Malondialdehyde as an indicator of oxidative stress during abdominal aortic aneurysm repair

Ischemia-reperfusion injury significantly contributes to abdominal aortic aneurysm (AAA)- related mortality and morbidity; therefore, we measured oxidative stress during open AAA repair and investigated any potential associations with intraoperative or perioperative events (aortic clamping time, blood loss, and the need to transfer to the intensive care unit). Blood samples were collected at specific time points from 53 patients undergoing open AAA repair: (1) before induction of anesthesia; (2) 15, 30, 60, and 120 minutes after aortic clamping; (3) 15 and 60 minutes after clamp removal; and (4) 24 hours postoperatively. Malondialdehyde (MDA) levels were measured by a spectrophotometric method. Baseline MDA values in patients with AAA were significantly higher than in controls (P < .0001). A positive correlation was found between preoperative MDA levels and the size of AAAs (Pearson correlation = 0.578, P < .001). No difference was observed in MDA levels between ruptured and nonruptured AAAs; however, when all symptomatic patients (ruptured and elective symptomatic AAAs, n = 18) were considered, there was a significant elevation in MDA levels (P < .001). There was also a significant increase in MDA values in patients transferred postoperatively to the intensive care unit (P < .001). Finally, a positive association was found between the duration of aortic clamping with MDA values at 15 and 60 minutes after declamping, but not after 24 hours (Pearson correlation = 0.467, P < .001). MDA levels may predict the postoperative course of elective and ruptured AAAs.