Risk factors of acute kidney injury after major elective abdominal surgery: A prospective observational study.

Background: In this prospective observational study, we aimed to determine the perioperative incidence and the risk factors of acute kidney injury after elective major abdominal surgery.

Methods: Adult patients who had undergone major elective abdominal surgery were included in the study. The patients were divided into Group AKI + and Group AKI, according to KDIGO criteria at 48 hours. Patients' demographic data, preoperative status, and laboratory data, operation-related data, and postoperative laboratory and follow-up data were noted. The patients were followed up for complications and mortality within three months after the operation date.

Results: In 425 patients included in the statistical analysis, the incidence of acute kidney injury after elective major abdominal surgery in our hospital was found to be 11.52% (49/425). In the multivariate analysis, postoperative continuation of vasopressor, mean arterial pressure <50 mmHg for at least 5 minutes, intraoperative 6% hydroxy-ethyl starch use, and high body mass index were found to be independent risk factors, in order of importance in increasing risk (OR 5.1, CI [1.4-18.9], P = 0,016; OR 3.9, CI [1.3-11.6], P = 0,014; OR 2.7, CI [1.1-6.8], P = 0,029; OR 1.2, CI [1.1-1.2], P < 0,001, respectively). 30- and 90-day mortality was found more frequently in patients who developed acute kidney injury.

Conclusions: In this study, we recommend modifying risk factors if possible, including avoiding 6% HES use and close blood pressure monitoring to reduce the incidence of postoperative acute kidney injury.