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Vascular surgery by numbers.

There are a number of pressures on vascular specialists in the UK to centralise the delivery of their services. These include political pressure from a Government that has just completed re-organisation of cancer services into Centres and Units based on populations of over one million. There is scientific evidence that concentrating expertise improves the results of high-risk, low-volume cancer surgery. Additionally, in vascular disease, evidence is becoming stronger of a similar volume-outcome effect concerning interventions for abdominal aortic aneurysm (AAA) and carotid disease.1,2 
 
Change is also being driven by advances in the delivery of vascular interventions. These increasingly move away from open surgery towards small incision, endovascular procedures that require skills which were formerly taught only to radiologists. Sharing of expertise and training may best be delivered by concentration of surgical and radiological expertise in larger units with an appropriate skill mix. 
 
A third pressure on the horizon is the possible introduction of a national AAA screening programme in the UK. This has been endorsed by the National Screening Committee and now awaits the views of Government, and (no doubt a fierce) debate about financial support. Fundamental to the benefit of an AAA screening programme is low-risk intervention. One solution might be to centralise the delivery of vascular intervention in 50–60 higher volume hospitals, but the financial cost of providing the infrastructure to achieve this in the short term is likely to be prohibitive.