The Effect of Preoperative Hydration on Cardiac Surgery-Associated Acute Kidney Injury

Objective: The aim of this study was to determine the effect of preoperative intravenous saline hydration on postoperative renal functions and the prevention of acute kidney injury subsequent to open-heart surgery. Methods: Our investigation was designed as a prospective, randomized, and controlled single-center trial. We included 110 patients with basal renal functions that were not disrupted and who were undergoing cardiac surgery from October to December 2020. The first group (control) had fluid restriction for 12 hours prior to surgery (n = 55), and the second group (case) was hydrated with 0.9% normal saline for 12 hours before surgery (n = 55). Results: In the hydration group, creatinine values dropped below the preoperative values (P = 0.008) and the glomerular filtration rate values rose above the preoperative levels (P = 0.003). The early-term mortality rates were 0% for the hydration group and 5.45% for the control group (n = 3). Besides, in the hydration group, the glomerular filtration rate values on the 30^th day and 360^th day after surgery increased to levels even higher than those recorded preoperatively. Conclusions: As a result of much effort, we showed that preoperative hydration can prevent severe cardiac surgery-associated acute kidney injury and related in-hospital mortality.