Incidence and risk factors of postoperative delirium in patients with esophageal cancer.

Postoperative delirium is a common complication after major surgery and is characterized by acute confusion with fluctuating consciousness. The aim of this study was to investigate the incidence and risk factors of postoperative delirium in patients with esophageal cancer. We conducted a retrospective cohort analysis of 306 consecutive patients who had undergone an esophagectomy at Keio University Hospital from January 1998 to December 2009. All data were assessed by psychiatrists, and delirium was diagnosed according to criteria of the Diagnostic and Statistical Manual Disorder, fourth edition. Univariate and multivariate analyses were performed. Postoperative delirium developed in 153 (50.0 %) of 306 patients. One hundred fourteen (37.3 %) of the 306 patients required psychoactive medication for symptoms associated with delirium. Univariate analyses showed that older age, male gender, additional flunitrazepam for sedation in intensive care unit (ICU) after surgery, longer periods of time under mechanical ventilation after surgery, longer ICU stays, occurrence of postoperative complications, and longer hospital stays were significantly associated with postoperative delirium. Multivariate analysis revealed that development of delirium was linked to older age, additional flunitrazepam in ICU, and occurrence of postoperative complication. The development of postoperative delirium in patients with esophageal cancer is a problem that cannot be ignored. Our results suggest that the risk of developing delirium is associated with older age, use of flunitrazepam in ICU, and postoperative complications.