The Effects of Administration of Exogenous Albumin Early after Non-cardiac Surgery on Postoperative AKI in Patients with Preoperative Hypoalbuminemia: A Prospective Propensity-score Matching Analysis

Background: Evidence has shown that preoperative hypoalbuminemia is independently associated with acute kidney injury (AKI) after non-cardiac surgery. However, little study has investigated the effects of administration of exogenous albumin early after non-cardiac surgery on postoperative AKI in patients with preoperative hypoalbuminemia.Methods: This study was a secondary analysis of the database of a previously conducted prospective cohort study. Data of 661 adult patients who underwent non-cardiac surgery and were admitted to Surgical Intensive Care Unit (SICU) after surgery from May 1, 2019, to November 30, 2020, were collected. 267 patients with preoperative hypoalbuminemia were screened, and divided into two groups according to whether they were administrated with exogenous albumin on the day of SICU admission. The demographic and perioperative data of the two groups were propensity-matched.Results：After propensity score matching, 64 pairs of patients were included in the final analysis. The patients of the albumin group showed a higher serum albumin level on postoperative day 1 than that in patients of the control group [31.3±3.4 vs. 29.7±3.8, P=0.008], however, no difference was observed in postoperative AKI incidence between the two groups (59.4% vs. 62.5%, P=0.717). Furthermore, there was no difference in other prognostic factors, such as the use and duration of mechanical ventilation, number of other postoperative complications, in-hospital mortality, length of SICU stay and postoperative hospital stay.Conclusions: The current study did not exhibit benefit of exogenous albumin administration early after non-cardiac surgery on the occurrence of postoperative AKI in patients with preoperative hypoalbuminemia, which needs to be confirmed by further large randomized controlled researches in the future.