Association of hospital structures with mortality from ruptured abdominal aortic aneurysm

The effect of edoxaban on apoptosis in an abdominal aortic aneurysm model in rats

Background

This study aimed to evaluate the effects of edoxaban, which is used in venous thrombosis, systemic embolism, and stroke, on an aortic aneurysm model and to demonstrate the pharmacokinetic and molecular effects of edoxaban through the induction of apoptosis.

Methods

In this double-blind experimental study, 21 Wistar albino male rats (mean weight: 290 g; range, 280 to 300 g) were divided into three groups: the sham group (n=7), the abdominal aortic aneurysm (AAA) group (n=7), and the AAA-edoxaban group (n=7). Edoxaban 10 mg/kg was given to the AAA-edoxaban group by oral gavage daily for 30 days. At the end of 30 days, the aneurysmal aorta was surgically removed and histologically examined. The abdominal aorta was surgically exposed and wrapped with a calcium chloride (0.5 mol/L) sponge for 10 min.

Results

Immunohistochemically, aortic sections were marked with caspase-3 and caspase-9 antibodies. It was observed that the pathways that trigger apoptosis (caspase-3 and caspase-9; p <0.004 and p <0.005, respectively) were significantly reduced in the AAA-edoxaban group compared to the AAA group. In the AAA-edoxaban group, it was observed that the expansion in aortic diameter and the deterioration in the elastic fibril structure in the aortic aneurysm were decreased as a result of edoxaban treatment. Edoxaban treatment was observed to reduce cell death in both the tunica intima and tunica media.

Conclusion

This study provided strong evidence of the protective effect of edoxaban on aortic aneurysm-related vascular damage by reducing apoptosis and mitophagy.

[Long-term Results after Endovascular and Open Repair of Ruptured Abdominal Aortic Aneurysm - a Propensity Score Matched Analysis]

BACKGROUND

This retrospective propensity score matched study presents the perioperative mortality and long-term survival up to 9 years after endovascular (EVAR) and open (OAR) repair of patients with ruptured abdominal aortic aneurysm (rAAA) in Germany using health insurance data.

MATERIALS AND METHODS

2170 patients treated between January 1st, 2010 and December 31st, 2016, for rAAA within 24 hours of hospital admission and receiving blood transfusions were enrolled in the study and tracked until December 31st, 2018. For better comparability of EVAR and OAR, a 1:1 propensity score matching with 624 pairs according to patient age, sex and comorbidities was carried out using the R program (Foundation for Statistical Computing, Vienna, Austria).

RESULTS

In the unadjusted groups, 29.1% (631/2170) of the patients were treated with EVAR and 70.9% (1539/2170) with OAR. EVAR patients had a significantly higher overall rate of comorbidities. After adjustment, EVAR patients showed significantly better perioperative survival (EVAR 35.7%, OAR 51.0%, p = 0.000). Perioperative complications occurred in 80.4% of EVAR patients and 80.3% of OAR patients (p = 1.000). At the end of follow-up, Kaplan-Meier estimated that 15.2% of patients survived after EVAR vs. 19.5% after OAR (p = 0.027). In the multivariate Cox regression analysis, OAR, age ≥ 80 years, diabetes mellitus type 2 and renal failure stages 3 to 5 had a negative impact on overall survival. Patients treated on weekdays had a significantly lower perioperative mortality than patients treated during the weekend (perioperative mortality on weekdays 40.6% vs. 53.4% during the weekend; p = 0.000) and a better overall survival as estimated by Kaplan-Meier.

CONCLUSION

Significantly better perioperative and overall survival was observed with EVAR than with OAR in patients with rAAA. The perioperative survival benefit of EVAR was also found in patients older than 80 years. Female gender had no significant influence on perioperative mortality and overall survival. Patients treated on weekends had a significantly poorer perioperative survival than patients treated on weekdays, and this lasted through the end of follow-up. The extent to which this was dependent on hospital structure was unclear.

Next-Generation Sequencing of microRNAs in Small Abdominal Aortic Aneurysms: MiR-24 as a Biomarker

BACKGROUND

Small abdominal aortic aneurysms (AAAs) are asymptomatic but can potentially lead to rupture if left undetected. To date, there is a lack of simple nonradiologic routine tests available for diagnosing AAAs. MicroRNAs (miRNAs) have been proven to be good-quality biomarkers in several diseases, including AAA.

