The NVR is commissioned by the Healthcare Quality Improvement Partnership (HQIP) as part of the National Clinical Audit and Patient Outcomes Programme and is designed to support quality improvement within NHS hospitals performing vascular surgery by providing information on their performance.
The report provides data on the major vascular interventions:
1) Repair of aortic aneurysms:
a. elective infra-renal
b. ruptured infra-renal
c. complex aneurysms
2) Carotid endarterectomy
3) Lower limb revascularisation (bypass and endovascular)
4) Major lower limb amputation
Areas of excellence in this year’s report were:
Areas for improvement were:
1) Elective infra-renal AAA
The provision of services for the repair of elective infra-renal AAA has been the subject of a Quality Improvement Programme supported by the VSGBI. Acknowledging the importance of case volume in driving better clinical outcomes, many regional vascular services have been reconfigured in a hub-and-spoke system.
The NVR received detailed information on 4,153 elective AAA repairs in 2016 (5% decrease in activity since 2015).
The proportion of cases performed by open repair (OR) and endovascular repair (EVAR) is similar to the previous 2 years (30% OR, 70% EVAR).
Most centres continue to achieve good performances for the majority of patients.
Areas of potential improvement highlighted by the report were:
2) Complex Aneurysm Repair
There were 2,055 complex AAA repairs:
The endovascular procedures included:
Outcomes remain favourable for EVAR compared to OR (in-hospital mortality of 3.5% and 18.4%, respectively). Direct comparison of these figures is difficult and the open procedures may represent a more complex anatomical AAA to repair. Further work is required to clarify which patients benefit most from an endovascular approach or an open repair.
Complex aortic surgery remains a relatively high risk, high cost service. Centres should only be commissioned to perform such procedures if they have submitted complete and accurate data to the NVR to ensure the provision of safe and effective services. 57 of the 76 centres performing complex AAA repairs in 2014-2016 submitted fewer than 10 cases per year.
3) Ruptured AAA
Despite the national screening programme, the number of aneurysm ruptures remains high, with 2,913 cases over the 3-year period.
The choice of endovascular repair remains static (approximately 30% compared to 70% for elective repair) for ruptured AAA despite clinical trial evidence of benefit from EVAR.
Over 80% of patients who had an OR required level 3 critical care after the procedure (median length of stay of 4 days). There were also a greater proportion of patients who returned to theatre within their hospital admission, and who suffered from respiratory problems.
Patients undergoing EVAR for ruptured AAA had a lower reported in-hospital postoperative mortality compared to OR (23.2% and 41.2%, respectively). Direct comparison of these figures is difficult and the open procedures may represent the more complex cases.
All NHS trusts demonstrated postoperative mortality rates within the expected range, given the number of procedures performed.
The report recommends that vascular units performing emergency AAA repair should ensure they are able to provide endovascular services 24/7 days a week, with appropriate skill mix, hybrid operating facilities and endovascular consumables.
There were a total of 4,330 carotid interventions. The number of procedures recorded in the NVR has decreased significantly (a 15% drop in two years). This seems to reflect a fall in activity rather than a reduction in case-ascertainment.
The median time from symptom to surgery is unchanged in 2016 (median: 13 days). However, there remains significant variation between NHS trusts, with the median delay ranging from 5 days to over 70 days.
Surgical outcomes continue to be good and estimated rates of significant complication are low (see full report for more details).
Areas of improvement highlighted by the report are:
Lower Limb Interventions for Peripheral Artery Disease
1) Lower limb bypass
NHS hospitals submitted 17,200 open surgical/bypass procedures to the NVR:
The outcomes for lower limb bypass are in line with recent literature, however the observed 10% unplanned readmission rate suggests this is an area for improvement.
2) Endovascular lower limb procedures
Overall, there were good clinical outcomes with an in-hospital mortality rate of 1.6% and a complication rate of 5.7%.
3) Major lower limb amputation
Over the three-year data collection period, 9,804 major lower limb amputations were entered into the NVR (with a yearly increase in estimated case ascertainment from 53% to 59%).
Elisa Dedola, Ronelle Mouton & Adam Pichel
Research and Audit Committee, VASGBI, February 2018