Oxygen delivery-guided perfusion for the prevention of acute kidney injury: A randomized controlled trial

Abstract Objectives The reduction of postoperative acute kidney injury (AKI) in patients undergoing cardiopulmonary bypass (CPB) surgery using an oxygen delivery-guided perfusion strategy (DO2 strategy) for CPB management as compared to a fixed flow perfusion (conventional strategy) remains controversial. The purpose of this study was to determine whether a DO2 strategy would reduce the incidence of postoperative AKI in patients undergoing CPB surgery. Methods We randomly enrolled 300 patients undergoing CPB surgery. Patients were randomly assigned to a DO2 strategy (maintaining a DO2i value >300 mL/min/m2 through pump flow adjustments during CPB) or a conventional strategy (a target pump flow was determined based on the body surface area). The primary endpoint was the development of AKI. Secondary endpoints were red blood cell (RBC) transfusion rate and number of RBC units, intubation time, postoperative length of stay in the intensive care units and in the hospital, predischarge estimated glomerular filtration rate, and hospital mortality. Results AKI occurred in 20 patients (14.6%) in the DO2 strategy and in 42 patients (30.4%) in the conventional strategy (relative risk, 0.48; 95% CI, 0.30 to 0.77; P = .002). The secondary endpoints were not significantly different between strategies. In prespecified subgroup analysis of patients who had nadir Hct less than 23% and/or BSA less than 1.40 m2, the DO2 strategy appeared to be superior to the conventional strategy and the existence of quantitative interactions was suggested. Conclusions A DO2 strategy for CPB management was superior to a conventional strategy with respect to preventing the development of AKI.