Elective open suprarenal aneurysm repair in England from 2000 to 2010 an observational study of hospital episode statistics, Karthikesalingham et al PLOS One 2013; 8:1-10

Comments on: Elective open suprarenal aneurysm repair in England from 2000 to 2010 an observational study of hospital episode statistics.Karthikesalingahm et al PLOS One 2013; 8: 1-10by N Chinai, J Brennan, S Hardy, V Smyth, Charles McCollum on behalf of the VGNW Participants?It is unfortunate that this paper has been published as we fear that it is a comment on the poor quality of hospital episodes statistics (HES) in the UK rather than a report on outcomes following open repair of suprarenal aneurysms. The authors intended to publish results on complex open AAA repair equivalent to fenestrated EVAR, ?as a counterpart for the results of the GLOBALSTAR registry, which reported every FEVAR performed in the UK between 2007 and 2010?. This should include any AAA repaired using a suprarenal aortic clamp; 280 such repairs were identified as being performed in the North West of England only in the last five years. The Office of Procedures, Census and Surveys (OPCS) procedure code L19.3 used by Karthikesalingam et al identified only 793 patients over 10 years. This code is defined as ?replacement of aneurysmal segment of suprarenal abdominal aorta by an anastomosis of aorta to aorta?, if we add the authors exclusion for any patient where there is a reference to anastomosis involving the visceral or renal arteries, a strict interpretation of this code means that we could only include aneurysms involving the aorta above the coeliac axis and below the diaphragm (unless the authors intend to include thoracic aortic aneurysm). We identified six other codes that hospital coding clerks might have used for ?suprarenal abdominal aortic aneurysm AAA? (L19.2, L19.5, L21.2, L21.3, L21.5 and L23.6). We entirely agree that none of these codes, including L19.3, accurately describes an AAA that is perirenal or extends to involve the suprarenal aorta. The fact that the authors identified over 100 hospitals (they don?t say how many) undertaking this repair, with over 80% doing either none or one, clearly indicates that most hospitals are not using procedure code L19.3. The use of this code by a junior member of administrative staff in the coding department therefore determined whether patients were included in this report; one hospital undertook approximately 90 repairs and most none at all. Commissioners responsible for AAA repairs in the North of England were concerned to read this paper publishing mortality rates of over 15% throughout most of England with lower rates in London and the South East. For this reason we have looked at the data for mortality in the 280 AAA repairs classified as peri or suprarenal in the Vascular Governance North West (VGNW) database (a database reporting on over 6,000 elective repairs performed in the NW of England). There were 18 deaths in 280 procedures performed by 52 surgeons during 2007-12 giving a mortality of 6.4%. Clearly the code L19.3, as defined by the authors of this paper, has not detected these repairs. Finally, it is well known that during the 10 year period 2000-2010, HES data in the UK was highly unreliable. We recently analysed 115 patients with AAA rupture performed at the University Hospital of South Manchester (USHM) between January 2008 and December 2012. The procedure performed and their urgency was verified by checking the case notes. Fifteen (13%) of these procedures were not identified by the HES database, the majority being reported as elective by HES; which would have massively inflated our mortality for elective surgery. A further four patients on the HES database classified as ruptures had actually undergone elective repair. In total, therefore, 19 of 115 patients (16.5%) were misclassified by HES. Sadly, little reliance can be placed on this paper as the only conclusions that can be drawn are:1. OPCS procedure code L19.3 is used variably from hospital to hospital.2. HES data is an unreliable source for mortality in elective AAA surgery where the inclusion of only a few ruptures inflates mortality dramatically.What we find surprising is that the referees considering this paper were unaware of the variable use of OPCS codes from hospital to hospital or that HES data may be particularly unreliable for AAA repair.