Abdominal Aortic Aneurysm: Diagnosis and Management

This Guidelines summary covers diagnosis, monitoring and reducing the risk of rupture, and emergency transfer to regional vascular services. This summary only covers recommendations for primary care. Please see the full guideline for complete recommendations on:

• imaging technique
• predicting and improving surgical outcomes
• repairing unruptured aneurysms
• repairing ruptured aneurysms
• monitoring for complications after endovascular aneurysm repair
• managing endoleaks after endovascular aneurysm repair.

Diagnosis

Identifying People at Risk of Abdominal Aortic Aneurysms

• Inform all men aged 66 or over who have not already been screened about the NHS abdominal aortic aneurysm (AAA) screening programme, and advise them that they can self-refer
• Encourage men aged 66 or over to self-refer to the NHS AAA screening programme if they have not already been screened and they have any of the following risk factors:
  • chronic obstructive pulmonary disease (COPD)
  • coronary, cerebrovascular or peripheral arterial disease
  • family history of AAA
  • hyperlipidaemia
  • hypertension
  • they smoke or used to smoke
• Consider an aortic ultrasound for women aged 70 and over if AAA has not already been excluded on abdominal imaging and they have any of the following risk factors:
  • COPD
  • coronary, cerebrovascular or peripheral arterial disease
  • family history of AAA
  • hyperlipidaemia
  • hypertension
  • they smoke or used to smoke
• Be aware that people of European family origin are at a higher risk of an AAA

Identifying Asymptomatic Abdominal Aortic Aneurysms

• Offer an aortic ultrasound to people in whom a diagnosis of asymptomatic AAA is being considered if they are not already in the NHS screening programme
• Refer people with an AAA that is 5.5 cm or larger to a regional vascular service, to be seen within 2 weeks of diagnosis
• Refer people with an AAA that is 3.0 cm to 5.4 cm to a regional vascular service, to be seen within 12 weeks of diagnosis
• Offer an aortic ultrasound to people with a suspected AAA on abdominal palpation

Identifying Symptomatic or Ruptured Abdominal Aortic Aneurysms

• Think about the possibility of ruptured AAA in people with new abdominal and/or back pain, cardiovascular collapse, or loss of consciousness. Be aware that ruptured AAA is more likely if they also have any of the following risk factors:
  • an existing diagnosis of AAA
  • age over 60
  • they smoke or used to smoke
  • history of hypertension
• Be aware that AAAs are more likely to rupture in women than men
• Offer an immediate bedside aortic ultrasound to people in whom a diagnosis of symptomatic and/or ruptured AAA is being considered. Discuss immediately with a regional vascular service if:
  • the ultrasound shows an AAA or
  • the ultrasound is not immediately available or it is non-diagnostic, and an AAA is still suspected

Providing Information to People With a Diagnosed AAA

• Give people with AAA of any size information explaining:
  • what an AAA is
  • that most AAAs do not cause any problems
  • that AAAs can rupture, and what this means
  • that AAAs are likely to get larger over time, and that larger AAAs are more likely to rupture
  • that AAA may run in families, so they should tell close relatives that they may have an increased risk of AAA and may need assessment (see Identifying people at risk of abdominal aortic aneurysms)
  • what options for aneurysm repair are available, when repair should be considered and the potential benefits and risks (see full guideline recommendations 1.5.1 and 1.5.2), and when it might be better to not have repair
  • their risk of cardiovascular disease and how this risk can be reduced (see full guideline recommendation 1.4.6), and see the section on identifying and assessing cardiovascular disease risk in the NICE guideline on cardiovascular disease)
• If AAA repair is not currently suitable for a person, explain why, based on their individual circumstances. For example:
  • small AAAs only have a very low chance of rupture and there are risks to aneurysm repair, so in this case people do not benefit from repair
  • AAA growth is unpredictable, so until their AAA meets the criteria (see full guideline recommendation 1.5.1) it is not possible to know whether repair will be suitable for a particular person
  • on average, people with poor overall health do not benefit from AAA repair. There is no reliable way to assess whether a particular person will benefit or be harmed, so repair for people with poor overall health is an unnecessary risk even if their AAA meets the criteria in full guideline recommendation 1.5.1

• Check that people understand their options, and give them time for reflection and discussion. Encourage them to discuss the options with their family and friends
• For more guidance on providing information, see the section on enabling patients to actively participate in their care in the NICE guideline on patient experience in adult NHS services

Monitoring and Reducing the Risk of Rupture

Reducing the Risk of Rupture

• Offer a referral to a stop smoking service to people with an AAA who smoke. For more guidance, see the NICE guideline on stop smoking interventions and services
• Ensure that people with an AAA who have hypertension receive care in line with the NICE guideline on hypertension in adults

Monitoring the Risk of Rupture

• Offer surveillance with aortic ultrasound to people with an asymptomatic AAA. Use the same surveillance frequency as the NHS AAA screening programme
• See Identifying asymptomatic abdominal aortic aneurysms on when to refer people to a regional vascular unit

Emergency Transfer to Regional Vascular Services

• Be aware that there is no evidence that any single symptom, sign or prognostic risk assessment tool can be used to determine whether people with a suspected or confirmed ruptured AAA should be transferred to a regional vascular service
• When making transfer decisions, be aware that people with a confirmed ruptured AAA who have a cardiac arrest and/or have a persistent loss of consciousness have a negligible chance of surviving AAA repair
• For guidance on care of people with a ruptured AAA for whom repair is considered inappropriate, see the NICE guideline on care of dying adults in the last days of life
• When people with a suspected ruptured or symptomatic unruptured AAA have been accepted by a regional vascular service for emergency assessment, ensure that they leave the referring unit within 30 minutes of the decision to transfer

• Emergency departments, ambulance services and regional vascular services should collaborate to:

  • provide a protocol for the safe and rapid transfer of people with a suspected ruptured or symptomatic unruptured AAA who need emergency assessment at a regional vascular service

  • train clinical staff involved in the care of people with a suspected ruptured or symptomatic unruptured AAA in the transfer protocol

  • review the transfer protocol at least every 3 years

Supporting People During Transfer

• Consider a restrictive approach to volume resuscitation (permissive hypotension) for people with a suspected ruptured or symptomatic AAA during emergency transfer to a regional vascular service