Meta-analysis and systematic review of the relationship between surgeon annual caseload and mortality for elective open abdominal aortic aneurysm repairs

Decreasing prevalence of centers meeting the Society for Vascular Surgery abdominal aortic aneurysm guidelines in the United States

OBJECTIVE

Based on data supporting a volume-outcome relationship in elective aortic aneurysm repair, the Society of Vascular Surgery (SVS) guidelines recommend that endovascular aortic repair (EVAR) be localized to centers that perform ≥10 operations annually and have a perioperative mortality and conversion-to-open rate of ≤2% and that open aortic repair (OAR) be localized to centers that perform ≥10 open aortic operations annually and have a perioperative mortality ≤5%. However, the number and distribution of centers meeting the SVS criteria remains unclear. This study aimed to estimate the temporal trends and geographic distribution of Centers Meeting the SVS Aortic Guidelines (CMAG) in the United States.

METHODS

The SVS Vascular Quality Initiative was queried for all OAR, aortic bypasses, and EVAR from 2011 to 2019. Annual OAR and EVAR volume, 30-day elective operative mortality for OAR or EVAR, and EVAR conversion-to-open rate for all centers were calculated. The SVS guidelines for OAR and EVAR, individually and combined, were applied to each institution leading to a CMAG designation. The proportion of CMAGs by region (West, Midwest, South, and Northeast) were compared by year using a χ2 test. Temporal trends were estimated using a multivariable logistic regression for CMAG, adjusting by region.

RESULTS

Overall, 67,865 patients (49,264 EVAR; 11,010 OAR; 7591 aortic bypasses) at 336 institutions were examined. The proportion of EVAR CMAGs increased nationally by 1.7% annually from 51.6% (n = 33/64) in 2011 to 67.1% (n = 190/283) in 2019 (β = .05; 95% confidence interval [CI], 0.01-0.09; P = .02). The proportion of EVAR CMAGs across regions ranged from 27.3% to 66.7% in 2011 to 63.9% to 72.9% in 2019. In contrast, the proportion of OAR CMAGs has decreased nationally by 1.8% annually from 32.8% (n = 21/64) in 2011 to 16.3% (n = 46/283) in 2019 (β = -.14; 95% CI, -0.19 to -0.10; P < .01). Combined EVAR and OAR CMAGs were even less frequent and decreased by 1.5% annually from 26.6% (n = 17/64) in 2011 to 13.1% (n = 37/283) in 2019 (β = -.12; 95% CI, -0.17 to -0.07; P < .01). In 2019, there was no significant difference in regional variation of the proportion of combined EVAR and OAR CMAGs (P = .82).

CONCLUSIONS

Although an increasing proportion of institutions nationally meet the SVS guidelines for EVAR, a smaller proportion meet them for OAR, with a concerning downward trend. These data question whether we can safely offer OAR at most institutions, have important implications about sufficient OAR exposure for trainees, and support regionalization of OAR.

Benchmarking a Center of Excellence in Vascular Surgery: Using Acute Physiology and Chronic Health Evaluation II to Validate Outcomes in a Tertiary Care Institute

OBJECTIVE

The Society of Vascular Surgery (SVS) has made it a top priority to implement verification of vascular "centers of excellence". Our institutional aortic network was established in 2008 in order to standardize care of patients with suspected acute aortic pathology. The implementation and success of this program has been previously reported. We sought to use our experience as a benchmark for which to develop prognostic modeling to quantify clinical status upon admission and help predict outcomes. Our objective was to validate the Acute Physiology and Chronic Health Evaluation (APACHE) II scoring system using a cohort of aortic emergencies transferred by an organized transfer network.

METHOD

This was a retrospective, single institution review of patients transferred through an institutional aortic network for acute aortic pathology from 2017-2018. Demographics, comorbidities, aortic diagnosis, APACHE II score, as well as 30-day mortality were recorded. Associations with 30-day mortality were evaluated using two-sample t-tests, ANOVA models, Pearson chi-square tests and Fisher exact tests. Receiver operating characteristic (ROC) curves were fit overall and by pathology to predict 30-day mortality by Apache II total score.

RESULTS

There were 395 consecutive transfers were identified. The mean age was 64.7 years. Diagnoses included Type A Dissection (n = 134), Type B (n = 81), Aortic Aneurysm (n = 122), and PAU/IMH (n = 27). Mean APACHE II score on arrival was 12. Overall there were 53 deaths (13.4%) in the cohort. Patients that died had significantly higher Apache II total scores (11.3 vs 16.5, P < .001). The area under the receiver operator characteristic (ROC) curve (AUC) was .66 for the full cohort, indicating a poor clinical prediction test.

CONCLUSION

APACHE II score is a poor predictor of 30-day mortality in a large transfer network accepting all aortic emergencies. The authors believe further refining a prognostic model for diverse population will not only help in predicting outcomes but to objectively quantify illness severity in order to have a basis for comparison among institutions and verification of "centers of excellence".

The role of big data, risk prediction, simulation, and centralization for emergency vascular problems: Lessons learned and future directions

Vascular specialists remain in high demand in current practice and commonly oversee care delivery for a variety of clinical emergencies. Accordingly, the contemporary vascular surgeon must be facile with treating a spectrum of problems, including a complex, heterogeneous group of acute arteriovenous thromboembolic and bleeding diatheses. It has been documented previously that there are substantial current workforce limitations placing constraints on vascular surgical care provision. Moreover, with the aging at-risk population, there remains a considerable national urgency to improve timely diagnoses, specialty consultation, and appropriate transfer of patients to centers of excellence capable of providing a comprehensive compendium of emergency vascular services. Clinical decision aids, simulation training, and regionalization of nonelective vascular problems are all strategies that have been increasingly recognized to address these service gaps. Notably, clinical research in vascular surgery has traditionally focused on identification of patient- and procedure-related factors that influence outcomes by using resource-intensive causal inference methodology. By comparison, large data sets have only more recently been recognized to be a valuable tool that can provide heuristic algorithms to address more complex health care problems. Such data can be manipulated to generate clinical risk scores and decision aids, as well as robust outcome descriptions, which stand to inform stakeholders regarding best practice. The purpose of this review was to provide a robust overview of the lessons derived from the application of big data, risk prediction, and simulation in the management of vascular emergencies.

