical history alone with a sensitivity of 0.92 (95% C.I.: 0.91-0.93) and specificity of 0.56 (0.53-0.60). A clinical history for the diagnosis of detrusor overactivity (DO) was found to be 0.61 (0.57-0.65) sensitive and 0.87 (0.85-0.89) specific. Within secondary care imaging of leakage by ultrasound was found to be effective in the diagnosis of USI in women with a sensitivity of 0.89 (0.84-0.93) and specificity of 0.82 (0.73-0.89). CONCLUSIONS: Clinical interpretation of the results of the review is difficult because few studies could be synthesized and conclusions made. The published evidence suggests that a large proportion of women with USI can be correctly identified in primary care from history alone. Ultrasound offers a useful diagnostic tool which could be used prior to, and possibly instead of, multi-channel urodynamics in some circumstances. If a patient is to undergo urodynamic testing, multi-channel urodynamics is likely to give the most accurate result. Further primary studies adhering to STARD guidelines are required on commonly used tests.

Data Interpretation, Statistical↗

PubMed2006

Modelling the hepatitis B vaccination programme in prisons.

A vaccination programme offering hepatitis B (HBV) vaccine at reception into prison has been introduced into selected prisons in England and Wales. Over the coming years it is anticipated this vaccination programme will be extended. A model has been developed to assess the potential impact of the programme on the vaccination coverage of prisoners, ex-prisoners, and injecting drug users (IDUs). Under a range of coverage scenarios, the model predicts the change over time in the vaccination status of new entrants to prison, current prisoners and IDUs in the community. The model predicts that at baseline in 2012 57% of the IDU population will be vaccinated with up to 72% being vaccinated depending on the vaccination scenario implemented. These results are sensitive to the size of the IDU population in England and Wales and the average time served by an IDU during each prison visit. IDUs that do not receive HBV vaccine in the community are at increased risk from HBV infection. The HBV vaccination programme in prisons is an effective way of vaccinating this hard-to-reach population although vaccination coverage on prison reception must be increased to achieve this.

Adolescent↗

PubMed2006

How should we diagnose suspected deep-vein thrombosis?

BACKGROUND: Many different approaches are used to diagnose suspected deep-vein thrombosis (DVT), but there has been little formal comparison of strategies. AIM: To identify the most cost-effective strategy for the UK National Health Service (NHS). DESIGN: Systematic review, meta-analysis and cost-effectiveness analysis. METHODS: We identified 18 strategies and estimated the diagnostic performance of constituent tests by systematic review and meta-analysis. Outcomes of testing and treatment were estimated from published data or by an expert panel. Costs were estimated from NHS reference costs and published data. We built a decision-analysis model to estimate, for each strategy, the overall accuracy, costs, and outcomes (valued as quality-adjusted life-years, QALYs), compared to a 'no testing, no treatment' alternative. Probabilistic analysis estimated the net benefit of each strategy at varying thresholds for willingness to pay for health gain. RESULTS: At the thresholds for willingness to pay recommended by the National Institute for Clinical Excellence (20,000 pounds sterling-30,000 pounds sterling per QALY), the optimal strategy was to discharge patients with a low or intermediate Wells score and negative D-dimer, limiting ultrasound to those with a high score or positive D-dimer. Strategies using radiological testing for all patients were only cost-effective at 40,000 pound sterling per QALY or more. DISCUSSION: The optimal strategy for DVT diagnosis is to use ultrasound selectively in patients with a high clinical risk or positive D-dimer. Radiological testing for all patients does not appear to be a cost-effective use of health service resources.

Cost-Benefit Analysis↗

PubMed2006

Meta-analysis of plethysmography and rheography in the diagnosis of deep vein thrombosis.

