title: Delirium is a robust predictor of morbidity and mortality among critically ill patients treated in the cardiac intensive care unit.
abstract: BACKGROUND
  Delirium is common in the medical and surgical intensive care unit (ICU), and its association with morbidity and mortality is well described. Despite emerging data, which have highlighted a growing critical care burden in the contemporary cardiac ICU (CICU), much less is known about delirium in this specialized setting.
  
  
  RESULTS
  Records for consecutive CICU patients aged ≥18 years who were admitted to our academic, tertiary care institution from December 2012 to March 2014 for a primary cardiovascular diagnosis were reviewed. Only those with a documented Confusion Assessment Method for ICU score were included in the final analysis. Baseline characteristics, resource use, and outcomes were collected. Disease severity was assessed using the modified Acute Physiology and Chronic Health Evaluation II score and the Simplified Acute Physiology ScoreII. Multivariable logistic and linear regression models were constructed to evaluate the association between CICU delirium, length of stay, and death. Among 590 patients included, the prevalence of CICU delirium was 20.3%. Delirious patients were older, had greater disease severity, required longer ICU stays (5 vs 2 days; P < .001), and had higher mortality (27% vs 3%; P < .001). In the adjusted setting, delirium remained strongly associated with both increased mortality (P < .001) and length of stay (P = .001).
  
  
  CONCLUSIONS
  In those with cardiac critical illness, delirium is common and associated with worse survival and greater resource consumption. Future study is needed to validate these findings and to develop effective strategies for the early identification and treatment of the delirious CICU patient.
authors.affiliation: Department of Internal Medicine, University of North Carolina, Chapel Hill, NC.
authors.forename: Eric
authors.initials: E
authors.lastname: Pauley
authors.affiliation: University of North Carolina Center for Heart and Vascular Care, Chapel Hill, NC.
authors.forename: Anton
authors.initials: A
authors.lastname: Lishmanov
authors.affiliation: North Carolina Memorial Hospital, University of North Carolina, Chapel Hill, NC.
authors.forename: Sara
authors.initials: S
authors.lastname: Schumann
authors.affiliation: Department of Psychiatry, University of North Carolina, Chapel Hill, NC.
authors.forename: Gary J
authors.initials: GJ
authors.lastname: Gala
authors.affiliation: Divisions of Critical Care Medicine and Cardiology, University of Alberta, Edmonton, Alberta, Canada.
authors.forename: Sean
authors.initials: S
authors.lastname: van Diepen
authors.affiliation: University of North Carolina Center for Heart and Vascular Care, Chapel Hill, NC; Divisions of Cardiology and Pulmonary/Critical Care Medicine, University of North Carolina, Chapel Hill, NC. Electronic address: katzj@med.unc.edu.
authors.forename: Jason N
authors.initials: JN
authors.lastname: Katz
mesh_terms: D018806:APACHE; D058186:Acute Kidney Injury / Q000453:epidemiology; D000367:Age Factors; D000368:Aged; D015331:Cohort Studies; D015897:Comorbidity; D016638:Critical Illness; D003693:Delirium / Q000453:epidemiology*; D005260:Female; D006323:Heart Arrest / Q000453:epidemiology / Q000401:mortality; D006331:Heart Diseases / Q000453:epidemiology / Q000401:mortality*; D006349:Heart Valve Diseases / Q000453:epidemiology / Q000401:mortality; D006801:Humans; D007362:Intensive Care Units; D007902:Length of Stay; D016014:Linear Models; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009203:Myocardial Infarction / Q000453:epidemiology / Q000401:mortality; D009657:North Carolina / Q000453:epidemiology; D015995:Prevalence; D011379:Prognosis; D012131:Respiratory Insufficiency / Q000453:epidemiology; D018805:Sepsis / Q000453:epidemiology; D012720:Severity of Illness Index