Incidence and Outcomes of Abdominal Aortic Aneurysm Repair in New Zealand from 2001 to 2021

Purpose: The burden of abdominal aortic aneurysms (AAA) has changed in the last 20 years but is still considered to be a major cause of cardiovascular mortality. The introduction of endovascular aortic repair (EVAR) and improved peri-operative care has resulted in a steady improvement in both outcomes and long-term survival. The objective of this study was to identify the burden of AAA disease by analysing AAA-related hospitalisations and deaths. Methodology: All AAA-related hospitalisations in NZ from January 2001 to December 2021 were identified from the National Minimum Dataset, and mortality data were obtained from the NZ Mortality Collection dataset from January 2001 to December 2018. Data was analysed for patient characteristics including deprivation index, repair methods and 30-day outcomes. Results: From 2001 to 2021, 14,436 patients with an intact AAA were identified with a mean age of 75.1 years (SD 9.7 years), and 4100 (28%) were females. From 2001 to 2018, there were 5000 ruptured AAA with a mean age of 77.8 (SD 9.4), and 1676 (33%) were females. The rate of hospitalisations related to AAA has decreased from 43.7 per 100,000 in 2001 to 15.4 per 100,000 in 2018. There was a higher proportion of rupture AAA in patients living in more deprived areas. The use of EVAR for intact AAA repair has increased from 18.1% in 2001 to 64.3% in 2021. The proportion of octogenarians undergoing intact AAA repair has increased from 16.2% in 2001 to 28.4% in 2021. The 30-day mortality for intact AAA repair has declined from 5.8% in 2001 to 1.7% in 2021; however, it has remained unchanged for ruptured AAA repair at 31.6% across the same period. Conclusions: This study highlights that the incidence of AAA has declined in the last two decades. The mortality has improved for patients who had a planned repair. Understanding the contemporary burden of AAA is paramount to improve access to health, reduce variation in outcomes and promote surgical quality improvement.

The Implications of Surgeon Case Volume and Hospital Volume on Outcomes of Aortobifemoral Bypasses in Obese Patients

BACKGROUND

Aortobifemoral (ABF) bypass is the gold standard for treating symptomatic aortoiliac occlusive disease. In the era of heightened interest in the length of stay (LOS) for surgical patients, this study aims to investigate the association of obesity with postoperative outcomes at the patient, hospital, and at surgeon levels.

METHODS

This study utilized the Society of Vascular Surgery (SVS) Vascular Quality Initiative (VQI) suprainguinal bypass database from 2003-2021. The selected study cohort was divided into obese patients (BMI ≥30) (Group I) and non-obese patients (BMI <30) (Group II). Primary outcomes of the study included mortality, operative time, and postoperative LOS. Univariate and multivariate logistic regression analyses were performed to study the outcomes of ABF bypass in Group I. Operative time, and postoperative LOS were transformed into binary values by median split for regression analysis. A p-value of ≤ 0.05 was deemed statistically significant in all the analyses of this study.

RESULTS

The study cohort consisted of 5,392 patients. In this population, 1,093 were obese (Group I), and 4,299 were non-obese (Group II). Group I was found to have more females with higher rates of comorbid conditions, including hypertension, diabetes mellitus, and congestive heart failure. Patients in Group I had increased odds of prolonged operative time (≥ 250 mins) and an increased LOS (≥6 days). Patients in this Group also had a higher chance of intraoperative blood loss, prolonged intubation, and required vasopressors postoperatively. There was also an increased odds of postoperative decline in renal function in the obese population. Patients with prior history of CAD, hypertension, diabetes mellitus, and urgent or emergent procedures were found to be risk factors for LOS>6 days in obese patients. An increase in the surgeons' case volume was associated with lesser odds of operative time ≥ 250 mins; however, no significant impact was found on postoperative LOS. Hospitals where ≥ 25% ABF bypasses were performed on obese patients were also more likely to have LOS <6 days after ABF operations, compared to hospitals where <25% of ABF bypasses were performed on obese patients. Patients undergoing ABF for CLTI or acute limb ischemia had longer LOS and increased operative time.

CONCLUSION

ABF bypass in obese patients is associated with prolonged operative times and longer LOS than in non-obese patients. Obese patients operated by surgeons with more cases of ABF bypasses have shorter operative times. An increasing hospital's obese patient proportion was related to decreased LOS. These findings support the known volume-outcome relationship that with a higher surgeon case volume and increased proportion of obese patients in a hospital, there is an improvement in outcomes of obese patients undergoing ABF bypass.

The failing endograft-A systematic review of aortic graft explants and associated outcomes

OBJECTIVE

The prominent use of endovascular stent grafts in the management of abdominal aortic aneurysms is associated with increased descriptions of late complications such as graft infection and endoleaks, which can confer significant morbidity and mortality. Failed endovascular management of late complications often requires open conversion and graft explantation. This systematic review sought to highlight the peri- and post-operative course of patients undergoing aortic graft explants to inform readers of the associated morbidity and mortality of patients undergoing this procedure.

METHODS

The review was conducted in accordance with PRISMA guidelines. A search of the PubMed, Google Scholar and Ovid MEDLINE databases from January 1995 to April 2021 was performed with a combination of MeSH terms pertaining to endovascular aneurysm repair and open conversion. Articles were screened and included based on pre-determined selection criteria.

RESULTS

A total of 818 studies were identified, with 41 meeting inclusion criteria. These studies examined a total of 1324 patients, 84.3% of whom were male with a mean age of 74 years at explantation. Mean time to graft explantation was 36 months, with a mean aneurysm size of 66 mm. The majority of aortic explants were performed for persistent endoleaks (68%), and 10% for infection. There was high morbidity with the procedure, with high rates of post-operative complications (mean, 37%) and 30-day mortality (11%). The most common complications included renal (15%), respiratory (12%) and cardiac (9%). Most explanted grafts were first-generation endografts. Morbidity and mortality rates were reduced in patients undergoing elective explants compared to emergent procedures (3.3% compared to 43.4%).

CONCLUSION

Aortic graft explant remains a highly co-morbid procedure, with high rates of peri- and post-operative complications and mortality. The number of explant procedures reported over the past 25 years has increased, reflecting the prominent use of EVAR in the management of AAAs. Whilst remaining a highly co-morbid procedure, patients undergoing elective explants had markedly reduced rates of mortality and morbidity compared to emergent explants. Thus, clinical focus should be on identifying patients who require graft explantation early to perform these procedures in an elective setting.

Open versus Endovascular Abdominal Aortic Aneurysm Repair in the Australian Private Sector Over Twenty Years

PURPOSE

Over the past two decades, the proliferation of endovascular surgery has changed the approach to abdominal aortic aneurysm (AAA) repair. In Australia, close to two-thirds of surgical procedures are performed in the private healthcare system. We aimed to describe the trends in AAA repair in the Australian private sector throughout the early 21st century.

MATERIALS AND METHODS

Medicare Benefits Schedule (MBS) statistics were accessed to determine the number of infrarenal open AAA repair (OAR) and endovascular AAA repair (EVAR) procedures performed between January 2000 and December 2019. Population data were extracted from the Australian Bureau of Statistics and used to calculate incidence per 100,000 population. Further analysis was performed according to age, gender, and state.

