Endotoxin related early neutrophil activation is associated with outcome after thoracoabdominal aortic aneurysm repair

Background Thoracoabdominal aortic aneurysm (TAAA) repair is associated with high mortality rates, especially in patients who develop postoperative renal and pulmonary impairment. Organ damage during TAAA repair may be mediated by activated polymorphonuclear neutrophils (PMNs) during a systemic inflammatory response. The association between intraoperative neutrophil activation and postoperative outcome was studied after TAAA surgery. Methods Perioperative PMN activation (surface CD 11b expression by flow cytometry), plasma endotoxin, plasma endotoxin core antibody, tumour necrosis factor (TNF), and interleukin 1 (IL‐1) levels were measured in 21 patients undergoing TAAA repair. Results Intraoperative PMN CD11b expression was significantly greater in the 11 patients who developed pulmonary and renal complications than in those who made an uneventful recovery (P=0.0009). In addition, CD11b expression during visceral reperfusion was preceded by a rise in plasma endotoxin level and a fall in antibody level (reflecting binding by absorbed endotoxin) which was significantly greater in patients who developed complications (P = 0.031 and P = 0.001 respectively). Plasma endotoxin level correlated with CD11b expression (r = 0.828, P=0.001). There were no significant differences in intraoperative plasma levels of TNF and IL‐1, or aortic cross‐clamp times and blood transfusion volumes between the complicated and uncomplicated repairs. Conclusion Intraoperative neutrophil activation is a marker for the development of postoperative complications after TAAA reconstruction and is associated with endotoxin absorption.