Oxidative stress during abdominal aortic aneurysm repair--biomarkers and antioxidant's protective effect: a review.

BACKGROUND AND OBJECTIVES Oxidative stress during abdominal aortic aneurysm (AAA) repair is likely to result as a response to an ischemia-reperfusion injury (IRI) to the lower limbs and gastrointestinal tract. This paper reviews the oxidative stress during AAA repair, with specific reference to biological markers and the potential antioxidant's protective effect. EVIDENCE AND INFORMATION SOURCES The current literature (1966 to July 2010) was reviewed specifically for all articles describing human studies relevant with the particular subject: oxidative stress in patients with AAA repair. Key-words used as single or combined searches included "abdominal aortic aneurysm", "open repair", "EVAR", "oxidative stress", "oxidation" and "antioxidant". RESULTS A total of 14 relevant human studies were identified. In the majority of studies all samples (blood samples or/and muscle biopsies) were obtained from the patients using regional sampling techniques before or after anaesthesia, during aortic clamping or balloon occlusion (ischemic time) and after aortic clamp removal (reperfusion time) in different time intervals up to 24 or 48 hours. The oxidative status during AAA repair operation was evaluated by measuring quantitative changes of different substances including mainly vascular endothelial adhesion molecules, lipid peroxidation by-products or reactive oxygen species (ROS) and their metabolites. Two studies compared two groups of patients with AAA treated either by open or endovascular repair (EVAR), while four studies used different types of antioxidant supplementation in order to correlate it with a reduction in oxidative stress and damage in the antioxidant group of patients. PERSPECTIVES AND CONCLUSIONS Current evidence suggests that there is a high-grade oxidative stress during AAA repair operation. This was higher in cases of open repair beside EVAR and in cases with ruptured AAAs beside elective cases. The beneficial effect of an antioxidant supplementation in reducing the oxidative stress during AAA repair was also demonstrated. The use of a biological marker as a predictor of the development of systemic complications could also give a therapeutic advantage.