BMJ 2014;348:g95 doi: 10.1136/bmj.g95 (Published 13 January 2014)
Page 1 of 2
EDITORIALS Surgery for ruptured abdominal aortic aneurysm Trial reports comparable short term survival after open or endovascular repair Martin Björck professor of vascular surgery Department of Surgical Sciences, Uppsala University, SE-75185 Uppsala, Sweden
Two therapeutic alternatives exist in a patient with ruptured abdominal aortic aneurysm: immediate open repair or imaging with computed tomography followed by endovascular aneurysm repair if anatomically possible or open repair if not. The main advantage of the immediate open repair strategy is that further imaging is not required, and speed may save life. Endovascular repair, on the other hand, is less invasive and can in most cases be done under local anaesthesia, avoiding the life threatening severe hypotension associated with general anaesthesia in a bleeding patient.
Here is a situation of true equipoise. Observational research from Switzerland suggests that both strategies give equally excellent results,1 2 and two small randomised controlled trials failed to show any difference in mortality.3 4 In a linked paper (doi:10.1136/bmj.f7661), Powell and colleagues report the results of the IMPROVE trial,5 a major scientific achievement. Conducting a large trial in this emergent situation is demanding, not least because informed consent can be difficult to obtain. The Mental Capacity Act makes randomising patients in the United Kingdom without informed consent possible, which is ethically sound when the patient has potentially life threatening hypotension, coupled with severe pain.6 The trial was well designed and compared two relevant clinical strategies. The authors report no difference between the two groups in the primary outcome of 30 day mortality. Patients were randomised on suspicion of ruptured abdominal aortic aneurysm, and only 10% of the patients crossed over to the non-assigned strategy. A compliance analysis and a sensitivity analysis excluding participants without confirmed rupture both confirmed the main findings. Pre-specified subgroup analysis, however, suggested that women do better after endovascular repair than open repair, and this was due to a high mortality in the female open repair group (57%). Furthermore, participants treated with endovascular repair were significantly more likely to be discharged home than were those who had open surgery (94% v 77%; P