METHODS

An attempt to identify a panel of circulating miRNAs with differential expression in AAAs via next-generation sequencing (NGS) was performed in serum samples: small AAAs (n = 3), large AAAs (n = 3), and controls (n = 3). For miR-24, validation with real-time polymerase chain reaction (PCR) was undertaken in a larger group (n = 80).

RESULTS

In the NGS study, 23 miRNAs were identified as differentially expressed (with statistical significance) in small AAAs in comparison with controls. Among them, miR-24 showed the largest upregulation with 23-fold change (log2FC 4.5, P = 0.024). For large AAAs compared with controls, and small AAAs compared with large AAAs, a panel of 33 and 131 miRNAs showed statistically significant differential expression, respectively. Based on the results of the NGS stage, a literature search was performed, and information regarding AAA pathogenesis, coronary artery disease, and peripheral arterial disease was documented where applicable: miR-24, miR-103, miR-193a, miR-486, miR-582, and miR-3663. Of these 6 miRNAs, miR-24 was chosen for further validation with real-time PCR. Additionally, in the NGS study analysis, 17 miRNAs were common between the small-large AAAs, small AAAs-controls, and large AAAs-controls comparisons: miR-7846, miR-3195, miR-486-2, miR-3194, miR-5589, miR-1538, miR-3178, miR-4771-1, miR-5695, miR-6504, miR-1908, miR-6823, miR-3159, miR-23a, miR-7853, miR-496, and miR-193a. Interestingly, in the validation stage with real-time PCR, miR-24 was found downregulated in small and large AAAs compared with controls (fold-changes: 0.27, P = 0.015 and 0.15, P = 0.005, respectively). No correlation was found between average Ct values, aneurysm diameter, and patients' age.

CONCLUSIONS

Our findings further highlight the importance of miR-24 as a potential biomarker as well as a therapeutic target for abdominal aneurysmal disease. Future research and validation of a panel of miRNAs for AAA would aid in diagnosis and discrimination between diseases with overlapping pathogeneses.

Editor's Choice - Systematic Review and Meta-Analysis of the Impact of Institutional and Surgeon Procedure Volume on Outcomes After Ruptured Abdominal Aortic Aneurysm Repair

OBJECTIVE

To investigate whether there is a correlation between institutional or surgeon case volume and outcomes in patients with ruptured abdominal aortic aneurysm (rAAA).

DATA SOURCES

The Healthcare Database Advanced Search interface developed by the National Institute of Health and Care Excellence was used to search MEDLINE, Embase, CINAHL, and CENTRAL.

REVIEW METHODS

The systematic review complied with the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines with the protocol registered in PROSPERO (CRD42020213121). Prognostic studies were considered comparing outcomes of patients with rAAA undergoing repair in high and low volume institutions or by high and low volume surgeons. Pooled estimates for peri-operative mortality were calculated using the odds ratio (OR) and 95% confidence intervals (CI), applying the Mantel-Haenszel method. Analysis of adjusted outcome estimates was performed with the generic inverse variance method.

RESULTS

Thirteen studies reporting a total of 120 116 patients were included. Patients treated in low volume centres had a statistically significantly higher peri-operative mortality than those treated in high volume centres (OR 1.39; 95% CI 1.22 - 1.59). Subgroup analysis showed a mortality difference in favour of high volume centres for both endovascular aneurysm repair (EVAR; OR 1.61, 95% CI 1.11 - 2.35) and open repair (OR 1.50, 95% CI 1.25 - 1.81). Adjusted analysis showed a benefit of treatment in high volume centres for open repair (OR 1.68, 95% CI 1.21 - 2.33) but not for EVAR (OR 1.42, 95% CI 0.84 - 2.41). Differences in peri-operative mortality between low and high volume surgeons were not statistically significant for either EVAR (OR 1.06, 95% CI 0.59 - 1.89) or open surgical repair (OR 1.18, 95% CI 0.87 - 1.63).

CONCLUSION

A high institutional volume may result in a reduction of peri-operative mortality following surgery for rAAA. This peri-operative survival advantage is more pronounced for open surgery than EVAR. Individual surgeon caseload was not found to have a significant impact on outcomes.

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.

