摘要Background: It was believed that inflammatory response induced by cardiopulmonary bypass (CPB) was blamed for complications after cardiac surgery.To improve the outcome, many pharmacological interventions have been applied to attenuate inflammatory response during CPB.The objective of this study was to investigate the effect ofulinastatin (urinary trypsin inhibitor [UTI]) on outcome after CPB surgery.Methods: Totally, 208 patients undergoing elective valves replacement between November 2013 and September 2014 were divided into Group U (n =70) and Group C (n =138) based on they received UTI or not.Categorical variables were compared between groups using Fisher's exact test, and continuous variables using unpaired Student's t-test or Mann-Whitney U-test.One-way analysis of variance and Dunnett's or Tukey's tests were used to compare values at different time points within the same group.The risk of outcomes was estimated and adjusted by multivariable logistic regression, propensity scoring, and mixed-effect models for all measured variables.Results: Both the serious complications in total, including death, acute lung injury, acute respiratory distress syndrome and acute kidney injury, and the other complications, including hemodialysis, infection, re-incubation, and tracheotomy were similar between the two groups (P ＞ 0.05).After adjusted by multivariable logistic regression and the propensity score, UTI still cannot be found any benefit to improve any outcomes after cardiac surgery.Also, no statistical differences with regard to duration of postoperative mechanical ventilation, the length of Intensive Care Unit and hospital stays (P ＞ 0.05).Conclusion: UTI did not improve postoperative outcomes in our patients after cardiopulmonary bypass surgery.