BACKGROUND: Plethysmography and rheography techniques have been widely studied as diagnostic tests for deep vein thrombosis (DVT). This study aimed to systematically review the accuracy of these tests for diagnosing clinically suspected DVT. METHODS: The following databases were searched: Medline, EMBASE, CINAHL, Web of Science, Cochrane Database of Systematic Reviews, Cochrane Controlled Trials Register, Database of Reviews of Effectiveness, the ACP Journal Club (1966 to 2004), and citation lists of retrieved articles. Studies that compared plethysmography or rheography to a reference standard of ultrasound or contrast venography were selected. Standardised data were extracted and study quality determined against validated criteria. Data were analysed by random effects meta-analysis and meta-regression. RESULTS: The meta-analysis included 78 studies, reporting 82 patient cohorts. Sensitivity and specificity (95% CI) were: 75% (73% to 77%) and 90% (89% to 91%) for impedance plethysmography, 83% (81% to 85%) and 81% (79% to 82%) for strain-gauge plethysmography, 85% (79% to 90%) and 91% (81% to 95%) for air plethysmography, 91% (87% to 94%) and 71% (66% to 75%) for light-reflex rheography, and 86% (83% to 89%) and 93% (91% to 95%) for phleborheography. Meta-regression was limited by poor reporting of studies. There was some evidence that diagnostic performance depended on the proportion of males in the cohort and reporting of study setting. CONCLUSIONS: Although plethysmography and rheography techniques add diagnostic value, they have inadequate diagnostic performance to act as a stand-alone test in DVT diagnosis. Evaluation of their role in combination with other tests, or standardised clinical assessment, is required.

Cohort Studies↗

PubMed2006

Consistency in decision making by research ethics committees: a controlled comparison.

There has been longstanding interest in the consistency of decisions made by research ethics committees (RECs) in the UK, but most of the evidence has come from single studies submitted to multiple committees. A systematic comparison was carried out of the decisions made on 18 purposively selected applications, each of which was reviewed independently by three different RECs in a single strategic health authority. Decisions on 11 applications were consistent, but disparities were found among RECs on decisions on seven applications. An analysis of the agreement between decisions of RECs yielded an overall measure of agreement of kappa = 0.286 (95% confidence interval -0.06 to 0.73), indicating a level of agreement that, although probably better than chance, may be described as "slight". The small sample size limits the robustness of these findings. Further research on reasons for inconsistencies in decision making between RECs, and on the importance of such inconsistencies for a range of arguments, is needed.

Decision Making↗

PubMed2006

Systematic review and evaluation of methods of assessing urinary incontinence.

OBJECTIVES: To identify and synthesise studies of diagnostic processes of urinary incontinence and to construct an economic model to examine the cost-effectiveness of simple, commonly used primary care tests. DATA SOURCES: The electronic databases MEDLINE (1966--2002), CINAHL (1982--2002) and EMBASE (1980--2002). REVIEW METHODS: Studies were selected and assessed using the Quality Assessment of Diagnostic Studies (QUADAS) tool. Studies that reported the results of applying the same diagnostic procedure using the same threshold value (cut-off) were pooled using a random effects meta-analysis model to produce pooled estimates of sensitivity, specificity and diagnostic odds ratio together with 95% confidence intervals. RESULTS: In total, 6009 papers were identified from the literature search, of which 129 were deemed relevant for inclusion in the review, and these papers compared two or more diagnostic techniques. The gold-standard diagnostic test for urinary incontinence with which each reference test was compared was multichannel urodynamics. In general, reporting in the primary studies was poor; there was a lack of literature in the key clinical areas and minimal literature dealing with diagnosis in men. Only a limited number of studies could be combined or synthesised, providing the following results when compared with multichannel urodynamics. A clinical history for diagnosing urodynamic stress incontinence (USI) in women was found to have a sensitivity of 0.92 and specificity of 0.56 and for detrusor overactivity (DO) a sensitivity of 0.61 and specificity of 0.87. For validated scales, question 3 of the Urogenital Distress Inventory was found to have a sensitivity of 0.88 and specificity of 0.60. Seven studies compared a pad test with multichannel urodynamics; however, four different pad tests were studied and therefore it was difficult to draw any conclusions about diagnostic accuracy. Of the four studies comparing urinary diary with multichannel urodynamics, only one presented data in a format that allowed sensitivity and specificity to be calculated. Their reported values of 0.88 and 0.83 suggest that a urinary diary may be effective in the diagnosis of DO in women. Examination of the incremental cost-effectiveness of three primary care tests used in addition to history found that the diary had the lowest cost-effectiveness ratio of between pound 35 and pound 77 per extra unit of effectiveness (or case diagnosed). Imaging by ultrasound to determine leakage was found to be effective in the diagnosis of USI in women, with a sensitivity of 0.94 and specificity of 0.83. CONCLUSIONS: This is the first systematic review of methods for diagnosing urinary incontinence. As reporting of the primary studies was poor, clinical interpretation was often difficult because few studies could be synthesised and conclusions made. The report found that a large proportion of women with USI can be correctly diagnosed in primary care from clinical history alone. On the basis of diagnosis the diary appears to be the most cost-effective of the three primary care tests (diary, pad test and validated scales) used in addition to clinical history. Ultrasound imaging may offer a valuable alternative to urodynamic investigation. The clinical stress test is effective in the diagnosis of USI. Adaptation of such a test so that it could be performed in primary care with a naturally filled bladder may prove clinically useful. If a patient is to undergo an invasive urodynamic procedure, multichannel urodynamics is likely to give the most accurate result in a secondary care setting. There is a dearth of literature on the diagnosis of urinary incontinence in men, with no studies meeting the study criteria for data extraction in the diagnosis of bladder outlet obstruction. There is a need for large-scale, high-quality primary studies evaluating the use of a number of diagnostic methods in a primary care setting to be undertaken so that the results of this systematic review can be verified or not. Such studies should include not only an assessment of clinical effectiveness, in this case diagnostic accuracy, but also an assessment of costs and quality of life/satisfaction to inform future health policy decisions. Studies carried out should be reported to a better standard. The recommendations of the Standards for Reporting Diagnostic Accuracy (STARD) initiative should be followed to ensure the accuracy and completeness of reporting design and results.

