Suprarenal aortic cross-clamping in elective abdominal aortic aneurysm surgery.

Abstract

this retrospective study was undertaken to evaluate whether suprarenal aortic cross-clamping increased the perioperative mortality and morbidity as compared to infrarenal clamping, in order to create the rationale for a more extensive application of this apparently more traumatic manoeuvre. in a series of 734 elective aortic substitutions for abdominal aneurysm (AA), performed consecutively from January 1992 to June 1999, aortic cross-clamping was performed at a suprarenal level in 56 juxtarenal aneurysms, i.e. aneurysms extending to the lower edge of the renal arteries (8%, Group 1), and at an infrarenal level in 634 subrenal aneurysms (92%, Group 2). When analysing preoperative data, the diameter of aneurysms was larger in Group 1 than in Group 2 (p<0. 005). No significant differences were found between the two groups as regards age, sex, postinfarction cardiomyopathy, chronic obstructive pulmonary disease, chronic renal insufficiency and ASA classification of operative risks. the average time of renal exclusion in the juxtarenal aneurysms was 20 min (range 12-35 min). There is no difference between the two groups as regards the time of aortic clamping (mean 50 vs. 60 min) or the need for homologous blood transfusion (7% vs. 11% of patients). Perioperative (30 days) mortality did not differ: 3.6% vs. 1.9% (n.s.); nor did the incidence of acute myocardial infarction (3.6% vs. 2.3%). Renal function deteriorated in 8 (14%) vs. 0 (0%) (p<0.001) and 1 patient (2%) required permanent dialysis, as compared to 0% in Group 2. The incidence of ischaemic colitis was also significantly higher in Group 1 (7%) than in Group 2 (2%, p<0.01). this data shows that suprarenal clamping, which is necessary for the radical treatment of juxtarenal aortic aneurysms, can be performed with a low risk.