Editor's Choice - Systematic Review and Meta-Analysis of the Effect of Weekend Admission on Outcomes for Ruptured Abdominal Aortic Aneurysms: A Call for an Equitable Seven Day Vascular Service

OBJECTIVE

"The weekend effect" of higher patient mortality when presenting at a weekend compared with a weekday has been established for several conditions. The aim of this study was to investigate whether a weekend effect exists for the emergency condition of ruptured abdominal aortic aneurysm.

DATA SOURCES

A review of the literature was conducted in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines (PROSPERO registration number CRD42020157484). MEDLINE, EMBASE and CINAHL were searched using the Healthcare Databases Advanced Search interface developed by NICE.

REVIEW METHODS

The prognostic factor of interest was weekend admission. The primary outcome of interest was all cause peri-operative mortality, with a secondary outcome of hospital length of stay. A random effects meta-analysis was performed, and the results were reported as summary odds ratio (OR) and 95% confidence interval (CI).

RESULTS

Twelve observational cohort studies published between 2001 and 2019 comprising 14 patient cohorts with a total of 95 856 patients were eligible for quantitative synthesis. Patients presenting on a weekend had a significantly higher risk of unadjusted in hospital mortality (OR 1.20, 95% CI 1.10 - 1.31, p < .001). Both the unadjusted 30 day mortality risk (OR 1.16, 95% CI 0.98 - 1.39, p = .090) and unadjusted 90 day mortality risk (OR 1.12, 95% CI 0.90 - 1.40, p = .30) were higher for those presenting at a weekend, but neither reached statistical significance. There was a significantly greater risk of combined unadjusted in hospital, 30 and 90 day mortality for those presenting at a weekend (OR 1.17, 95% CI 1.09 - 1.27, p < .001). Hospital length of stay was not statistically different between groups.

CONCLUSION

There is an association between weekend admission and higher mortality in patients presenting with ruptured abdominal aortic aneurysm.

"Turn downs" in aortic emergencies: Reassurance or uncertainty?

"Turn-down" rate has been reported to have a significant influence on outcomes, and being turned down for an operation is associated with significant short-term mortality risk. A study examining the impact of the pandemic on the "turn-down" rates of acute aortic syndromes in the United Kingdom reported an overall "turn-down" rate of  7.3% in the early part of the pandemic. This review examines the significance of "turn-downs" in this setting and scrutinizes the adequacy of reporting this complex variable.

The Safer Nursing Care Tool as a guide to nurse staffing requirements on hospital wards: observational and modelling study

Background

The Safer Nursing Care Tool is a system designed to guide decisions about nurse staffing requirements on hospital wards, in particular the number of nurses to employ (establishment). The Safer Nursing Care Tool is widely used in English hospitals but there is a lack of evidence about how effective and cost-effective nurse staffing tools are at providing the staffing levels needed for safe and quality patient care.

Objectives

To determine whether or not the Safer Nursing Care Tool corresponds to professional judgement, to assess a range of options for using the Safer Nursing Care Tool and to model the costs and consequences of various ward staffing policies based on Safer Nursing Care Tool acuity/dependency measure.

Design

This was an observational study on medical/surgical wards in four NHS hospital trusts using regression, computer simulations and economic modelling. We compared the effects and costs of a ‘high’ establishment (set to meet demand on 90% of days), the ‘standard’ (mean-based) establishment and a ‘flexible (low)’ establishment (80% of the mean) providing a core staff group that would be sufficient on days of low demand, with flexible staff re-deployed/hired to meet fluctuations in demand.

Setting

Medical/surgical wards in four NHS hospital trusts.

Main outcome measures

The main outcome measures were professional judgement of staffing adequacy and reports of omissions in care, shifts staffed more than 15% below the measured requirement, cost per patient-day and cost per life saved.

Data sources

The data sources were hospital administrative systems, staff reports and national reference costs.

Results

In total, 81 wards participated (85% response rate), with data linking Safer Nursing Care Tool ratings and staffing levels for 26,362 wards × days (96% response rate). According to Safer Nursing Care Tool measures, 26% of all ward-days were understaffed by ≥ 15%. Nurses reported that they had enough staff to provide quality care on 78% of shifts. When using the Safer Nursing Care Tool to set establishments, on average 60 days of observation would be needed for a 95% confidence interval spanning 1 whole-time equivalent either side of the mean. Staffing levels below the daily requirement estimated using the Safer Nursing Care Tool were associated with lower odds of nurses reporting ‘enough staff for quality’ and more reports of missed nursing care. However, the relationship was effectively linear, with staffing above the recommended level associated with further improvements. In simulation experiments, ‘flexible (low)’ establishments led to high rates of understaffing and adverse outcomes, even when temporary staff were readily available. Cost savings were small when high temporary staff availability was assumed. ‘High’ establishments were associated with substantial reductions in understaffing and improved outcomes but higher costs, although, under most assumptions, the cost per life saved was considerably less than £30,000.