Diagnostic Tests, Routine↗

PubMed2005

Modelling the impact of prison vaccination on hepatitis B transmission within the injecting drug user population of England and Wales.

A vaccination programme offering hepatitis B (HBV) vaccine at reception into prison has been introduced into selected prisons in England and Wales. The work here considers the impact of prison vaccination on the incidence and prevalence of hepatitis B virus (HBV) in the injecting drug user (IDU) population of England and Wales. A dynamic model of the transmission of HBV in IDUs is developed with key model assumptions and parameters being subject to sensitivity analyses. The base case model (that assumes that the vaccination coverage on prison reception is 5% in 2002, 10% in 2003 and then increases linearly up to 50% of prison receptions being vaccinated by 2006) predicts that the incidence of HBV in IDUs might be reduced by almost 80% in 12 years, and the HBV prevalence (IDUs ever infected by HBV) may be reduced from approximately 18% in 2002 to 7% in 2015. The model presented here demonstrates that HBV vaccination on prison reception can have a significant impact on the prevalence and incidence of HBV in the IDU population over time.

Adolescent↗

PubMed2005

Consumption of mannan-binding lectin during abdominal aortic aneurysm repair.

OBJECTIVE: Patients undergoing abdominal aortic aneurysm (AAA) repair are exposed to an ischaemia-reperfusion injury (IRI), which is in part mediated by complement activation. We investigated the role of the novel lectin pathway of complement during IRI in patients undergoing AAA repair. METHODS: Patients undergoing elective open infrarenal AAA repair had systemic blood samples taken at induction of anaesthesia, prior to aortic clamping, prior to aortic declamping and at reperfusion. Control patients undergoing major abdominal surgery were also included. Plasma was assayed for levels of mannan-binding lectin (MBL) using ELISA techniques. Consumption of plasma MBL was used as a measure of lectin pathway activation. RESULTS: Twenty-three patients undergoing AAA repair and eight control patients were recruited. No lectin pathway activation could be demonstrated in the control patients. AAA patients experienced a mean decrease in plasma MBL levels of 41% representing significant lectin pathway activation (p = 0.003). CONCLUSION: Consumption of MBL occurs during AAA repair, suggesting an important role for the lectin pathway in IRI. Specific transient inhibition of lectin pathway activity could be of significant therapeutic value in patients undergoing open surgical AAA repair.

Aged↗

PubMed2005

The cost-effectiveness of influenza vaccination of healthy adults 50-64 years of age.

