HEMODYNAMIC AND METABOLIC RESPONSE TO ENDOVASCULAR REPAIR OF INFRARENAL AORTIC-ANEURYSMS

We have examined whether or not endovascular insertion of a bifurcated aorto-iliac graft resulted in greater intraoperative haemodynamic and metabolic stability than that achieved during conventional open graft placement. We studied 20 patients prospectively during surgery for as ymptomatic infra-renal aortic aneurysm. All patients received the same anaesthetic technique. Haemodynamic data were collected continuously using indwelling radial artery and pulmonary artery catheters, allowin g calculation of mean arterial pressure (MAP), cardiac output (CO) and systemic vascular resistance (SVR). Blood samples were obtained for m easurement of serum lactate concentrations. Variables were compared wi thin each group before and after specific critical events, namely occl usion of femoral or aortic blood flow, or both, and sequential reperfu sion of each lower limb. Patients undergoing open repair showed signif icant changes in CO, MAP and SVR related to aortic cross-clamping and lower limb reperfusion, and a significant increase in blood lactate co ncentration after distal tissue reperfusion. The only significant chan ges during endovascular repair were a transient increase in SVR second ary to application of the femoral artery clamps, and sequential decrea ses when each limb was reperfused. Endovascular aneurysm repair impose d significantly less intraoperative haemodynamic and metabolic stress on the patient compared with conventional open surgery.