ICU Architectural Design Affects the Delirium Prevalence: A Comparison Between Single-Bed and Multibed Rooms

Objectives: Delirium risk factors are related to the patients' acute and chronic clinical condition, treatment, and environment. The environmental risk factors are essentially determined by the ICU architectural design. Although there are countless architectural variations among the ICUs, all can be classified as single-or multibed rooms. Our objectives were to compare the ICU delirium prevalence and characteristics (coma/delirium-free days, first day in delirium, and delirium motoric subtypes) of critically ill patients admitted in single-or multibed rooms. Design: Retrospective. Setting: ICU of a teaching oncologic hospital with 31 beds. Twenty-three beds distributed in one multibed room with 13 beds and other with 10 beds. Eight beds distributed in single-bed rooms. Patients: All adult patients admitted from February to November 2011. Interventions: None. Measurements and Main Results: We evaluated 1,587 patients and included 1,253 patients. Patients' characteristics at ICU admission and their outcomes along the ICU stay were not different between patients admitted in single-or multibed rooms. One hundred sixty-three patients (13.0%) had delirium, and the prevalence was significantly lower in patients admitted in single-bed rooms (6.8% x 15.1%; p < 0.01). This lower prevalence occurred in patients admitted due to a medical (11.0% x 25.6%; p < 0.01) or postoperative (5.0% x 11.4%; p < 0.01) reason. However, the coma/ delirium-free days, the first day in delirium, and the delirium motoric subtypes were not different between the single-and multibed rooms. The risk factors associated with delirium were admission in multibed rooms (odds ratio, 4.03; 95% CI, 2.13-7.62), older age, ICU-acquired infection, and higher Simplified Acute Physiology Score 3 and Sequential Organ Failure Assessment score. Conclusions: Critically ill patients admitted in single-bed rooms have a lower prevalence of delirium than those admitted in multibed rooms. However, coma/delirium-free days, first day in delirium, and motoric subtypes were not different.