Acute Kidney Injury in Patients Undergoing Open Abdominal Aortic Aneurysm Repair: A Pilot Observational Trial.

OBJECTIVES: Acute kidney injury (AKI) is a frequent complication after open repair of abdominal aortic aneurysms (AAA). Little research has been done to determine whether intraoperative hemodynamic events may precipitate AKI. Novel biomarkers also may aid in the earlier diagnosis of AKI. DESIGN: A pilot prospective observational trial. SETTING: A single tertiary academic medical center. PARTICIPANTS: Participants were 40 adult patients undergoing open repair of infrarenal AAA. INTERVENTIONS: Intraoperative hemodynamic monitoring of heart rate, mean arterial pressure, central venous pressure, and cardiac index was performed on a continuous basis. Blood samples were obtained at baseline and at 24 hours postoperatively for inflammatory biomarkers, including neutrophil gelatinase-associated lipocalin (NGAL). MEASUREMENTS AND MAIN RESULTS: AKI occurred in 20% of patients (8 of 40). Hypotension, including duration (defined as the length of time mean arterial pressure was<65 mmHg) and magnitude (the area under the curve of a mean arterial pressure<65 mmHg), was the only factor associated with postoperative AKI. Urinary NGAL at the conclusion of surgery had excellent ability to predict the development of AKI (area under the curve 0.84, 95% confidence interval = 0.70-0.97). The cytokines pentraxin 3 (PTX3), interleukin-1 receptor antagonist (IL1-RA), macrophage chemotactic protein (MCP), suppressor of tumorigenicity 2 (ST-2), and interleukin-10 (IL-10) also had good ability to predict the development of AKI in the immediate postoperative period. CONCLUSIONS: AKI occurs frequently in patients undergoing open repair of AAA. Intraoperative hypotension was the only factor that predicted the development of subsequent AKI. Urinary NGAL and several novel inflammatory biomarkers demonstrated good ability to predict its development. Novel biomarkers also may aid in the early diagnosis of AKI.