Coagulopathy and haemostasis in surgery for abdominal aortic aneurysm

• Main Author: Milne, Alan Anderson
• Published: University of Edinburgh 1995
• Subjects: 617
• Online Access: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.657819

Coagulation studies were performed in a series of 24 patients with asymptomatic abdominal aortic aneurysm. Levels of fibrinogen were high but within the normal range, and there was no evidence of systemic activation of the soluble coagulation or fibrinolytic systems. Coagulation studies were performed in a series of six patients undergoing elective aortic aneurysm repair. It was found that thrombin, fibrinolytic and platelet activation increases during the period of initial dissection in a time dependent manner. After the administration of heparin and the application of the aortic cross clamp, thrombin, fibrinolytic and platelet activation reduced. After reperfusion there was an increase in platelet activation which correlated with the duration of cross-clamping. Coagulation studies were performed in a series of 22 patients presenting with ruptured aortic aneurysm. At time of admission there was marked activation of platelets and thrombin in all patients which increased greatly by the end of operation. Platelet count at the end of operation was significantly lower in patients who died than in survivors. Samples of subcutaneous fat and skeletal muscle were taken at the start of operation in six patients with ruptured aneurysm. Transmission electron microscopy was used to examine the endothelial cells in small vessels in these samples. When compared with samples from six control patients undergoing elective aortic surgery it was found that there were significant ultrastructural differences in the endothelial cells from patients with rupture. A randomised controlled study of fibrin sealant as a topical haemostatic agent at vascular anastomoses was carried out in 57 patients undergoing aortic aneurysm repair, carotid endarterectomy or arterial bypass graft using polytetrafluoroethylene bypass graft. The time taken to achieve haemostasis at the anastomoses was significantly reduced in patients treated with fibrin sealant. The reduction was most marked in patients undergoing carotid endarterectomy.