RESULTS

During the study period, 13,193 (67.0%) EVARs and 6504 (33.0%) OARs were performed in the Australian private sector. OARs fell from 70.5% (n=567) of AAA repairs in 2000 to 15.7% (n=237) in 2019, while EVARs rose from 29.5% (n=151) to 84.3% (n=808). The frequency of EVAR surpassed OAR in 2004. The overall incidence of AAA repair varied minimally over the time period (range: 4.9-6.5 per 100,000 adults per year). AAA repair was more common in males than females (9.7 vs 1.7 per 100,000 population) and more common in older age groups. There was a 4-fold increase in EVAR among males older than 85 years (12.8-57.4 per 100,000 population), the largest rise of any group. The overall EVAR:OAR ratio increased from 0.4 to 5.4. There were considerable state-based discrepancies.

CONCLUSION

The landscape of AAA repair in Australian private sector has drastically changed with a clear preference toward EVAR. EVAR saw increased use across all genders, age groups and states, despite stable rates of AAA surgery. Further research is necessary to compare our findings to national trends in the Australian public sector.

Configuration of vascular services: a multiple methods research programme

Background

Vascular services is changing rapidly, having emerged as a new specialty with its own training and specialised techniques. This has resulted in the need for reconfiguration of services to provide adequate specialist provision and accessible and equitable services.

Objectives

To identify the effects of service configuration on practice, resource use and outcomes. To model potential changes in configuration. To identify and/or develop electronic data collection tools for collecting patient-reported outcome measures and other clinical information. To evaluate patient preferences for aspects of services other than health-related quality of life.

Design

This was a multiple methods study comprising multiple systematic literature reviews; the development of a new outcome measure for users of vascular services (the electronic Personal Assessment Questionnaire – Vascular) based on the reviews, qualitative studies and psychometric evaluation; a trade-off exercise to measure process utilities; Hospital Episode Statistics analysis; and the development of individual disease models and a metamodel of service configuration.

Setting

Specialist vascular inpatient services in England.

Data sources

Modelling and Hospital Episode Statistics analysis for all vascular inpatients in England from 2006 to 2018. Qualitative studies and electronic Personal Assessment Questionnaire – Vascular evaluation with vascular patients from the Sheffield area. The trade-off studies were based on a societal sample from across England.

Interventions

The data analysis, preference studies and modelling explored the effect of different potential arrangements for service provision on the resource use, workload and outcomes for all interventions in the three main areas of inpatient vascular treatment: peripheral arterial disease, abdominal aortic aneurysm and carotid artery disease. The electronic Personal Assessment Questionnaire – Vascular was evaluated as a potential tool for clinical data collection and outcome monitoring.

Main outcome measures

Systematic reviews assessed quality and psychometric properties of published outcome measures for vascular disease and the relationship between volume and outcome in vascular services. The electronic Personal Assessment Questionnaire – Vascular development considered face and construct validity, test–retest reliability and responsiveness. Models were validated using case studies from previous reconfigurations and comparisons with Hospital Episode Statistics data. Preference studies resulted in estimates of process utilities for aneurysm treatment and for travelling distances to access services.

Results

Systematic reviews provided evidence of an association between increasing volume of activity and improved outcomes for peripheral arterial disease, abdominal aortic aneurysm and carotid artery disease. Reviews of existing patient-reported outcome measures did not identify suitable condition-specific tools for incorporation in the electronic Personal Assessment Questionnaire – Vascular. Reviews of qualitative evidence, primary qualitative studies and a Delphi exercise identified the issues to be incorporated into the electronic Personal Assessment Questionnaire – Vascular, resulting in a questionnaire with one generic and three disease-specific domains. After initial item reduction, the final version has 55 items in eight scales and has acceptable psychometric properties. The preference studies showed strong preference for endovascular abdominal aortic aneurysm treatment (willingness to trade up to 0.135 quality-adjusted life-years) and for local services (up to 0.631 quality-adjusted life-years). A simulation model with a web-based interface was developed, incorporating disease-specific models for abdominal aortic aneurysm, peripheral arterial disease and carotid artery disease. This predicts the effects of specified reconfigurations on workload, resource use, outcomes and cost-effectiveness. Initial exploration suggested that further reconfiguration of services in England to accomplish high-volume centres would result in improved outcomes, within the bounds of cost-effectiveness usually considered acceptable in the NHS.

Limitations

The major source of evidence to populate the models was Hospital Episode Statistics data, which have limitations owing to the complexity of the data, deficiencies in the coding systems and variations in coding practice. The studies were not able to address all of the potential barriers to change where vascular services are not compliant with current NHS recommendations.

Conclusions

There is evidence of potential for improvement in the clinical effectiveness and cost-effectiveness of vascular services through further centralisation of sites where major vascular procedures are undertaken. Preferences for local services are strong, and this may be addressed through more integrated services, with a range of services being provided more locally. The use of a web-based tool for the collection of clinical data and patient-reported outcome measures is feasible and can provide outcome data for clinical use and service evaluation.

Future work

Further evaluation of the economic models in real-world situations where local vascular service reconfiguration is under consideration and of the barriers to change where vascular services do not meet NHS recommendations for service configuration is needed. Further work on the electronic Personal Assessment Questionnaire – Vascular is required to assess its acceptability and usefulness in clinical practice and to develop appropriate report formats for clinical use and service evaluation. Further studies to assess the implications of including non-health-related preferences for care processes, and location of services, in calculations of cost-effectiveness are required.

Study registration

This study is registered as PROSPERO CRD42016042570, CRD42016042573, CRD42016042574, CRD42016042576, CRD42016042575, CRD42014014850, CRD42015023877 and CRD42015024820.

Funding

This project was funded by the National Institute for Health Research (NIHR) Programme Grants for Applied Research programme and will be published in full in Programme Grants for Applied Research; Vol. 9, No. 5. See the NIHR Journals Library website for further project information.

Comparison of the Short and Long-Term Outcomes of Endovascular Repair and Open Surgical Repair in the Treatment of Unruptured Abdominal Aortic Aneurysms: Meta-Analysis and Systematic Review

Background

Although the initial results of endovascular repair (EVAR) were promising, a comparison of its long-term efficacy against open surgical repair (OSR) remains largely elusive, and late-onset adverse events have not been systematically evaluated. Since OSR and EVAR are currently the only treatment options available in the management of abdominal aortic aneurysms (AAAs), the main question arising in clinical practice is whether EVAR or OSR confers more favourable short and long-term outcomes for patients presenting with unruptured AAAs.

Aims

The present meta-analysis aims to draw a head-to-head comparison between EVAR and OSR and facilitate the formulation of an evidence-based approach to the clinical management of unruptured AAAs.