Influenza can cause significant morbidity and mortality. Influenza vaccination is an effective and safe strategy in the prevention of influenza. Currently the National Health Service (NHS) vaccinates 'at-risk' individuals only. This definition includes everyone over 65 years of age but excludes individuals 50-64 years of age unless they have an additional risk factor, such as underlying heart disease or lung disease. In order to examine the cost-effectiveness of an extension of the vaccination policy to include this age group we constructed an economic model to estimate the costs and benefits of vaccination from both a health service and a societal perspective. Data to populate the model was obtained from the literature and the outcome measure used was the quality adjusted life year (QALY). Influenza vaccination prevented an estimated 4508 cases (95% CI: 2431-7606) per 100,000 vaccinees per influenza season for a net cost to the NHS of pound653,221 (95% CI: 354,575-1,072,257). The net cost increased to pound1,139,069 (95% CI 27,052-2,030,473) when non-NHS costs were included and the estimated cost-per-QALY were pound6174 and pound10,766 for NHS and all costs respectively. Extension of the current immunisation policy has the potential to generate a significant health benefit at a comparatively low cost.

Cost-Benefit Analysis↗

PubMed2005

Variation in the diagnostic performance of D-dimer for suspected deep vein thrombosis.

BACKGROUND: Numerous studies have evaluated the accuracy of D-dimer in diagnosing suspected deep vein thrombosis (DVT), but results are conflicting. AIM: To overview estimates of the diagnostic accuracy of D-dimer and identify causes of variation. DESIGN: Systematic review, meta-analysis and meta-regression. METHODS: We searched Medline, EMBASE, CINAHL, Web of Science, Cochrane Database of Systematic Reviews, Cochrane Controlled Trials Register, Database of Reviews of Effectiveness, the ACP Journal Club, citation lists, and contacted manufacturers. We selected studies that compared D-dimer to a reference standard in patients with suspected DVT. Data were analysed by random effects meta-analysis and meta-regression. RESULTS: We included 97 studies reporting 198 assays in 99 different patient groups. Overall estimated sensitivity and specificity of D-dimer were 90.5% and 54.7%, but both estimates were subject to significant heterogeneity (p < 0.001). Meta-regression identified that some heterogeneity was explained by study setting, exclusion criteria, whether recruitment was consecutive or the study prospective, whether D-dimer and the reference standard were measured blind, and whether the D-dimer threshold was determined a priori. Sensitivity and specificity also varied between ELISA (94% and 45% respectively), latex (89% and 55%) and whole blood agglutination assays (87% and 68%). Sensitivity was higher for proximal than distal DVT. Specificity was dependent upon whether clinical probability of DVT was high (specificity 51%), intermediate (67%) or low (78%). DISCUSSION: D-dimer has good sensitivity, but poor specificity, for DVT. Estimates are subject to substantial heterogeneity from various sources. D-dimer specificity appears to be strongly dependent upon the pre-test clinical probability of DVT.

Antifibrinolytic Agents↗

PubMed2005

Are ethnic differences in lung function explained by chest size?

BACKGROUND: Ethnic differences in lung function (LF) are recognised in adults and children. Most prediction equations for LF are derived from whites, so non-whites are at risk of erroneous assessment. It was hypothesised that differences in chest dimensions would explain differences in LF between Asian (Indian) and white schoolchildren. AIMS: To quantify the impact of chest dimensions on LF, which would inform our understanding of ethnic differences that have implications for health care. METHODS: Children aged 6-11 were studied in school. A questionnaire provided information on ethnicity and respiratory health. Spirometry was used to record FVC, FEV1, FEF25-75, and PEF. Weight, height, sitting height, and chest dimensions (chest height, circumference, antero-posterior and transverse diameters) were measured. RESULTS: Data were obtained from 294 healthy children. Standing height was the most important predictor of LF. Ethnicity was an independent predictor for all LF measures except PEF, where the effect was marginal. FVC in whites was 13.4% bigger than in Asians of the same height, and the FEV1 was 10.6% greater in whites. The influence of chest dimensions on lung function was trivial. Body mass index was smaller in Asians but did not explain differences in LF. CONCLUSIONS: Differences in chest dimensions did not explain the substantial effect of ethnicity on LF. Mechanisms whereby ethnicity exerts its influence may include differences in inspiratory muscle strength or lung compliance but remain speculative. Nevertheless it remains imperative that ethnic differences are recognised when interpreting LF tests.

