Detailed insight into the impact of postoperative neuropsychiatric complications on mortality in a cohort of cardiac surgery subjects: a 23,000-patient-year analysis.

OBJECTIVES: This study sought to evaluate the impact of postoperative delirium with/without cerebral ischemia on short- and long-term mortality in a large cohort of cardiac surgery patients. DESIGN: The study constituted a prospective cohort observation of patients following various cardiac surgery procedures. SETTING: The investigation was conducted in a single high-volume tertiary cardiac surgery center. PARTICIPANTS: Consecutive candidates for cardiac surgery (n = 8,792) from 2003 to 2008 were subjected to the following exclusion criteria: History of any psychiatric disorders, alcohol abuse and intake of psychoactive drugs and incomplete data. INTERVENTIONS: No additional interventions were performed, except for standard perioperative management. MEASUREMENTS AND MAIN RESULTS: 5,781 patients finally were assigned to cohorts depending on the presence of postoperative delirium with/without cerebral ischemia and then prospectively followed up over the median time of 46 months. Overall 30-day mortality in patients with delirium was 15.25%, including 6.43% of patients without and 38.46% of subjects with cerebral ischemia. After adjustment for more than 100 perioperative variables, short-term mortality was associated independently with delirium (OR = 3.735), stroke (OR = 5.698), hypertension (OR = 0.333), urgency of surgery (OR = 13.018), baseline plasma glucose and protein concentrations and blood transfusions (AUROC for the model 0.94). Long-term mortality in patients who developed delirium was 23.31%, including 15.2% of patients without and 44.62% of those with postoperative stroke. Long-term mortality independently corresponded with stroke (HR = 3.968), urgent surgery (HR = 27.643), baseline plasma glucose and protein concentrations, chronic obstructive pulmonary disease and blood transfusions. Impact of postoperative delirium was insignificant (p = 0.2). Compared to subjects with cerebral ischemia, death in patients only with delirium was less frequently of cardiovascular cause (p < 0.01). CONCLUSIONS: Delirium with/without cerebral ischemia significantly worsened the short-term prognosis. Stroke, yet not delirium, considerably increased the long-term mortality, especially of cardiovascular origin.

Complex assessment of the incidence and risk factors of delirium in a large cohort of cardiac surgery patients: a single-center 6-year experience.

BACKGROUND: Previous reports provided inconsistent data on the occurrence of postoperative delirium and emphasized its considerable impact on outcome. This study sought to evaluate the incidence and predictors of delirium, together with its relation to cerebral ischemia in a large cohort of cardiac surgery patients in a tertiary high-volume center. METHODS AND RESULTS: Consecutive patients (n = 8792) were prospectively enrolled from 2003 to 2008. Exclusion criteria were history of psychiatric disorders, use of psychoactive drugs, alcohol abuse, and data incompleteness. Finally, 5781 patients were analyzed in terms of 100 perioperative patient-specific and treatment variables. The incidence of postoperative delirium (DSM IV criteria) was 4.1% and it coexisted with cerebral ischemia in 1.1% of patients. In bivariate analysis, 49 variables were significantly linked to postoperative delirium. Multivariate analysis confirmed that delirium was independently associated with postoperative stroke (logistic odds ratio (logOR) = 2.862, P = 0.004), any blood transfusions (logOR = 4.178, P < 0.0001), age > 65 years (logOR = 2.417, P = 0.002), carotid artery stenosis (logOR = 2.15, P = 0.01), urgent/emergent surgery (logOR = 1.982, P = 0.02), fasting glucose level, intraoperative oxygen partial pressure fluctuations, and hematocrit. Area under ROC curve for the model was 0.8933. CONCLUSIONS: Early identification of nonpsychiatric perioperative determinants of delirium facilitates its diagnosis and might help develop preventive strategies to improve long-term outcome after cardiac surgery procedures.