Subjects: patients who planned to undergo elective major abdominal surgery.~Study data collection period: Subjects signed the consent form until 28 days after discharge or died in hospital or withdrew from the study.~Number of research centers/sample size: 3400 patients were planned to be included.~Study process: Among patients undergoing elective surgery, the researchers will include patients who meet the inclusion criteria for elective major abdominal surgery and agree to participate in the study. The data to be collected in this study will be recorded by the researcher in the eCRF, including:~(1) Data to be collected during the screening period and preoperatively: patients' basic characteristics and demographic data (2) Data to be recorded during and/or after surgery: primary study indicators, secondary indicators, and other indicators.
Title: Effects of Sodium Bicarbonate Ringer's Injection and Sodium Lactated Ringer's Injection on postoperative acute kidney injury in patients undergoing major abdominal surgery: a randomized, controlled, open-label clinical study~Objective: To evaluate the effect of BRS and LRS infusion on acute renal injury in patients undergoing major abdominal surgery~Primary outcome: Incidence of AKI at 28 days postoperative (defined as acute kidney injury, according to Kidgo 2012 definition and classification).~Study Design: Randomized, controlled, open-label clinical study.