Perioperative risk factors of acute kidney injury after non-cardiac surgery: A multicenter, prospective, observational study in patients with low grade American Society of Anesthesiologists physical status.

BACKGROUND: The aim of this study was to determine the incidence and the perioperative risk factors of acute kidney injury (AKI) using "Kidney Disease: Improving Global Outcomes" (KDIGO) guidelines, in patients with low grade American Society of Anesthesiologists physical status (ASA-PS) undergoing non-cardiac surgery.

METHODS: In this multicenter, prospective, observational study, 870 surgical patients older than 40 years with ASA-PS I-II who underwent noncardiac surgery, were included. The primary outcome of this study was perioperative AKI defined by the KDIGO criteria.

RESULTS: AKI was detected in 49 (5.63%) of the patients. Multivariate analysis detected the presence of preoperative hypertension (aOR = 0.130; CI = 0.030-0.566; p = 0.007) and intraoperative transfusion of erythrocytes (aOR = 0.076; CI = 0.008-0.752; p = 0.028) as independent predictors of postoperative AKI development.

CONCLUSION: Approximately, 6% of patients with ASA I-II presenting for noncardiac surgery developed postoperative AKI. Preoperative hypertension and intraoperative erythrocyte transfusion are independent predictors of AKI after non-cardiac surgery in this patient population.