Objective:To evaluate the relationship between blood transfusion factors (massive transfusion, transfusion of stored red blood cells and anhepatic transfusion) and early postoperative outcomes in the patients undergoing orthotopic liver transplantation.Methods:Patients with end-stage liver disease who underwent orthotopic liver transplantation and intraoperative blood transfusion from January 2021 to March 2022 in our hospital were retrospectively selected, and their clinical data were collected. The patients were divided into massive transfusion group (M group, total red blood cell transfusion ≥10 U) and non-massive transfusion group (NM group) according to the amount of intraoperative blood transfused. The patients were divided into fresh blood group (NS group) and stored blood group (S group, red blood cell storage time > 2 weeks) according to the storage time of red blood cells transfused. The patients were divided into transfusion in anhepatic stage group (group T) and nontransfusion in anhepatic stage group (group NT) according to whether blood was transfused in the anhepatic stage. Multivariate logistic regression, generalized linear model and generalized linear mixed model were used to analyze the relationship between blood transfusion factors and primary outcome measures (postoperative pulmonary complications, circulation overload, acute kidney injury, abdominal infection, thrombosis) and between blood transfusion factors and secondary outcome measures (duration of ICU stay, postoperative hospitalization, postoperative temperature ≥38.5 ℃ at any time point after surgery, postoperative liver and kidney function index, coagulation function index, platelet count and preoperative difference).Results:One hundred and six patients were enrolled in this study. The results of multivariate logistic regression analysis: Massive blood transfusion and infusion of stored blood were risk factors for postoperative pulmonary complications, massive blood transfusion was a risk factor for abdominal infection, Child-Turcotte-Pugh score for liver function and time of anhepatic phase were risk factors for postoperative acute kidney injury, Child-Turcotte-Pugh score was a risk factor for circulatory overload, and age and massive blood transfusion were risk factors for thrombosis ( P<0.05). The results of generalized linear model analysis: Intraoperative stored blood transfusion and blood transfusion during the anhepatic phase were risk factors for prolonged duration of ICU stay, massive blood transfusion, intraoperative stored blood transfusion and blood transfusion during the anhepatic phase were risk factors for prolonged hospitalization ( P<0.05), and there was no correlation between massive blood transfusion, intraoperative stored blood transfusion and blood transfusion during the anhepatic phase and temperature ≥38.5 ℃ at any time point after surgery ( P>0.05). The results of generalized linear mixed model analysis: There was statistically significant difference in the difference between preoperative and postoperative liver and kidney function indexes, coagulation function indexes and platelet counts in the patients with or without massive transfusion, stored blood transfusion or blood transfusion during the anhepatic phase ( P<0.05). Conclusions:Massive blood transfusion and infusion of stored blood are the main risk factors for early adverse outcomes after orthotopic liver transplantation in the patients.