The growth rate of AAA was significantly greater in women than in men. This may have implications for the frequency of follow-up and timing of repair of AAA in women.
Heparin does not increase blood loss or the need for blood transfusion during surgery. Heparin is not necessary to prevent distal thrombosis when the aorta is cross clamped. The results of the study are consistent with the known mechanisms leading to intraoperative MI and strategies for its prevention. Intravenous heparin, given before aortic cross clamping, is an important prophylaxic against perioperative MI in relation to AAA surgery.
It remains the minority of patients who have elective operation before the onset of symptoms and/or rupture. Despite anaesthetic and surgical specialization, the results of AAA repair have not improved over the past two decades. Operative mortality may be increasing, possibly because of the increasing age and associated comorbidity of the patients presenting to this unit.
Abdominal aortic aneurysms (AAAs) smaller than 55 mm in maximum anteroposterior diameter, as measured by ultrasonography, have a rupture rate of no more than 1 per cent per annum 1 . Despite various speculative calculations, the rupture rates for larger aneurysms are still unknown. Conventional (open) transabdominal surgical repair of an AAA carries a true overall operative mortality rate of about 8 per cent, but most major vascular surgical centres claim rates of less than 5 per cent. The trade-off between immediate operative death and fortuitous death from aneurysm rupture is perplexing. Elective repair is usually recommended for aneurysms greater than 55 mm in diameter. Patients who survive open AAA surgery have a residual lifetime risk of death from prosthetic infection, aortoenteric ®stula, and anastomotic and new aneurysm rupture that is unknown but probably less than 10 per cent.Endovascular repair of AAA was ®rst attempted by Parodi in Argentina in 1991. In the intervening 10 years a plethora of customized and commercial prostheses has been deployed in thousands of patients around the world. Proprietary devices have promptly been withdrawn as appliance failures ensued ± some to be redesigned, reintroduced and recalled again. No prosthesis has remained in continuous unmodi®ed use for long.The technical feasibility of endoluminal AAA repair decreases with increasing aneurysm diameter. In published series aneurysm diameters have often been reported (inappropriately for non-parametric data) as mean values; median diameters have not been disclosed, perhaps advisedly. The aneurysm diameters in large series suggest that at least half of the aneurysms subjected to endovascular operation have been less than 55 mm in diameter, as measured by computed tomography (CT) 2,3 . Some series from individual centres contain an even greater proportion of small aneurysms 4 . The CT measured any plane diameter is usually greater than the ultrasonographically measured maximum anteroposterior diameter. A majority of endovascular AAA operations performed to date have probably been in patients who had an annual risk of aneurysm rupture of less than 1 per cent.The overall operative mortality rate attributable to endovascular AAA surgery is unknown. Many more prostheses have been sold than can be accounted for in voluntary operation registers; compulsory preprocedure registration and totally independent audited follow-up are glaring omissions. Single-centre reports by enthusiasts are well known to paint an overoptimistic picture, and this, combined with reporting and publication bias, suggests strongly that published results provide¯awed guidance.The small AAAs most suited to endovascular repair are those that are easiest to repair by conventional methods, and there is no reason to suppose that the primary operative mortality rate of the two techniques is substantially different. Within 1 month of endoluminal AAA repair, 2± 16 per cent of patients require conversion to open operation and further conversions accrue as follow-up conti...
Skin cancer was found in 31 of 598 patients transplanted in Oxford. No cases occurred during the first 3 years after transplantation but the prevalence rose after 12 years to 18.2 per cent. The main risk factors predisposing to skin cancer were the time after transplantation and male sex. Comparison with data from other centres suggests that exposure to ultraviolet light is a major aetiological factor in the speed of development of skin cancer. As the incidence of new cases rose progressively with time in our patients, it would seem that skin cancer is likely to become a major clinical problem as more patients enjoy prolonged survival after renal transplantation. Preventative and screening measures should be taken by transplant units both in the UK and in other countries with similar temperate climates.
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