Limitations

This was an observational study. Outcomes of staffing establishments are simulated.

Conclusions

Understanding the effect on wards of variability of workload is important when planning staffing levels. The Safer Nursing Care Tool correlates with professional judgement but does not identify optimal staffing levels. Employing more permanent staff than recommended by the Safer Nursing Care Tool guidelines, meeting demand most days, could be cost-effective. Apparent cost savings from ‘flexible (low)’ establishments are achieved largely by below-adequate staffing. Cost savings are eroded under the conditions of high temporary staff availability that are required to make such policies function.

Future work

Research is needed to identify cut-off points for required staffing. Prospective studies measuring patient outcomes and comparing the results of different systems are feasible.

Trial registration

Current Controlled Trials ISRCTN12307968.

Funding

This project was funded by the National Institute for Health Research (NIHR) Health Services and Delivery Research programme and will be published in full inHealth Services and Delivery Research; Vol. 8, No. 16. See the NIHR Journals Library website for further project information.

Outcomes of aortic aneurysm surgery in England: a nationwide cohort study using hospital admissions data from 2002 to 2015

Background

The United Kingdom aortic aneurysms (AA) services have undergone reconfiguration to improve outcomes. The National Health Service collects data on all hospital admissions in England. The complex administrative datasets generated have the potential to be used to monitor activity and outcomes, however, there are challenges in using these data as they are primarily collected for administrative purposes. The aim of this study was to develop standardised algorithms with the support of a clinical consensus group to identify all AA activity, classify the AA management into clinically meaningful case mix groups and define outcome measures that could be used to compare outcomes among AA service providers.

Methods

In-patient data about aortic aneurysm (AA) admissions from the 2002/03 to 2014/15 were acquired. A stepwise approach, with input from a clinical consensus group, was used to identify relevant cases. The data is primarily coded into episodes, these were amalgamated to identify admissions; admissions were linked to understand patient pathways and index admissions. Cases were then divided into case-mix groups based upon examination of individually sampled and aggregate data. Consistent measures of outcome were developed, including length of stay, complications within the index admission, post-operative mortality and re-admission.

Results

Several issues were identified in the dataset including potential conflict in identifying emergency and elective cases and potential confusion if an inappropriate admission definition is used. Ninety six thousand seven hundred thirty-five patients were identified using the algorithms developed in this study to extract AA cases from Hospital episode statistics. From 2002 to 2015, 83,968 patients (87% of all cases identified) underwent repair for AA and 12,767 patients (13% of all cases identified) died in hospital without any AA repair. Six thousand three hundred twenty-nine patients (7.5%) had repair for complex AA and 77,639 (92.5%) had repair for infra-renal AA.

Conclusion

The proposed methods define homogeneous clinical groups and outcomes by combining administrative codes in the data. These methodologically robust methods can help examine outcomes associated with previous and current service provisions and aid future reconfiguration of aortic aneurysm surgery services.

Evaluating the impact of organisational digital maturity on clinical outcomes in secondary care in England

All healthcare systems are increasingly reliant on health information technology to support the delivery of high-quality, efficient and safe care. Data on its effectiveness are however limited. We therefore sought to examine the impact of organisational digital maturity on clinical outcomes in secondary care within the English National Health Service. We conducted a retrospective analysis of routinely collected administrative data for 13,105,996 admissions across 136 hospitals in England from 2015 to 2016. Data from the 2016 NHS Clinical Digital Maturity Index were used to characterise organisational digital maturity. A multivariable regression model including 12 institutional covariates was utilised to examine the relationship between one measure of organisational digital maturity and five key clinical outcome measures. There was no significant relationship between organisational digital maturity and risk-adjusted 30-day mortality, 28-day readmission rates or complications of care. In multivariable analysis risk-adjusted long length of stay and harm-free care were significantly related to aspects of organisational digital maturity; digitally mature hospitals may not only deliver more harm-free care episodes but also may have a significantly increased risk of patients experiencing a long length of stay. Organisational digital maturity is to some extent related to selected clinical outcomes in secondary care in England. Digital maturity is, however, also strongly linked to other institutional factors that likely play a greater role in influencing clinical outcomes. There is a need to better understand how health IT impacts care delivery and supports other drivers of hospital quality.

