Effect of prostaglandin E1 on ischemia-reperfusion injury during abdominal aortic aneurysm surgery

Objectives. Abdominal aortic aneurysm (AAA) surgery subjects the lower extremities to ischemia and reperfusion. Although it is not extensive or prolonged, ischemia of the lower extremities during aortic cross-clamping is gradually and steadily induced. We studied the effects of prostaglandin E-1 (PGE(1)) on ischemia-reperfusion injury of the lower extremities during AAA repair. Methods. During AAA surgery, two near-infrared spectroscopy probes were positioned on each calf muscle to monitor oxygen metabolism in the lower extremities. We also measured lactate concentration in both iliac veins. Results. Near-infrared spectroscopy signals responded sensitively to aortic cross-clamping and declamping. Lactate increased time-dependently during aortic cross-clamping. The continuous venous administration of PGE(1) (20 ng/kg per minute) inhibited the accumulation of lactate during aortic cross- clamping. Declamping of the first iliac artery resulted in a further but transient increase in ipsilateral venous lactate, which may be one component in the mechanism of declamping shock. Prostaglandin E-1 eliminated the transient increase in ipsilateral lactate. The administration of PGE(1) inhibited the contralateral accumulation of lactate after first declamping, and the lactate level decreased gradually before the second declamping. Conclusions. Prostaglandin E-1 seems to have a protective effect against ischemia-reperfusion injury of the lower extremities during AAA surgery.