Postoperative delirium in the intensive care unit predicts worse outcomes in liver transplant recipients

BACKGROUND: Delirium is common in intensive care unit patients and is associated with worse outcome. OBJECTIVE: To identify early risk factors for delirium in patients admitted to the intensive care unit following orthotopic liver transplantation (OLT). METHODS: An observational study of patients admitted to the intensive care unit from January 2000 to May 2010 for elective or semi-elective OLT was conducted. The primary end point was delirium in the intensive care unit. Pre- and post-transplantation and intraoperative factors potentially associated with this outcome were examined. RESULTS: Of the 281 patients included in the study, 28 (10.03%) developed delirium in the intensive care unit at a median of two days (interquartile range one to seven days) after OLT. According to multivariate analysis, independent risk factors for delirium were intraoperative transfusion of packed red blood cells (OR 1.15 [95% CI 1.01 to 1.18]), renal replacement therapy during the pretransplantation period (OR 13.12 [95% CI 2.82 to 72.12]) and Acute Physiologic and Health Evaluation (APACHE) II score (OR per unit increase 1.10 [95% CI 1.03 to 1.29]). Using Cox proportional hazards models adjusted for baseline covariates, delirium was associated with an almost twofold risk of remaining in hospital, a fourfold increased risk of dying in hospital and an almost threefold increased rate of death by one year. CONCLUSION: Intraoperative transfusion of packed red blood cells, pretransplantation renal replacement therapy and APACHE II score are predictors for the development of delirium in intensive care unit patients post-OLT and are associated with increased hospital lengths of stay and mortality.