Incidence, risk factors and consequences of ICU delirium.
OBJECTIVE
Delirium in the critically ill is reported in 11-80% of patients. We estimated the incidence of delirium using a validated scale in a large cohort of ICU patients and determined the associated risk factors and outcomes.


METHODS
Prospective study in a 16-bed medical-surgical intensive care unit (ICU).


METHODS
820 consecutive patients admitted to ICU for more than 24 h.


METHODS
Tools used were: the Intensive Care Delirium Screening Checklist for delirium, Richmond Agitation and Sedation Scale for sedation, and Numerical Rating Scale for pain. Risk factors were evaluated with univariate and multivariate analysis, and factors influencing mortality were determined using Cox regression.


RESULTS
Delirium occurred in 31.8% of 764 patients. Risk of delirium was independently associated with a history of hypertension (OR 1.88, 95% CI 1.3-2.6), alcoholism (2.03, 1.2-3.2), and severity of illness (1.25, 1.03-1.07 per 5-point increment in APACHE II score) but not with age or corticosteroid use. Sedatives and analgesics increased the risk of delirium when used to induce coma (OR 3.2, 95% CI 1.5-6.8), and not otherwise. Delirium was linked to longer ICU stay (11.5+/-11.5 vs. 4.4+/-3.9 days), longer hospital stay (18.2+/-15.7 vs. 13.2+/-19.4 days), higher ICU mortality (19.7% vs. 10.3%), and higher hospital mortality (26.7% vs. 21.4%).


CONCLUSIONS
Delirium is associated with a history of hypertension and alcoholism, higher APACHE II score, and with clinical effects of sedative and analgesic drugs.
Ouimet
Sébastien
S
Department of Medicine, University of Montreal, Montreal, Canada.
Kavanagh
Brian P
BP
Gottfried
Stewart B
SB
Skrobik
Yoanna
Y
D003693:Delirium / Q000453:epidemiology*; D005260:Female; D006801:Humans; D015994:Incidence; D007362:Intensive Care Units; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012307:Risk Factors