The weekend effect: does hospital mortality differ by day of the week? A systematic review and meta-analysis

BACKGROUND

The concept of a weekend effect, poorer outcomes for patients admitted to hospitals at the weekend is not new, but is the focus of debate in England. Many studies have been published which consider outcomes for patients on admitted at the weekend. This systematic review and meta-analysis aims to estimate the effect of weekend admission on mortality in UK hospitals.

METHODS

This is a systematic review and meta-analysis of published studies on the weekend effect in UK hospitals. We used EMBASE, MEDLINE, HMIC, Cochrane, Web of Science and Scopus to search for relevant papers. We included systematic reviews, randomised controlled trials and observational studies) on patients admitted to hospital in the UK and published after 2001. Our outcome was death; studies reporting mortality were included. Reviewers identified studies, extracted data and assessed the quality of the evidence, independently and in duplicate. Discrepancy in assessment was considered by a third reviewer. All meta-analyses were performed using a random-effects meta-regression to incorporate the heterogeneity into the weighting.

RESULTS

Forty five articles were included in the qualitative synthesis. 53% of the articles concluded that outcomes for patients either undergoing surgery or admitted at the weekend were worse. We included 39 in the meta-analysis which contributed 50 separate analyses. We found an overall effect of 1.07 [odds ratio (OR)] (95%CI:1.03-1.12), suggesting that patients admitted at the weekend had higher odds of mortality than those admitted during the week. Sub-group analyses suggest that the weekend effect remained when measures of case mix severity were included in the models (OR:1.06 95%CI:1.02-1.10), but that the weekend effect was not significant when clinical registry data was used (OR:1.03 95%CI: 0.98-1.09). Heterogeneity was high, which may affect generalisability.

CONCLUSIONS

Despite high levels of heterogeneity, we found evidence of a weekend effect in the UK, even after accounting for severity of disease. Further work is required to examine other potential explanations for the "weekend effect" such as staffing levels and other organisational factors.

TRIAL REGISTRATION

PROSPERO International Prospective Register of Systematic Reviews -registration number: CRD42016041225 .

Abdominal aortic aneurysms

An abdominal aortic aneurysm (AAA) is a localized dilatation of the infrarenal aorta. AAA is a multifactorial disease, and genetic and environmental factors play a part; smoking, male sex and a positive family history are the most important risk factors, and AAA is most common in men >65 years of age. AAA results from changes in the aortic wall structure, including thinning of the media and adventitia due to the loss of vascular smooth muscle cells and degradation of the extracellular matrix. If the mechanical stress of the blood pressure acting on the wall exceeds the wall strength, the AAA ruptures, causing life-threatening intra-abdominal haemorrhage - the mortality for patients with ruptured AAA is 65-85%. Although AAAs of any size can rupture, the risk of rupture increases with diameter. Intact AAAs are typically asymptomatic, and in settings where screening programmes with ultrasonography are not implemented, most cases are diagnosed incidentally. Modern functional imaging techniques (PET, CT and MRI) may help to assess rupture risk. Elective repair of AAA with open surgery or endovascular aortic repair (EVAR) should be considered to prevent AAA rupture, although the morbidity and mortality associated with both techniques remain non-negligible.

Characteristics, Stratification and Time to Death in a Population-Based Cohort of Patients with Ruptured Abdominal Aortic Aneurysms Not Undergoing Surgery

BACKGROUND

The available literature on ruptured abdominal aortic aneurysms (rAAA) centers on survival after operation and commonly, reasons why some patients do not undergo surgery are not addressed. The aim of the present study is to examine, in a population-based cohort, the characteristics, stratification and time to death of patients admitted to hospital, but not undergoing operation for rAAA.

METHODS

A retrospective, single-center study. All patients admitted to Stavanger University Hospital from the primary catchment area with rAAA on admission or in-hospital from 2000 to 2014 were included.