Methods

A systematic review was conducted using three databases to identify all relevant studies with comparative data on EVAR vs. OSR. All-cause mortality was the primary outcome. Procedural outcomes, such as stroke, myocardial infarction, renal complications, rupture, and reintervention rates, were determined as secondary outcomes.

Results

Sixteen studies were included for comparative analysis, including four randomised-controlled trials and six non-randomised comparative clinical trials. EVAR conferred a clear perioperative survival advantage as compared to OSR (P < 0.00001). However, this survival advantage did not persist beyond two years post-procedure; all-cause mortality rates were comparable between the two treatment groups at two years (P = 0.09), four years (P = 0.58), and six years (P = 0.88) post-procedure. Although no statistically significant differences in aneurysm-related mortality, postoperative stroke, or myocardial infarction were identified, the OSR group had a statistically significant higher rate of postoperative renal complications. On the other hand, there was a statistically significant higher rate of rupture and reintervention following EVAR.

Conclusion

Whether the initial survival advantage afforded by EVAR is sufficient to justify the long-term risk of rupture, reintervention, and long-term mortality should be determined on a case-by-case basis by the multidisciplinary team overseeing the clinical care of the patient. Currently, it is reasonable to conclude that EVAR is as efficacious as OSR, but it would be invalid to claim it as superior. Ultimately, longer follow-up data must be presented before any definitive conclusions can be established for this potentially revolutionary technique. Presently, one can neither advocate nor refute EVAR over OSR.

The Ethical Dilemma in the Surgical Management of Low Grade Gliomas According to the Variable Availability of Resources and Surgeon Experience

Low grade gliomas (LGGs) affect young individuals in the prime of life. Management may alternatively include biopsy and observation or surgical resection. Recent evidence strongly favors maximal and supramaximal resection of LGGs in optimizing survival metrics. Awake craniotomy with cortical mapping and electrical stimulation along with other preoperative and intraoperative surgical adjuncts, including intraoperative magnetic resonance and diffusion tensor imaging, facilitates maximization of resection and eschews precipitating neurological deficits. Intraoperative imaging permits additional resection of identified residual to be completed within the same surgical session, improving extent of resection and consequently progression free and overall survival. These resources are available in only a few centers throughout the United States, raising an ethical dilemma as to where patients harboring LGGs should most appropriately be treated.

Mortality for Open Abdominal Aortic Aneurysm Repair before and after Endovascular Aortic Repair (EVAR)

The purpose of this study was to determine whether endovascular aortic repair (EVAR) has impacted inhospital mortality for patients undergoing open repair (OR). From 1982 through 2016, 1572 repairs were performed for abdominal aortic aneurysms (AAAs). Both ORs and EVARs were performed by the author at two large, tertiary-care, community-based hospitals. In Period I (1982–1999, n = 863), all AAA repairs were performed open. In Period II (2000–2016; n = 709), repairs were performed both by ORs and EVARs. Demographics were similar between study groups. Mortality for elective repairs in Periods I and II were as follows: I = 1.2 per cent (open, n = 9/756) versus II = 1.7 per cent (open, n = 4/241) versus II = 1.2 per cent (EVAR, n = 5/420). Mortality for patients with ruptured AAAs in Periods I and II were as follows: I = 31.8 per cent (open, n = 34/107) versus II = 32 per cent (open, n = 8/25) versus II = 13 per cent (EVAR, n = 3/23). The results of this study demonstrate that the introduction of EVARs has not negatively impacted the inhospital mortality for elective ORs or emergent AAAs for one vascular surgeon who completed training before EVARs became available.

Impact of Centralisation on Abdominal Aortic Aneurysm Repair Outcomes: Early Experience in Catalonia

OBJECTIVE

Several studies have revealed high volume centres have better outcomes in the treatment of abdominal aortic aneurysms (AAAs), thus supporting centralisation of this procedure into selected centres based on volume. To date however, the real benefit of centralisation of this pathology has not been well demonstrated. The aim of this study was to analyse the impact of centralisation in to high volume centres (defined as those performing more than 30 cases per year) on AAA treatment outcomes carried out in Catalonia (Spain).

METHODS

Data were collected from official national registries (HDMBD) for AAA treated by endovascular aneurysm repair (EVAR) or open repair (OR) over a nine year period. Two time periods were selected for comparison: before centralisation (2009-2014) and after complete centralisation (2015-2017). The primary objective was to determine short term mortality (in hospital and 30 day mortality) and length of stay (LOS) after intact AAA (iAAA) and ruptured AAA (rAAA) repair, before and after centralisation. Uni- and multivariable analyses were performed in order to identify independent outcomes predictors.

RESULTS

A total of 3 501 iAAAs, including 1 124 (32.1%) OR and 2377 (67.9%) EVAR, and 409 rAAAs, including 218 (53.3%) OR and 191 (46.7%) EVAR, were identified. After centralisation, there was a significant decrease in overall mortality in iAAA repair (4.7% vs. 2.0%, p < .001) and rAAA repair (53.1% vs. 41.9%, p = .028). Mortality reduction in iAAAs was significant for OR (8.7% vs. 3.6%, p = .005), but not for EVAR (2.2% vs. 1.5%, p = .25). Overall LOS decreased as well, mainly in iAAAs (9.49 ± 10.84 vs. 7.44 ± 12.23 days, p < .001), and in particular in elective EVAR (7.32 ± 7.73 vs. 6.00 ± 8.97 days, p < .001). Multivariable analysis was identified before the centralisation period as an independent predictor for both mortality (odds ratio 1.484, 95% CI 1.098-2.005, p = .010) and LOS (B coefficient 1.146, 95% CI 0.218-2.073, p = .016).

CONCLUSION

The implementation of a country based centralisation programme for AAA treatment led to a significant reduction in short term mortality, for both iAAA and rAAA, and mainly for elective OR. LOS also significantly decreased, mainly for elective EVAR. These results support the benefit of centralisation of AAA repair procedures.