Anthropometry↗

PubMed2004

Interleukin 6 production during abdominal aortic aneurysm repair arises from the gastrointestinal tract and not the legs.

BACKGROUND: Abdominal aortic aneurysm (AAA) repair is associated with a systemic inflammatory response. This inflammatory response probably arises as a result of an ischaemia-reperfusion injury to the legs and gastrointestinal tract. In this study the relative contributions of these areas to the inflammatory response were assessed during elective AAA repair. METHODS: Blood was sampled from the femoral vein, portal vein and radial artery of 14 patients undergoing elective AAA repair at five time points during the procedure. Plasma was snap-frozen for subsequent batch analysis of interleukin (IL) 6. RESULTS: The plasma IL-6 concentration rose steadily throughout the procedure at all three locations. The increase in plasma IL-6 was significantly greater in the portal vein than in the radial artery during ischaemia (P = 0.020). The plasma IL-6 concentration was also significantly higher in the portal vein than in the femoral vein (P < 0.001) and radial artery (P < 0.001) during reperfusion. There were no significant differences between radial artery and femoral vein IL-6 levels at any time point. CONCLUSION: Ischaemia and reperfusion during AAA repair were associated with a marked increase in IL-6 concentration in the portal vein, suggesting that IL-6 was produced by the gastrointestinal tract.

Analysis of Variance↗

PubMed2004

Accuracy of a 12-lead electrocardiogram in screening patients with suspected heart failure for open access echocardiography: a systematic review and meta-analysis.

AIM: The aim of this study was to examine the usefulness of 12-lead electrocardiogram in screening patients with suspected heart failure for open access echocardiography. We carried out a systematic review and meta-analysis of published observational studies. Published studies were identified in the Medline and Embase databases, this was supplemented by key texts, personal reference collections and examining the cited references in the above sources. English language articles in which patients were referred from primary care with a presumptive diagnosis of heart failure to an open access echocardiography service were reviewed. We included studies that reported both electrocardiography findings and echocardiography as a reference standard. Primary outcome measures were sensitivity and specificity, meta-analysed simultaneously to produce a Summary Receiver Operating Characteristic (SROC) curve. RESULTS: Four trials were identified which satisfied the inclusion criteria, including 1419 people with a potential diagnosis of heart failure referred for open access echocardiography. Estimates of sensitivity and specificity varied greatly in individual studies. The area under the SROC curve was 0.84 (95% Cl: 0.33 to 1.00). CONCLUSION: A 12-lead electrocardiogram is an inadequate screening tool for identifying patients with suspected heart failure who require echocardiography. Further research is required to determine the usefulness of other screening strategies including B-type natriuretic peptide in screening patients with suspected heart failure who need referral for open access echocardiography.

Electrocardiography↗

PubMed2004

The post-operative mortality of ruptured abdominal aortic aneurysm repair.

INTRODUCTION: Late peri-operative death after ruptured abdominal aortic aneurysm (RAAA) repair is usually due to multiple-organ failure. The aim of this study was to identify any factors that are associated with mortality in this group of patients. METHODS: A retrospective case-note review of a single decade's operative experience of RAAA repair in a single centre. Only those patients with confirmed rupture at laparotomy were included. Sixty-three pre- intra- and post-operative variables were recorded where possible for each patient who survived surgery and the initial 24-hours post-operatively. Multi-variate analysis was performed using stepwise logistic regression. The P-POSSUM, RAAA-POSSUM, RAAA-POSSUM (physiology only), V-POSSUM, and V-POSSUM (physiology only) models were all compared to determine how each performed in these patients. RESULTS: Two hundred and twenty-three cases of confirmed RAAA were identified, of whom 139 survived the operation and initial 24-hours post-operatively. In-hospital mortality in this group of patients was 32.4%. Variables significantly associated with mortality after multi-variate analysis, were low intra-operative systolic blood pressure, the presence of a consultant anaesthetist at the initial operation and the development of cardiac, renal or gastro-intestinal complications. All POSSUM models except the V-POSSUM and P-POSSUM (physiology only) models demonstrated no significant lack of fit in this dataset. DISCUSSION: Factors associated with delayed peri-operative death after RAAA are not the same as those previously found to be associated with overall peri-operative mortality after RAAA repair.

Aged↗