RESULTS

Altogether 214 patients with rAAA were identified; 57 (27%) patients did not undergo surgery. The proportion of women was significantly higher (37 vs. 14%; p < .001) in patients not having surgery. The reasons for not undergoing operation were patient 'not fit for surgery' (30%), 'dying or agonal' at time of diagnosis (26%), 'did not want operation' (21%) and 'diagnosed at autopsy' (23%). Of the non-operated patients, 45 had rAAA on arrival to hospital, 12 had in-hospital rupture and 21 patients had previously been diagnosed with an abdominal aortic aneurysm. Non-operative treatment was uniformly fatal. The 45 patients with rAAA on arrival were scored using four scoring systems, the predicted mortality varied widely, and the median time from admission to death was 7.4 h (range 0-1337).

CONCLUSION

In about half of patients, a decision not to operate was made by the consultant vascular surgeon or the patient. In the subgroup of patients not diagnosed until autopsy or having an in-hospital rupture, an earlier diagnosis might have altered the outcome.

A Majority of Admitted Patients With Ruptured Abdominal Aortic Aneurysm Undergo and Survive Corrective Treatment: A Population-Based Retrospective Cohort Study

Background

Abdominal aortic aneurysm (AAA) is an asymptomatic, potentially lethal condition predominantly found in elderly. The mortality is 100 % if rupture occurs and left untreated, but even in treated patients the mortality is substantial. Female sex and treatment with open repair rather than endovascular aortic repair (EVAR) have been reported to negatively affect outcome. The objective was to describe the contemporary care and outcome of all treated and untreated patients with ruptured AAA (rAAA) admitted to hospital.

Method

Population-based retrospective investigation, including all patients admitted to the emergency departments within Stockholm County diagnosed with rAAA 2009–2013. All identified patients’ charts (n = 297) were analyzed; the study cohort includes 283 verified patients.

Results

Men were in majority [214 (76 %), 69 (24 %) women] and were younger than women (78 vs 82 years, p < 0.001). A majority of patients were treated (212/283, 75 %), a similar proportion of women and men. Untreated patients had a higher mean age (84 vs 77 years, p < 0.001). The proportion treated with EVAR was 27 %, and they were older than OR treated (79 vs 76 years, p = 0.043). Forty-seven percentage of patients admitted with rAAA survived 30 days, and 62 % of treated patients survived 30 days. The 30-day mortality for women and men was similar.

Conclusions

Our results and other contemporary series show a shift toward a higher rate of treated patients with rAAA, and improving outcomes, similar for women and men. The increased use of EVAR contributes to this improvement in short-term outcome. High age influences the willingness to treat patients with rAAA.

Resource variation in colorectal surgery: a national centre level analysis

AIM

Delivery of quality colorectal surgery requires adequate resources. We set out to assess the relationship between resources and outcomes in English colorectal units.

METHOD

Data were extracted from the Association of Coloproctology of Great Britain and Ireland resource questionnaire to profile resources. This was correlated with Hospital Episode Statistics outcome data including 90-day mortality and readmissions. Patient satisfaction measures were extracted from the Cancer Experience Patient Survey and compared at unit level. Centres were divided by workload into low, middle and top tertile.

RESULTS

Completed questionnaires were received from 75 centres in England. Service resources were similar between low and top tertiles in access to Confidential Enquiry into Patient Outcome and Death (CEPOD) theatre, level two or three beds per 250 000 population or the likelihood of having a dedicated colorectal ward. There was no difference in staffing levels per 250 000 unit of population. Each 10% increase in the proportion of cases attempted laparoscopically was associated with reduced 90-day unplanned readmission (relative risk 0.94, 95% CI 0.91-0.97, P < 0.001). The presence of a dedicated colorectal ward (relative risk 0.85, 95% CI 0.73-0.99, P = 0.040) was also associated with a significant reduction in unplanned readmissions. There was no association between staffing or service factors and patient satisfaction.

CONCLUSION

Resource levels do not vary based on unit of population. There is benefit associated with increased use of laparoscopy and a dedicated surgical ward. Alternative measures to assess the relationship between resources and outcome, such as failure to rescue, should be explored in UK practice.

Ruptured abdominal aortic aneurysm: Is endovascular aneurysm repair the answer for everybody?