Association of hospital and surgeon volume with mortality following major surgical procedures: Meta-analysis of meta-analyses of observational studies

Accumulation of the literature has suggested an inverse association between healthcare provider volume and mortality for a wide variety of surgical procedures. This study aimed to perform meta-analysis of meta-analyses (umbrella review) of observational studies and to summarize existing evidence for associations of healthcare provider volume with mortality in major operations.We searched MEDLINE, SCOPUS, and Cochrane Library, and screening of references.Meta-analyses of observational studies examining the association of hospital and surgeon volume with mortality following major operations. The primary outcome is all-cause short-term morality after surgery. Meta-analyses of observational studies of hospital/surgeon volume and mortality were included. Overall level of evidence was classified as convincing (class I), highly suggestive (class II), suggestive (class III), weak (class IV), and non-significant (class V) based on the significance of the random-effects summary odds ratio (OR), number of cases, small-study effects, excess significance bias, prediction intervals, and heterogeneity.Twenty meta-analyses including 4,520,720 patients were included, with 19 types of surgical procedures for hospital volume and 11 types of surgical procedures for surgeon volume. Nominally significant reductions were found in odds ratio in 82% to 84% of surgical procedures in both hospital and surgeon volume-mortality associations. To summarize the overall level of evidence, however, only one surgical procedure (pancreaticoduodenectomy) fulfilled the criteria of class I and II for both hospital and surgeon volume and mortality relationships, with a decrease in OR for hospital (0.42, 95% confidence interval[CI] [0.35-0.51]) and for surgeon (0.38, 95% CI [0.30-0.49]), respectively. In contrast, most of the procedures appeared to be weak or "non-significant."Only a very few surgical procedures such as pancreaticoduodenectomy appeared to have convincing evidence on the inverse surgeon volume-mortality associations, and yet most surgical procedures resulted in having weak or "non-significant" evidence. Therefore, healthcare professionals and policy makers might be required to steer their centralization policy more carefully unless more robust, higher-quality evidence emerges, particularly for procedures considered as having a weak or non-significant evidence level including total knee replacement, thyroidectomy, bariatric surgery, radical cystectomy, and rectal and colorectal cancer resections.

Understanding the impetus for major systems change: A multiple case study of decisions and non-decisions to reconfigure emergency and urgent care services

OBJECTIVE

The optimal organisation of emergency and urgent care services (EUCS) is a perennial problem internationally. Similar to other countries, the Health Service Executive in Ireland pursued EUCS reconfiguration in response to quality and safety concerns, unsustainable costs and workforce issues. However, the implementation of reconfiguration has been inconsistent at a regional level. Our aim was to identify the factors that led to this inconsistency.

METHODS

Using a multiple case study design, six case study regions represented full, partial and little/no reconfiguration at emergency departments (EDs). Data from documents and key stakeholder interviews were analysed using a framework approach with cross-case analysis.

RESULTS

The impetus to reconfigure ED services was triggered by patient safety events, and to a lesser extent by having a region-specific plan and an obvious starting point for changes. However, the complexity of the next steps and political influence impeded reconfiguration in several regions. Implementation was more strategic in regions that reconfigured later, facilitated by clinical leadership and "lead-in time" to plan and sell changes.

CONCLUSION

While the global shift towards centralisation of EUCS is driven by universal challenges, decisions about when, where and how much to implement are influenced by local drivers including context, people and politics. This can contribute to a public perception of inequity and distrust in proposals for major systems change.

Transjugular Intrahepatic Portosystemic Shunt in Patients with Portal Hypertension: Patency Depends on Coverage and Interventionalist's Experience

BACKGROUND AND AIMS

Transjugular intrahepatic portosystemic shunt (TIPS) is the treatment of choice in decompensated portal hypertension. TIPS revision due to thrombosis or stenosis increases morbidity and mortality. Our aim was to investigate patient- and procedure-associated risk factors for TIPS-revision.

PATIENTS AND METHODS

We retrospectively evaluated 189 patients who underwent the TIPS procedure. Only patients who required TIPS revision within 1 year (Group I, 34 patients) and patients who did not require re-intervention within the first year (Group II [control group], 54 patients) were included.

RESULTS

Out of 88 patients, the majority were male (69.3%) and mean age was 56 ± 11 years. Indications for TIPS were refractory ascites (68%), bleeding (24%), and Budd-Chiari syndrome (8%). The most frequent liver disease was alcohol-induced cirrhosis (60%). Forty-three patients (49%) received bare and 45 patients (51%) covered stents, thus resulting in reduction of hepatic venous pressure gradient (HVPG) from 19.0 to 9.0 mm Hg. When comparing patient- and procedure-related factors, the type of stent (p < 0.01) and interventionalist's experience (number of performed TIPS implantations per year; p < 0.05) were the only factors affecting the risk of re-intervention due to stent dysfunction, while age, gender, indication, Child-Pugh, and model of end-stage liver disease score, platelet count, pre- and post-HVPG, additional variceal embolization, stent diameter, and number of stents did not significantly differ.

CONCLUSION

Patients undergoing TIPS procedure should be surveilled closely for shunt dysfunction while covered stents and high-level experience are associated with increased -patency.

National trends in open surgical, endovascular, and branched-fenestrated endovascular aortic aneurysm repair in Medicare patients

BACKGROUND

Open repair effectively prevents rupture for patients with abdominal aortic aneurysm (AAA) and is commonly studied as a metric reflecting hospital and surgeon expertise in cardiovascular care. However, given recent advances in endovascular aneurysm repair (EVAR), such as branched-fenestrated EVAR, it is unknown how commonly open surgical repair is still used in everyday practice.

METHODS

We analyzed trends in open AAA repair, EVAR, and branched-fenestrated EVAR for AAA in Medicare beneficiaries from 2003 to 2013. We used Medicare Part B claims to ascertain counts of these repair types annually during the study period. We assessed regional and national trends in characteristics of the patients and procedure volume.

RESULTS

Between 2003 and 2013, the total number of AAA repairs performed in fee-for-service Medicare patients declined by 26% from 31,582 to 23,421 (P < .001), after a peak number of 32,540 was performed in 2005 (28% decline since 2005). The number of open AAA repairs steadily declined by a total of 76%, from 20,533 in 2003 to 4916 in 2013 (P < .001). Whereas the number of EVARs increased from 11,049 in 2003 to 19,247 in 2011 (P < .001), it has since declined a total of 15% to only 16,362 repairs in 2013 (P < .001). After its introduction in 2011, the number of branched-fenestrated EVAR cases continuously rose from 335 procedures in 2011 to 2143 procedures in 2013 (P < .001). By 2013, virtually all hospital referral regions in the United States had rates of open AAA repair that would have been in the lowest quintile of volume in 2003.

CONCLUSIONS

The number of open AAA repairs fell by nearly 80% during the last decade, whereas traditional EVAR declined slightly and branched-fenestrated EVAR rapidly disseminated into national practice. These results suggest that open AAA repair is now performed too infrequently to be used as a metric in the assessment of hospital and surgeon quality in cardiovascular care. Furthermore, surgical training paradigms will need to reflect the changing dynamics necessary to ensure that surgeons and interventionists can safely perform these high-risk surgical procedures.

