Objective  To analyze the risk factors and predictors related to postoperative delirium(POD) in liver transplantation.

  Methods  The clinical data of 232 liver transplant recipients were retrospectively analyzed. Recipients were assigned to POD group (n=60) and non-POD (n=172) group according to the presence of POD. The intra- and post-operative conditions were compared between the two groups of liver transplant recipients. The risk factors for occurrence of POD in liver transplant recipients were analyzed using multifactorial analysis. And the value of predicting the occurrence of POD in liver transplant recipients according to the risk factors were assessed.

  Results  The incidence of POD in liver transplant recipients was 25.9%. The operation time and anhepatic phase in the POD group were longer than those in the non-POD group. Intraoperative infusion of erythrocyte, infusion of cryoprecipitate, and lactic acid level were higher than those in the non-POD group (all P < 0.05). The levels of postoperative alanine aminotransferase (ALT), aspartate aminotransferase (AST), prothrombin time international normalized ratio (PT-INR), and plasma fibrinogen in the POD group were significantly higher than those in the non-POD group (all P < 0.05). Preoperative hepatic encephalopathy, elevated blood ammonia, high score of model for end-stage liver disease (MELD), elevated postoperative AST level and long intraoperative anhepatic phase were the independent risk factors for POD in liver transplant recipients (all P < 0.05). Preoperative elevated blood ammonia and high MELD score showed profound value in predicting the occurrence of POD in liver transplant recipients, with best cut-off values of 42.6 μmol/L and 18 points, sensitivity of 0.650 and 0.767 as well as specificity of 0.826 and 0.727, respectively.

  Conclusions  The incidence of POD is high in liver transplant recipients. Preoperative hepatic encephalopathy, elevated blood ammonia, high MELD score, elevated postoperative AST level, and long intraoperative anhepatic phase are independent risk factors for liver transplant POD. Preoperative elevated blood ammonia and high MELD score are predictors of POD in transplant recipients.