Clinical risk factors associated with postoperative delirium and evaluation of delirium management and assessment team in lung and esophageal cancer patients

BACKGROUND Delirium is an acute change in cognition and concentration that complicates the postoperative course. Patients who suffer delirium after surgery have an increased risk of persistent cognitive impairment, functional decline, and death. Postoperative delirium is also associated with an increased length of hospital stay and higher costs. With the goal of preventing delirium in postoperative patients, we organized a medical team from the Delirium Management and Assessment Center (D-mac) at Okayama University Hospital in January 2012. The team members consisted of physicians, pharmacists, nurses, and clinical psychologists. METHODS We retrospectively reviewed the medical records of patients with delirium to examine risk factors related to the patients' background. RESULTS Fifty-nine postoperative patients with lung or esophageal cancer were investigated; 25% exhibited delirium during hospitalization. Multiple logistic regression analysis showed significant associations between the presence of delirium and a past history of delirium (odds ratio, 4.22; 95% CI, 1.10-16.2; p = 0.09) and use of benzodiazepine receptor agonists (odds ratio, 3.97; 95% CI, 1.09-14.5; p = 0.03). Intervention by the D-mac significantly reduced the rate of delirium episodes in lung cancer patients (p =0.01). Notably, prior to intervention, the incidence of delirium was 100% when three high-risk factors for delirium were present. In contrast, the incidence of delirium in patients with three high-risk factors decreased following implementation of the D-mac intervention. CONCLUSIONS These findings suggest that active participation by various staff in the medical team managing delirium had a marked therapeutic impact.