Fibrinolysis in open abdominal aortic aneurysm surgery

Abstract

Objective: Does open surgery for abdominal aortic aneurysm (AAA) influence fibrinolysis? Setting: University Hospital. Materials: Twenty-three consecutive patients underwent open AAA surgery. Blood from the cubital vein was sampled pre-, intra- and postoperatively. Intraoperatively blood was also sampled from the femoral vein. Main outcome Measures: ELISA-methodology was used for quantitative determination of tissue plasminogen activator (tPA) and human cross-linked fibrin degradation product (D-dimer) antigens as well as for quantification of plasminogen activator inhibitor-1 (PAI-1) activity. Results: Preoperatively D-dimer in AAA patients were higher than in 20 healthy age-matched controls ( p<0.001). tPA decreased after aortic clamping ( p<0.001) and declamping ( p<0.05) in cubital blood and increased 1 week postoperatively ( p < 0.01). PAI-1 increased both in cubital and femoral blood after aortic declamping ( p<0.01 and p<0.001 respectively). D-dimer increased in femoral blood during aortic clamping ( p<0.05) and reached its highest level 1 week postoperatively ( p<0.01). Blood loss and duration of aortic clamping showed significant co-variation with intraoperative values of PAI-1. Conclusions: These data indicate that the fibrinolytic system is activated preoperatively and inhibited during AAA surgery. Furthermore, a high fibrinolytic activity is seen 1 week after AAA surgery. Surgical trauma, ischaemia and reperfusion of the lower part of the body as well as increased inflammatory activity symbolized by the intraoperative increase of PAI-1 may be causative factors.