Introduction : Post-operative delirium(POD) is one of the most common complication of major abdominal surgery. Although it is temporary and reversible, it is known to be related with the increased incidence of post-operative complications. The aim of this study was to figure out the incidence of POD in patients undergoing a major hepato-pancreato-biliary(HPB) surgery and to determine the risk factors of its development.

Methods : Patients over 20 years undergoing elective major HPB operations at the Center for Liver Cancer, National Cancer Center were prospectively enrolled. All patients were screened for delirium using the Korean Nursing Delirium Scale (Nu-DESC) and an independent psychiatrist assessed referred patients thereafter. Univariate and multivariate analysis were performed.

Results : 119 patients were enrolled with a median age of 63 years. The overall incidence of POD was 30.3% (36/119). The median onset was on the second post-operative day. Older age and lower mini-mental status exam(MMSE) score were predictive of an increased risk of POD. Patients who developed POD showed a tendency of an increased length of stay (19.7 vs 15.2), and an increased risk of developing grade 3 or higher complication (Clavien-Dindo classification).

Conclusions : In this study, we demonstrated that POD is associated with older age and low cognitive function test score.