Protocol for an independent patient data meta-analysis of prophylactic mesh placement for incisional hernia prevention after abdominal aortic aneurysm surgery: a collaborative European Hernia Society project (I-PREVENT-AAA).

INTRODUCTION: Incisional hernia (IH) is a prevalent and potentially dangerous complication of abdominal surgery, especially in high-risk groups. Mesh reinforcement of the abdominal wall has been studied as a potential intervention to prevent IHs. Randomised controlled trials (RCTs) have demonstrated that prophylactic mesh reinforcement after abdominal surgery, in general, is effective and safe. In patients with abdominal aortic aneurysm (AAA), prophylactic mesh reinforcement after open repair has not yet been recommended in official guidelines, because of relatively small sample sizes in individual trials. Furthermore, the identification of subgroups that benefit most from prophylactic mesh placement requires larger patient numbers. Our primary aim is to evaluate the efficacy and effectiveness of the use of a prophylactic mesh after open AAA surgery to prevent IH by performing an individual patient data meta-analysis (IPDMA). Secondary aims include the evaluation of postoperative complications, pain and quality of life, and the identification of potential subgroups that benefit most from prophylactic mesh reinforcement. METHODS AND ANALYSIS: We will conduct a systematic review to identify RCTs that study prophylactic mesh placement after open AAA surgery. Cochrane Central Register of Controlled Trials, MEDLINE Ovid, Embase, Web of Science Core Collection and Google Scholar will be searched from the date of inception onwards. RCTs must directly compare primary sutured closure with mesh closure in adult patients who undergo open AAA surgery. Lead authors of eligible studies will be asked to share individual participant data (IPD). The risk of bias (ROB) for each included study will be assessed using the Cochrane ROB tool. An IPDMA will be performed to evaluate the efficacy, with the IH rate as the primary outcome. Any signs of heterogeneity will be evaluated by Forest plots. Time-to-event analyses are performed using Cox regression analysis to evaluate risk factors. ETHICS AND DISSEMINATION: No new data will be collected in this study. We will adhere to institutional, national and international regulations regarding the secure and confidential sharing of IPD, addressing ethics as indicated. We will disseminate findings via international conferences, open-source publications in peer-reviewed journals and summaries posted online. PROSPERO REGISTRATION NUMBER: CRD42022347881.

Quality assurance for the NHS abdominal aortic aneurysm screening programme in England.

INTRODUCTION: The National Health Service Abdominal Aortic Aneurysm Screening Programme (NAAASP) was introduced in England in 2009 to offer ultrasound screening to men over 65 years, in order to reduce aneurysm-related deaths. This study describes the development of a quality assurance (QA) process and conducts an analysis of the first round of QA visit reports. The aim was to identify themes where local providers can target their efforts for improvement. METHODS: Forty-one providers were assessed over 4 years using a process of QA visits adapted from previously established screening programmes. A mixture of qualitative and quantitative methods was used to analyse the 41 QA reports, which identified a range of recommendations for providers. The data were coded for key words and assigned to themes. The number of recommendations per visit report was compared with experience of the providers and performance against national screening standards. RESULTS: A total of 773 recommendations were made, with an average of 19 per QA visit. Around one third of the recommendations were based on governance and leadership standards, with 43.0 per cent of those based around commissioning and accountability. A significant relationship was seen between number of infrastructure recommendations and performance against standards. CONCLUSION: This review of a QA cycle found that sound infrastructure is key to the success of a local provider.

Editor's Choice - Update of the European Society for Vascular Surgery (ESVS) 2020 Clinical Practice Guidelines on the Management of Acute Limb Ischaemia in Light of the COVID-19 Pandemic, Based on a Scoping Review of the Literature.

OBJECTIVE: To perform a scoping review of how patients with COVID-19 are affected by acute limb ischaemia (ALI) and evaluate the recommendations of the 2020 ESVS ALI Guidelines for these patients. METHODS: Research questions were defined, and a systematic literature search was performed following the PRISMA guidelines. Abstracts and unpublished literature were not included. The definition of ALI in this review is in accordance with the ESVS guidelines. RESULTS: Most identified papers were case reports or case series, although population based data and data from randomised controlled trials were also identified. In total, 114 unique and relevant papers were retrieved. Data were conflicting concerning whether the incidence of ALI increased, or remained unchanged, during the pandemic. Case reports and series reported ALI in patients who were younger and healthier than usual, with a greater proportion affecting the upper limb. Whether or not this is coincidental remains uncertain. The proportion of men/women affected seems unchanged. Most reported cases were in hospitalised patients with severe COVID-19. Patients with ALI as their first manifestation of COVID-19 were reported. Patients with ALI have a worse outcome if they have a simultaneous COVID-19 infection. High levels of D-dimer may predict the occurrence of arterial thromboembolic events in patients with COVID-19. Heparin resistance was observed. Anticoagulation should be given to hospitalised COVID-19 patients in prophylactic dosage. Most of the treatment recommendations from the ESVS Guidelines remained relevant, but the following were modified regarding patients with COVID-19 and ALI: 1) CTA imaging before revascularisation should include the entire aorta and iliac arteries; 2) there should be a high index of suspicion, early testing for COVID-19 infection and protective measures are advised; and 3) there should be preferential use of local or locoregional anaesthesia during revascularisation. CONCLUSION: Although the epidemiology of ALI has changed during the pandemic, the recommendations of the ESVS ALI Guidelines remain valid. The above mentioned minor modifications should be considered in patients with COVID-19 and ALI.