[Patient volume and quality in surgery for abdominal aortic aneurysm]

BACKGROUND Patient volume is assumed to affect quality, whereby complex procedures are best performed by those who perform them frequently. We have conducted a systematic review of the research on the association between patient volume and quality of vascular surgery. In this article we describe the outcomes for abdominal aortic aneurysm surgery.MATERIAL AND METHOD We undertook systematic searches in relevant databases. We searched for systematic reviews, and randomised and observational studies. The search was concluded in December 2015. We have summarised the results descriptively and assessed the overall quality of the evidence.RESULTS Forty-six observational studies fulfilled our inclusion criteria. We found a possible association for both hospital and surgeon volume. Higher patient volume may possibly be associated with lower 30-day mortality and lower hospital mortality for both open and endovascular surgery. Although the association appears to apply to both elective and acute hospitalisations, there is greater uncertainty with regard to the most ill patients. For hospital volume there may also be fewer complications for open and endovascular surgery, as well as for all surgery assessed as a whole. We considered the evidence base to be medium to very low quality.INTERPRETATION We found a possible correlation between patient volume and quality indicators such as mortality and complications. It may be advantageous to allocate planned procedures to institutions and surgeons with high volume, while this is less certain with regard to acute hospitalisations.

Adjusted Hospital Outcomes of Abdominal Aortic Aneurysm Surgery Reported in the Dutch Surgical Aneurysm Audit

OBJECTIVE/BACKGROUND

The Dutch Surgical Aneurysm Audit (DSAA) is mandatory for all patients with primary abdominal aortic aneurysms (AAAs) in the Netherlands. The aims are to present the observed outcomes of AAA surgery against the predicted outcomes by means of V-POSSUM (Vascular-Physiological and Operative Severity Score for the enUmeration of Mortality and Morbidity). Adjusted mortality was calculated by the original and re-estimated V(physiology)-POSSUM for hospital comparisons.

METHODS

All patients operated on from January 2013 to December 2014 were included for analysis. Calibration and discrimination of V-POSSUM and V(p)-POSSUM was analysed. Mortality was benchmarked by means of the original V(p)-POSSUM formula and risk-adjusted by the re-estimated V(p)-POSSUM on the DSAA.

RESULTS

In total, 5898 patients were included for analysis: 4579 with elective AAA (EAAA) and 1319 with acute abdominal aortic aneurysm (AAAA), acute symptomatic (SAAA; n = 371) or ruptured (RAAA; n = 948). The percentage of endovascular aneurysm repair (EVAR) varied between hospitals but showed no relation to hospital volume (EAAA: p = .12; AAAA: p = .07). EAAA, SAAA, and RAAA mortality was, respectively, 1.9%, 7.5%, and 28.7%. Elective mortality was 0.9% after EVAR and 5.0% after open surgical repair versus 15.6% and 27.4%, respectively, after AAAA. V-POSSUM overestimated mortality in most EAAA risk groups (p < .01). The discriminative ability of V-POSSUM in EAAA was moderate (C-statistic: .719) and poor for V(p)-POSSUM (C-statistic: .665). V-POSSUM in AAAA repair overestimated in high risk groups, and underestimated in low risk groups (p < .01). The discriminative ability in AAAA of V-POSSUM was moderate (.713) and of V(p)-POSSUM poor (.688). Risk adjustment by the re-estimated V(p)-POSSUM did not have any effect on hospital variation in EAAA but did in AAAA.

CONCLUSION

Mortality in the DSAA was in line with the literature but is not discriminative for hospital comparisons in EAAA. Adjusting for V(p)-POSSUM, revealed no association between hospital volume and treatment or outcome. Risk adjustment for case mix by V(p)-POSSUM in patients with AAAA has been shown to be important.

Reporting individual surgeon outcomes does not lead to risk aversion in abdominal aortic aneurysm surgery

INTRODUCTION Reporting surgeons' outcomes has recently been introduced in the UK. This has the potential to result in surgeons becoming risk averse. The aim of this study was to investigate whether reporting outcomes for abdominal aortic aneurysm (AAA) surgery impacts on the number and risk profile (level of fitness) of patients offered elective treatment. METHODS Publically available National Vascular Registry data were used to compare the number of AAAs treated in those centres across the UK that reported outcomes for the periods 2008-2012, 2009-2013 and 2010-2014. Furthermore, the number and characteristics of patients referred for consideration of elective AAA repair at a single tertiary unit were analysed yearly between 2010 and 2014. Clinic, casualty and theatre event codes were searched to obtain all AAAs treated. The results of cardiopulmonary exercise testing (CPET) were assessed. RESULTS For the 85 centres that reported outcomes in all three five-year periods, the median number of AAAs treated per unit increased between the periods 2008-2012 and 2010-2014 from 192 to 214 per year (p=0.006). In the single centre cohort study, the proportion of patients offered elective AAA repair increased from 74% in 2009-2010 to 81% in 2013-2014, with a maximum of 84% in 2012-2013. The age, aneurysm size and CPET results (anaerobic threshold levels) for those eventually offered elective treatment did not differ significantly between 2010 and 2014. CONCLUSIONS The results do not support the assumption that reporting individual surgeon outcomes is associated with a risk averse strategy regarding patient selection in aneurysm surgery at present.

Relationship between surgeon volume and outcomes: a systematic review of systematic reviews

BACKGROUND

The surgeon volume-outcome relationship has been discussed for many years and its existence or nonexistence is of importance for various reasons. A lot of empirical work has been published on it. We aimed to summarize systematic reviews in order to present current evidence.

METHODS

Medline, Embase, Cochrane database of systematic reviews (CDSR), and health technology assessment websites were searched up to October 2015 for systematic reviews on the surgeon volume-outcome relationship. Reviews were critically appraised, and results were extracted and synthesized by type of surgical procedure/condition.

RESULTS

Thirty-two reviews reporting on 15 surgical procedures/conditions were included. Methodological quality of included systematic reviews assessed with the assessment of multiple systematic reviews (AMSTAR) was generally moderate to high albeit included literature partly neglected considering methodological issues specific to volume-outcome relationship. Most reviews tend to support the presence of a surgeon volume-outcome relationship. This is most clear-cut in colorectal cancer, bariatric surgery, and breast cancer where reviews of high quality show large effects.

CONCLUSIONS

When taking into account its limitations, this overview can serve as an informational basis for decision makers. Our results seem to support a positive volume-outcome relationship for most procedures/conditions. However, forthcoming reviews should pay more attention to methodology specific to volume-outcome relationship. Due to the lack of information, any numerical recommendations for minimum volume thresholds are not possible. Further research is needed for this issue.

Association of hospital structures with mortality from ruptured abdominal aortic aneurysm

BACKGROUND

There is significant variation in the mortality rates of patients with a ruptured abdominal aortic aneurysm (rAAA) admitted to hospital in England. This study sought to investigate whether modifiable differences in hospital structures and processes were associated with differences in patient outcome.

METHODS

Patients diagnosed with rAAA between 2005 and 2010 were extracted from the Hospital Episode Statistics database. After risk adjustment, hospitals were grouped into low-mortality outlier, expected mortality and high-mortality outlier categories. Hospital Trust-level structure and process variables were compared between categories, and tested for an association with risk-adjusted 90-day mortality and non-corrective treatment (palliation) rate using binary logistic regression models.

