Antipsychotic use and diagnosis of delirium in the intensive care unit
1 College of Pharmacy and Health Sciences, Texas Southern University, Suite # 2-25G, 2450 Holcombe Blvd, Houston, TX 77004, USA
2 The Methodist Hospital, 6565 Fannin St, DB1-09, Houston, TX 77030, USA
3 New York University Langone Medical Center, 550 First Avenue, New Bellevue 15 East 9, New York, NY 10016, USA
4 Surgical Intensive Care Unit, The Methodist Hospital, Department of Surgery, 6550 Fannin St., SM 1661A, Houston, TX 77030, USA
5 Department of Surgery, Weill Cornell Medical College, 1300 York Avenue, New York, NY 10065, USA
Critical Care 2012, 16:R84 doi:10.1186/cc11342Published: 16 May 2012
Delirium is an independent risk factor for prolonged hospital length of stay (LOS) and increased mortality. Several antipsychotics have been studied for the treatment of intensive care unit (ICU) delirium that has led to a high variability in prescribing patterns for these medications. We hypothesize that in clinical practice the documentation of delirium is lower than the incidence of delirium reported in prospective clinical trials. The objective of this study was to document the incidence of delirium diagnosed in ICU patients and to describe the utilization of antipsychotics in the ICU.
This was a retrospective, observational, cohort study conducted at 71 United States academic medical centers that reported data to the University Health System Consortium Clinical Database/Resource Manager. It included all patients 18 years of age and older admitted to the hospital between 1 January 2010 and 30 June 2010 with at least one day in the ICU.
Delirium was diagnosed in 6% (10,034 of 164,996) of hospitalizations with an ICU admission. Antipsychotics were administered to 11% (17,764 of 164,996) of patients. Of the antipsychotics studied, the most frequently used were haloperidol (62%; n = 10,958) and quetiapine (31%; n = 5,448). Delirium was associated with increased ICU LOS (5 vs. 3 days, P < 0.001) and hospital LOS (11 vs. 6 days, P < 0.001), but not in-hospital mortality (8% vs. 9%, P = 0.419). Antipsychotic exposure was associated with increased ICU LOS (8 vs. 3 days, P < 0.001), hospital LOS (14 vs. 5 days, P < 0.001) and mortality (12% vs. 8%, P < 0.001). Of patients with antipsychotic exposure in the ICU, absence of a documented mental disorder (32%, n = 5,760) was associated with increased ICU LOS (9 vs. 7 days, P < 0.001), hospital LOS (16 vs. 13 days, P < 0.001) and in-hospital mortality (19% vs. 9%, P < 0.001) compared to patients with a documented mental disorder (68%, n = 12,004).
The incidence of documented delirium in ICU patients is lower than that documented in previous prospective studies with active screening. Antipsychotics are administered to 1 in every 10 ICU patients. When administration occurs in the absence of a documented mental disorder, antipsychotic use is associated with an even higher ICU and hospital LOS, as well as in-hospital mortality.