Outcomes in Men From the NHS Abdominal Aortic Aneurysm Screening Programme With a Large Aneurysm Referred for Intervention.

OBJECTIVE: The NHS Abdominal Aortic Aneurysm Screening Programme (NAAASP) has been implemented since 2013. Men with a large aneurysm >54 mm, either at first screen or during surveillance, are referred for intervention. The aim of the present study was to explore outcomes in these men and to see whether there was any regional variation in treatment rates and type of repair. METHODS: The study cohort included all men referred to a vascular network with a large abdominal aortic aneurysm (AAA). Basic demographic information, nurse assessment details, as well as outcome data were extracted from the national NAAASP IT system, AAA SMaRT, for analysis. RESULTS: Some 3 026 men were referred for possible intervention (48% first screen, 52% surveillance). Some 448 men (13.3%) either declined (63, 2.1%), or were turned down for early intervention for various reasons (385, 12.7%). Some 8% were declined for medical reasons (true turn down rate). Men referred from surveillance were older, and more likely not to have had elective surgery within three months (16.0 vs. 11.2%; HR 1.37, 95% CI 1.07-1.75, p = .011). Turn down rates did not vary among local programmes, when surveillance men were taken into account. Some 2 624 (87%) men had planned AAA repair, with a peri-operative mortality of 1.3%. Thirty day surgical mortality was lower after EVAR: 0.4% compared with 2.1% after open repair. The method of repair remained consistent year on year, with roughly equal numbers undergoing endovascular (50%) and open surgical repair (48%); 2% unknown. There was regional variation in the proportion treated by endovascular repair: from 20% to 97%. CONCLUSION: The turn down rate after referral for treatment with a screen detected AAA was low, but there remains considerable regional variation in the proportion undergoing endovascular repair. Procedures were undertaken with low peri-operative mortality.

Safety of Men With Small and Medium Abdominal Aortic Aneurysms Under Surveillance in the NAAASP.

BACKGROUND: Population screening for abdominal aortic aneurysm (AAA) has commenced in several countries, and has been shown to reduce AAA-related mortality by up to 50%. Most men who screen positive have an AAA <5.5 cm in diameter, the referral threshold for treatment, and are entered into an ultrasound surveillance program. This study aimed to determine the risk of ruptured AAA (rAAA) in men under surveillance. METHODS: Men in the National Health Service AAA Screening Programme who initially had a small (3-4.4 cm) or medium (4.5-5.4 cm) AAA were followed up. The screening program's database collected data on ultrasound AAA diameter measurements, dates of referral, and loss to follow-up. Local screening programs recorded adverse outcomes, including rAAA and death. Rupture and mortality rates were calculated by initial and final known AAA diameter. RESULTS: A total of 18 652 men were included (50 103 person-years of surveillance). Thirty-one men had rAAA during surveillance, of whom 29 died. Some 952 men died of other causes during surveillance, mainly cardiovascular complications (26.3%) and cancer (31.2%). The overall mortality rate was 1.96% per annum, similar for men with small and medium AAAs. The rAAA risk was 0.03% per annum (95% CI, 0.02%-0.05%) for men with small AAAs and 0.28% (0.17%-0.44%) for medium AAAs. The rAAA risk for men with AAAs just below the referral threshold (5.0-5.4 cm) was 0.40% (0.22%-0.73%). CONCLUSIONS: The risk of rAAA under surveillance is <0.5% per annum, even just below the present referral threshold of 5.5 cm, and only 0.4% of men under surveillance are estimated to rupture before referral. It can be concluded that men with small and medium screen-detected AAAs are safe provided they are enrolled in an intensive surveillance program, and that there is no evidence that the current referral threshold of 5.5 cm should be changed.

Update on the prevention of death from ruptured abdominal aortic aneurysm.

Objectives To monitor the early effect of a national population screening programme for abdominal aortic aneurysm in 65-year-old men. Setting The study used national statistics for death rates from abdominal aortic aneurysm (Office of National Statistics) and hospital admission data in England (Hospital Episode Statistics). Methods Information concerning deaths from abdominal aortic aneurysm (ruptured and non-ruptured) (1999-2014) and hospital admissions for ruptured abdominal aortic aneurysm (2000-2015) was examined. Results The absolute number of deaths from abdominal aortic aneurysm in men and women aged 65 and over has decreased by around 30% from 2001 to 2014, but as the population has increased, the relative reduction was 45.6% and 40.0%, respectively. Some 65% of all abdominal aortic aneurysm deaths are in men aged over 65; women aged 65 and over account for around 31%. Deaths from ruptured abdominal aortic aneurysm in men aged 60-74 (the screened group) appear to be declining at the same rate as in men aged 75 and over. The relative decline in admissions to hospital with ruptured abdominal aortic aneurysm may be greater in men and women aged 60-74 (which contains the screened group of men), than those older, giving the first possible evidence that abdominal aortic aneurysm screening is having an effect. Conclusion The death rate from abdominal aortic aneurysm is declining rapidly in England. There is the first evidence that screening may be contributing to this reduction.