RESULTS

There were 9877 patients admitted to 153 English NHS Trusts with an rAAA during the study. The overall combined (operative and non-operative) mortality rate was 67·5 per cent (palliation rate 41·6 per cent). Seven hospital Trusts (4·6 per cent) were high-mortality and 15 (9·8 per cent) were low-mortality outliers. Low-mortality outliers used significantly greater mean resources per bed (doctors: 0·922 versus 0·513, P < 0·001; consultant doctors: 0·316 versus 0·168, P < 0·001; nurses: 2·341 versus 1·770, P < 0·001; critical care beds: 0·045 versus 0·019, P < 0·001; operating theatres: 0·027 versus 0·019, P = 0·002) and performed more fluoroscopies (mean 12·6 versus 9·2 per bed; P = 0·046) than high-mortality outlier hospital Trusts. On multivariable analysis, greater numbers of consultants, nurses and fluoroscopies, teaching status, weekday admission and rAAA volume were independent predictors of lower mortality and, excluding rAAA volume, a lower rate of palliation.

CONCLUSION

The variability in rAAA outcome in English National Health Service hospital Trusts is associated with modifiable hospital resources. Such information should be used to inform any proposed quality improvement programme surrounding rAAA.

Can experience improve hospital management?

BACKGROUND

Experience curve effects were first observed in the industrial arena as demonstrations of the relationship between experience and efficiency. These relationships were largely determined by improvements in management efficiency and quality of care. In the health care industry, volume-outcome relationships have been established with respect to quality of care improvement, but little is known about the effects of experience on management efficiency. Here, we examine the relationship between experience and hospital management in Japanese hospitals.

METHODS

The study sample comprised individuals who had undergone surgery for unruptured abdominal aortic aneurysms and had been discharged from participant hospitals between April 1, 2006 and December 31, 2008. We analyzed the association between case volume (both at the hospital and surgeon level) and postoperative complications using multilevel logistic regression analysis. Multilevel log-linear regression analyses were performed to investigate the associations between case volume and length of stay (LOS) before and after surgery.

RESULTS

We analyzed 909 patients and 849 patients using the hospital-level and surgeon-level analytical models, respectively. The odds ratio of postoperative complication occurrence for an increase of one surgery annually was 0.981 (P < 0.001) at the hospital level and 0.982 (P < 0.001) at the surgeon level. The log-linear regression analyses showed that shorter postoperative LOS was significantly associated with high hospital-level case volume (coefficient for an increase of one surgery: -0.006, P = 0.009) and surgeon-level case volume (coefficient for an increase of one surgery: -0.011, P = 0.022). Although an increase of one surgery annually at the hospital level was statistically associated with a reduction of preoperative LOS by 1.1% (P = 0.006), there was no significant association detected between surgeon-level case volume and preoperative LOS (P = 0.504).

CONCLUSION

Experience at the hospital level may contribute to the improvement of hospital management efficiency.

Hospital volume of thoracoabdominal aneurysm repair does not affect mortality in California

OBJECTIVES

Open thoracoabdominal aneurysm repair (TAAR) is a rarely performed but a complicated and morbid procedure. This study compares the morbidity and mortality of open TAAR at high- versus low-volume hospitals.

METHODS

Included patients from California Office of Statewide Health Policy and Development patient discharge database who underwent an open TAAR between 1995 and 2010. High volume was ≥ 9 cases per year. Outcomes included mortality and postoperative complications. Multivariate analyses compared patients at high- versus low-volume hospitals.

RESULTS

A total of 122 hospitals were included, with 5 designated as high volume. Adjusted analysis found no difference in the odds ratio (OR) of mortality or morbidity at high-volume hospitals compared to low-volume hospitals (OR 0.37, P = .077; OR 0.94, P = .834, respectively). However, there was a decreased OR of mortality in high- versus low-volume hospitals when a high-volume hospital was defined as each year after meeting the initial threshold of 9 cases (OR 0.40, P = .040).

CONCLUSION

We found no difference in mortality between low- and high-volume institutions in California, until high-volume hospitals were defined as each year after meeting initial threshold case volume. This may suggest that the benefits of high-volume hospitals on outcomes are maintained after reaching the requisite case volume.

Inter-relationship of procedural mortality rates in vascular surgery in England: retrospective analysis of hospital episode statistics from 2005 to 2010

BACKGROUND

Wide variations in vascular surgical outcomes have been demonstrated in England. The objective of this study was to determine whether risk-adjusted postoperative mortality rates for elective and emergency vascular surgical procedures were inter-related.

METHODS AND RESULTS

A retrospective observational study using National Health Service administrative data on adult patients undergoing elective or emergency vascular surgery from 2005 to 2010. The 10 procedures covered the broad spectrum of workload for a vascular surgical service. The primary outcome measure was in-hospital mortality, and secondary outcomes were 30-day and 1-year mortality. Data were risk-adjusted using multilevel modeling. Analyses comprised a 2-level basket designed to evaluate variations in outcome and whether the outcome of each procedure could be predicted by the composite outcome of all other procedures. A total of 116,596 vascular surgical procedures were performed across 166 providers. For 9 of 10 procedures, there were hospitals lying outside 95% control limits for ≥1 mortality outcome. The key finding was that ≥1 risk-adjusted mortality outcome for any 1 of the 9 vascular surgical procedures could be predicted by the aggregated within provider performance of the other vascular surgical procedures combined.

CONCLUSIONS

Hospital-level risk-adjusted mortality for both elective and emergency vascular procedures in England varies considerably, and providers were globally high or low performers. The data should be made available to patients, relatives, and the purchasers of services to drive improvements in the provision of vascular surgical services.

The incidence and all-cause mortality of pneumonia in patients with schizophrenia: a nine-year follow-up study

OBJECTIVE

This study sought to estimate the incidence, all-cause mortality and relative risks for patients with schizophrenia after a pneumonia diagnosis.

METHODS

The population was identified from the Taiwanese National Health Insurance Research Database (NHIRD) in 1999 and included 59,021 patients with schizophrenia and 236,084 age- and sex-matched control participants without schizophrenia. These participants were randomly selected from the 23,981,020-participant NHIRD, which contain 96% of the entire population. Using the 2000-2008 NIHRD, the incidence and nine-year pneumonia-free survival rate of pneumonia (ICD-9-CM codes 486 and 507.0-507.8) were calculated.

RESULTS

Over nine years, 6055 (10.26%) patients with schizophrenia and 7844 (3.32%) controls had pneumonia. The pneumonia incidence density was 11.4/1000 person-years among the patients with schizophrenia, who experienced a 3.09-fold increased risk of developing pneumonia. After adjusting for other covariates, the patients with schizophrenia still experienced a 1.77-fold increased risk of developing pneumonia. Although, without adjustment, fewer schizophrenia patients than controls died after having pneumonia (2121 [35.12%] vs. 3497 [44.62%]), after adjusting for other variables, the mortality hazard ratio for patients with schizophrenia was 1.39.

