Guidance

Executive summary

Updated 1 October 2024

The NHS Abdominal Aortic Aneurysm (AAA) Screening Programme standard operating procedures (SOP) are based on the original programme plan that provided the evidence and the basis for the UK National Screening Committee’s recommendation of a national programme. Deviations from the SOPs are seen as deviations from nationally set and agreed protocols. The national programme’s pathway standards and national IT solution are based on the SOPs. We welcome feedback on the SOPs and associated documents and will continue to develop them with stakeholders and local AAA screening programmes.

Local AAA screening providers need to have several important elements in place for screened individuals to receive a high quality, reliable, supportive and effective service. Local services must undertake core activities and fulfil several responsibilities to ensure high quality screening is available to their population.

Local providers are responsible for:

• coordinating and managing their service
• setting operational policy
• identifying and inviting eligible people
• providing information, support and advice for participants
• undertaking and reading screening tests
• recording results, scheduling follow-up surveillance scans and running failsafe systems
• referring for diagnostic investigations
• recording and monitoring the outcomes of interventions
• reporting on performance against pathway standards

1. AAA screening principles

The NHS AAA Screening Programme aims to reduce AAA-related mortality by providing a systematic population-based screening programme for the male population during their 65th year and, on request, for men over 65. An AAA is defined as a maximum aortic diameter of 3cm or greater in the maximum anterior-posterior measurement measured from the inner wall to inner wall. An aortic diameter of less than 3cm is deemed to be within normal limits.

The objectives of the NHS AAA Screening Programme are to:

• identify eligible men and invite them for screening
• provide clear, high quality information that is accessible to all, enabling men to make an informed choice about taking up the offer of screening
• carry out high quality abdominal ultrasound on those men attending for initial or follow-up screening according to national protocol
• minimise the adverse effects of screening, including anxiety and unnecessary investigations
• identify AAAs accurately
• enable men to make an informed choice about the management of their AAA
• ensure appropriate and effective management of cardiovascular risk factors of those with AAAs identified through screening
• ensure high quality diagnostic and treatment services
• promote audit and research and learn from the results

Screening for AAA refers to measuring the maximum aortic diameter on apparently well men to detect those with an AAA and then referral on to assessment and treatment for those who need it.

Public Health England (PHE) is committed to reducing mortality across England. The NHS AAA Screening Programme contributes to this through earlier detection of AAA by ensuring the provision of:

• an effective AAA screening programme for men at age 65
• a facility for screening on request for men over 65 who have not previously been screened
• rapid referral to a vascular unit for those meeting the criteria for considering treatment
• a surveillance programme and cardiovascular risk assessment for men with detected AAA who have not reached the criteria for referral
• referral to vascular assessment and treatment services that comply with guidance from the Vascular Society of Great Britain and Ireland (VSGBI) and from the UK National Screening Committee

The main guiding principles for the NHS AAA Screening Programme are that:

• all individuals should be treated with courtesy, respect and an understanding of their needs
• all those participating in AAA screening should have adequate information on the benefits and risks to allow an informed decision to be made before participating
• the target population should have equitable access to screening
• screening should be effectively integrated across a pathway including between the different providers, screening centres, primary care and secondary care

2. Vascular networks

The success of the screening programme in terms of outcomes for men is critically dependent on achieving the lowest possible morbidity and mortality from surgical interventions for those found to have an AAA warranting surgery or stenting. Approved intervention centres, clinical networks, standard operating procedures, participation in national audit and good patient information about risks and benefits all play a part in achieving this.

The VSGBI works closely with the national programme centre and Department of Health on the development of vascular networks and quality improvement processes. The criteria required for vascular networks linked to local AAA screening programmes and delivering interventions for screen-detected AAA are outlined in full on the VSGBI website