Treatment paradigms for elective repair of asymptomatic abdominal aortic aneurysms (AAA) have evolved during the past 2 decades, with endovascular aneurysm repair as the preferred treatment modality. The patient care strategy for emergent treatment for ruptured AAA is not as straightforward, due in part to surgeon expertise and stent-graft availability at the institution. Although most reports have extrapolated elective endovascular aneurysm repair feasibility data to the ruptured AAA patient and the aneurysm anatomy, these expectations should be interpreted with caution. In the absence of level I evidence, and lack of adequate local hospital resources, endovascular aneurysm repair-first policy might not be feasible for all the patients who present with ruptured AAA.

Ambulance smartphone tool for field triage of ruptured aortic aneurysms (FILTR): study protocol for a prospective observational validation of diagnostic accuracy

INTRODUCTION

Rupture of an abdominal aortic aneurysm (rAAA) carries a considerable mortality rate and is often fatal. rAAA can be treated through open or endovascular surgical intervention and it is possible that more rapid access to definitive intervention might be a key aspect of improving mortality for rAAA. Diagnosis is not always straightforward with up to 42% of rAAA initially misdiagnosed, introducing potentially harmful delay. There is a need for an effective clinical decision support tool for accurate prehospital diagnosis and triage to enable transfer to an appropriate centre.

METHODS AND ANALYSIS

Prospective multicentre observational study assessing the diagnostic accuracy of a prehospital smartphone triage tool for detection of rAAA. The study will be conducted across London in conjunction with London Ambulance Service (LAS). A logistic score predicting the risk of rAAA by assessing ten key parameters was developed and retrospectively validated through logistic regression analysis of ambulance records and Hospital Episode Statistics data for 2200 patients from 2005 to 2010. The triage tool is integrated into a secure mobile app for major smartphone platforms. Key parameters collected from the app will be retrospectively matched with final hospital discharge diagnosis for each patient encounter. The primary outcome is to assess the sensitivity, specificity and positive predictive value of the rAAA triage tool logistic score in prospective use as a mob app for prehospital ambulance clinicians. Data collection started in November 2014 and the study will recruit a minimum of 1150 non-consecutive patients over a time period of 2 years.

ETHICS AND DISSEMINATION

Full ethical approval has been gained for this study. The results of this study will be disseminated in peer-reviewed publications, and international/national presentations.

TRIAL REGISTRATION NUMBER

CPMS 16459; pre-results.

High proportion of known abdominal aortic aneurysm in patients with rupture indicates surveillance deficiency

OBJECTIVE

This study assessed the proportion of previously known abdominal aortic aneurysm (AAA) in patients presenting with a ruptured AAA (rAAA) and analyzed the reasons for nontreatment at the time of the initial AAA diagnosis.

METHODS

This retrospective, observational study included all patients with rAAA admitted to a hospital in the counties of Stockholm and Gotland during 2009 to 2013. The patients' records were retrospectively reviewed, with extraction of data on previously detected AAA, demographics, and mortality at 30 and 90 days.

RESULTS

We identified 283 patients (76% men) with a mean age of 78.7 years. An AAA had been previously detected in 85 (30%). The overall mortality was higher (68% vs 53%; P = .018) and the intervention rate was lower in patients with a previously detected AAA (59% vs 82%, P < .001). The 90-day mortality rate for all treated rAAA was 43%. Reasons for nontreatment at the initial AAA detection were denial of elective surgery in 31 (36%), patient choice in 15 (18%), size-related in 11 (13%), and surveillance deficiency in 26 (31%). The latter group included patients who failed to comply, missed referral for computed tomography scans, and lack of follow-up of radiology reports. At the time of rupture, 22 patients (85%) were treated, with 30-day and 90-day mortality rates both at 41% (n = 9).

CONCLUSIONS

One-third of patients admitted with a rAAA had a previously detected AAA. The surgeons' decision to deny elective surgery and surveillance deficiency were the two main reasons for nontreatment at time of the AAA diagnosis. Improved patient-specific protocols to reduce the surveillance gaps and new methods of determining rupture risk in each case of AAA could be two possible future strategies to reduce the incidence of rupture.