CONCLUSIONS

During a nine-year follow-up, the likelihood of developing pneumonia and all-cause mortality among patients with schizophrenia was higher than that of the non-schizophrenia group as was the mortality rate. Interestingly, the psychiatric proportion of days covered (PDC) was positively associated with pneumonia (OR: 2.51) but negatively associated with death (HR: 0.72). These findings imply the importance of iatrogenic factors and psychotropic drugs (including their benefits and side effects) and highlight the directions for future studies.

Towards national surgical surveillance in the UK--a pilot study

OBJECTIVE

The Bristol heart inquiry in the United Kingdom (UK) highlighted the lack of standards for evaluating surgical performance and quality. In 2009, the World Health Organisation (WHO) proposed six standardised metrics for surgical surveillance. This is the first study to collect and analyse such metrics from a cohort of National Health Service (NHS) Trusts in England, helping to determine their feasibility and utility in measuring surgical performance, its impact on public health and mortality, and for tracking surgical trends over time.

METHODS

Freedom of Information Act 2000 (FOI) requests for WHO standardised surgical metrics were made to 36 NHS Trusts in England during July to November 2010. Additional data on Hospital Standardised Mortality Ratio (HSMR), Patient Safety Score and Abdominal Aortic Aneurysm (AAA) volume and mortality was obtained from Dr Foster Health and The Guardian Newspaper. Analysis was performed using mixed-effect logistic regression.

RESULTS

30/36 trusts responded (83%). During 2005-9, 5.4 million operations were performed with a 24.2% increase in annual number of operations. This rising volume within hospitals was associated with lower mortality ratios. A 10% increase in operative volume was associated with a lower day of surgery death rate (DDR OR = 0.94, p = 0.056) and post-operative inpatient 30-day mortality (PDR30 OR = 0.93, p = 0.001). For every 10,000 more operations that an NHS Trust does, a 4% drop in PDR30 mortality was achieved. A 10% increase in the volume of elective AAAs was associated with lower elective AAA (OR = 0.96, p = 0.032) and emergency AAA (OR = 0.95, p = 0.009) PDR30 mortality. Lower DDR mortality was noted for emergency AAA mortality (OR = 0.95, p = 0.025) but not elective AAAs (OR = 0.97, p = 0.116).

CONCLUSION

Standarised surgical metrics can provide policy makers and commissioners with valuable summary data on surgical performance allowing for statistical process control of a complex intervention. This study has shown their collection is feasible albeit using FOI and the first to show a statistically significant volume-outcome relationship for surgery as a whole within hospitals. It adds weight to the argument that patients are safer in larger hospitals or those that become larger by growing their patient base. Together with other measures, such metrics can help build a picture of surgical surveillance in the UK and potentially lead us to safer surgery.

Provider volume and long-term outcome after elective abdominal aortic aneurysm repair

Background

Robust risk-adjusted analyses have demonstrated that a reduction in perioperative mortality is associated with the repair of an abdominal aortic aneurysm (AAA) in centres with a high operative caseload (volume). However, the long-term impact of this volume-related effect on mortality remains unknown.

Methods

Demographic and clinical data were extracted from UK Hospital Episodes Statistics for patients undergoing elective repair of an infrarenal AAA from 1 April 2000 to 31 March 2005. The long-term mortality of this cohort was investigated through linkage to the UK Office for National Statistics (ONS) registry. Risk-adjusted survival was analysed using Cox proportional hazards modelling to identify the effect of hospital volume on long-term mortality.

Results

A total of 14 396 patients with mean age of 72 years, of whom 85·7 per cent were men, underwent elective repair of an infrarenal AAA in England. They were linked to follow-up using ONS data. Risk-adjusted analysis of all-cause mortality by Cox proportional hazards modelling demonstrated a significant effect of hospital volume across all quintiles up to 2 years (P = 0·013). Remodelling the data after excluding in-hospital mortality still demonstrated the significant effect of hospital volume on late outcome.

Conclusion

There is a long-term benefit to patients who undergo elective AAA repair in a high-volume hospital.

Qualitative Impact of the Endovascular Era on Vascular Surgeons’ Comfort Level and Enjoyment With Open and Endovascular AAA Repairs

Objective: To evaluate the qualitative impact of training in the endovascular era (post-2000) on vascular surgeons’ comfort level and enjoyment with abdominal aortic aneurysm (AAA) repairs. Methods: A sample of vascular surgeons (n = 1754) were sent a survey pertaining to their fellowship training and practice of AAA repair. The influence of training- and practice-related variables on qualitative outcomes was assessed. Results: A total of 382 (22%) surgeons completed the survey. Surgeons who performed more endovascular aneurysm repairs (EVARs) than open AAA repairs were more likely to enjoy EVAR ( P < .001). Those completing fellowship after 2000 reported a higher level of procedure-related comfort with EVAR ( P = .001) compared to those completing fellowship before 2000. Conversely, surgeons completing fellowship before 2000 reported a higher level of procedure-related comfort with open AAA repair ( P = .001). Conclusion: The advent of EVAR has changed fellowship training of AAA repair and has translated into changes in both practice patterns and comfort level.

Multicentre study of the quality of a large administrative data set and implications for comparing death rates

Background

The aim was to compare the completeness and accuracy of the English Hospital Episode Statistics (HES) with a ‘gold standard’ data set for a sample of hospitals and to determine the effect of data quality on comparisons of hospital death rates.

Methods

A multicentre audit of data quality was undertaken, based on a sample of all elective abdominal aortic aneurysm (AAA) repairs performed in England. All elective AAA repairs in nine collaborating hospital trusts were included over a 2-year interval. Cases were identified from HES, local databases, hospital administration systems and theatre records. The main outcome measures were the numbers of cases and deaths according to HES compared with case-note review. The recording of co-morbidities and the effect of data accuracy on mortality analyses and risk adjustment were quantified.

Results

A total of 1102 elective AAA repairs were identified from HES data. Of 962 procedures with case-note review, 827 (86·0 per cent, 95 per cent confidence interval 84·0 to 88·0 per cent) were confirmed as elective AAA repair. The survival status with HES was 99·8 per cent accurate on comparison with the Office for National Statistics death registry. There was no significant difference in mortality assessment between the HES data and the ‘gold standard’ data set (5·3 versus 5·0 per cent; P = 0·753). Smaller hospitals were more affected by data inaccuracies than larger hospitals.

Conclusion

This study confirmed that HES data can be used effectively to compare mortality between hospitals. Administrative data will be used increasingly for assessing performance and clinicians should accept responsibility to improve coding. Copyright © 2011 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd.