Time is brain for carotid endarterectomy

Carotid endarterectomy is the gold standard surgical intervention for stroke prevention in patients with symptomatic internal carotid stenosis. Early intervention is crucial for a good outcome. However, according to a recent UK audit from the Vascular Society and the Royal College of Physicians, two-thirds of patients face an unacceptable delay. Although there are examples of timely service provision from centres of excellence in the UK and elsewhere, it is thought that many countries are struggling to reduce the time to carotid surgery. However, few national data are available, and this country-wide audit is an important first step towards guiding improvements in services. Pooled analysis of data from randomised controlled trials indicates that carotid endarterectomy significantly reduces risk of stroke in patients with 50% or greater stenosis who have had a transient ischaemic attack (TIA) or previous non-disabling stroke. However, these benefits quickly diminish if surgery is not done within 14 days of symptoms. Thus, the UK National Institute for Health and Clinical Excellence has set a target treatment time of 14 days from symptom onset; the UK government's Stroke Strategy, by contrast, has set a more ambitious timeframe of 48 h. The results of the audit show that only 3% of patients had surgery within 48 h, and a third had surgery within 14 days. The median delay to surgery was 28 days; it is in these 28 days that recurrent strokes are most likely to occur. Although there has been considerable improvement since a previous round of this audit reported in 2008—at which time 30% of patients had to wait more than 12 weeks for surgery—there is still a long way to go. Delays in referral (40%), delays in patients seeking medical help (18%), and restricted availability of staff or operating theatres (18%) were flagged up as important reasons for waiting times of over 2 weeks. As highlighted in the report, continued education of the public about the urgency of seeking medical help for stroke and TIA and of health-care professionals about the importance of early referral could therefore reduce delays, as could improvements in access to surgical facilities. However, the most important cause of delay was not in patient presentation or time from symptoms to referral (median referral time was 8 days), but in time from referral to surgery, which, at a median of 19 days, is far too long. In many health-care trusts, an organisational change is needed to streamline the sequence of events—eg, referral to a stroke physician, imaging for stenosis, and referral to a surgeon—before surgery is booked. Compressing this sequence should ideally involve centralisation of stroke and TIA services in more regions around dedicated 24 h access clinics designed to provide multidisciplinary services. A reduction in delays is crucial to ensure effectiveness of surgery in patients with TIA or non-disabling stroke, but these benefits must be balanced against the potential risks of complications after early surgery. In general, the risk of recurrent stroke in the first few weeks after symptoms is much higher than the risk of surgical complications. At present, however, there is uncertainty about the potential risks of complications of surgery within the proposed 48 h timeline, and more research is needed to determine the optimum timing for intervention. Furthermore, for patients with more disabling strokes or with coexisting medical problems, for whom the risks of surgery are greater, a delay in intervention might be justified. Encouragingly, reported complications after surgery were low—eg, the 30-day rate of death or stroke was 1·8%, which is much lower than in previous studies. However, neurologists or stroke physicians were rarely involved in outcome assessments; moreover, data were voluntarily provided and 30% of procedures were not included in this round of the audit. Future audits should ensure full coverage of procedures; a mandatory national register in Sweden, for example, has provided the impetus for improvements in time to surgery from a median of 6 weeks to 12 days. Another concern was that too many centres operate on only small numbers of patients, and the audit calls for these centres to join other vascular centres, either through formal networks or through centralisation of services, to disseminate good practice and share expertise. Experts estimate that surgical intervention within the 14-day timeframe on appropriately selected patients could, over 5 years, prevent up to 200 strokes per 1000 patients. Progress is being made in reducing time to surgery in the UK and further reductions are expected in the future; a national audit is a key step towards this aim. Ultimately, however, there needs to be a culture change within health services, in the UK and elsewhere, to reduce delays and ensure optimum outcome of carotid endarterectomy.