Consultant outcomes publication and surgical training: Consensus recommendations by the association of surgeons in training

Consultant Outcomes Publication (COP) has the longest history in cardiothoracic surgery, where it was introduced in 2005. Subsequently COP has been broadened to include all surgical specialties in NHS England in 2013-14. The Association of Surgeons in Training (ASiT) fully supports efforts to improve patient care and trust in the profession and is keen to overcome potential unintended adverse effects of COP. Identification of these adverse effects is the first step in this process: Firstly, there is a risk that COP may lead to reluctance by consultants to provide trainees with the necessary appropriate primary operator experience to become skilled consultant surgeons for the future. Secondly, COP may lead to inappropriately cautious case selection. This adjusted case mix affects both patients who are denied operations, and also limits the complexity of the case mix to which surgical trainees are exposed. Thirdly, COP undermines efforts to train surgical trainees in non-technical skills and human factors, simply obliterating the critical role of the multidisciplinary team and organisational processes in determining outcomes. This tunnel vision masks opportunities to improve patient care and outcomes at a unit level. It also misinforms the public as to the root causes of adverse events by failing to identify care process deficiencies. Finally, for safe surgical care, graduate retention and morale is important - COP may lead to high calibre trainees opting out of surgical careers, or opting to work abroad. The negative effects of COP on surgical training and trainees must be addressed as high quality surgical training and retention of high calibre graduates is essential for excellent patient care.

Mortality of emergency general surgical patients and associations with hospital structures and processes

BACKGROUND

Variations in patient outcomes between providers have been described for emergency admissions, including general surgery. The aim of this study was to investigate whether differences in modifiable hospital structures and processes were associated with variance in mortality, amongst patients admitted for emergency colorectal laparotomy, peptic ulcer surgery, appendicectomy, hernia repair and pancreatitis.

METHODS

Adult emergency admissions in the English NHS were extracted from the Hospital Episode Statistics between April 2005 and March 2010. The association between mortality and structure and process measures including medical and nursing staffing levels, critical care and operating theatre availability, radiology utilization, teaching hospital status and weekend admissions were investigated.

RESULTS

There were 294 602 emergency admissions to 156 NHS Trusts (hospital systems) with a 30-day mortality of 4.2%. Trust-level mortality rates for this cohort ranged from 1.6 to 8.0%. The lowest mortality rates were observed in Trusts with higher levels of medical and nursing staffing, and a greater number of operating theatres and critical care beds relative to provider size. Higher mortality rates were seen in patients admitted to hospital at weekends [OR 1.11 (95% CI 1.06-1.17) P<0.0001], in Trusts with fewer general surgical doctors [1.07 (1.01-1.13) P=0.019] and with lower nursing staff ratios [1.07 (1.01-1.13) P=0.024].

CONCLUSIONS

Significant differences between Trusts were identified in staffing and other infrastructure resources for patients admitted with an emergency general surgical diagnosis. Associations between these factors and mortality rates suggest that potentially modifiable factors exist that relate to patient outcomes, and warrant further investigation.

Comparison of long-term mortality after ruptured abdominal aortic aneurysm in England and Sweden

BACKGROUND

Concern has been raised regarding international discrepancies in perioperative mortality after repair of ruptured abdominal aortic aneurysm (rAAA). The variation in in-hospital mortality is difficult to interpret, owing to international differences in discharge strategies. This study compared 90-day and 5-year mortality in patients who had a rAAA in England and Sweden.

METHODS

Patients undergoing rAAA repair were identified from English Hospital Episode Statistics and the Swedish Vascular Registry (Swedvasc) between 2003 and 2012. Ninety-day and 5-year mortality were compared after matching for age and sex. Within-country analyses examined the impact of co-morbidity, teaching hospital status or hospital annual caseload, adjusted with causal inference techniques.

RESULTS

Some 12 467 patients underwent rAAA repair in England, of whom 83.2 per cent were men; the median (i.q.r.) age was 75 (70-80) years. A total of 2829 Swedish patients underwent rAAA repair, of whom 81.3 per cent were men; their median (i.q.r.) age was 75 (69-80) years. The 90-day mortality rate was worse in England (44.0 per cent versus 33.4 per cent in Sweden; P < 0.001), as was 5-year mortality (freedom from mortality 38.6 versus 46.3 per cent respectively; P < 0.001). In England, lower mortality was seen in teaching hospitals with larger bed capacity, higher annual caseloads and greater use of endovascular aneurysm repair (EVAR). In Sweden, lower mortality was associated with EVAR, high annual caseload, or surgery on weekdays compared with weekends.

CONCLUSION

Short- and long-term mortality after rAAA repair was higher in England. In both countries, mortality was lowest in centres performing greater numbers of AAA repairs per annum, and more EVAR procedures.