ICU Room Design and presence of windows may impact Delirium Rates, finds study
The ICU room environment, especially the availability or absence of windows, influenced the risk of delirium among critically ill patients according to a study published in the Critical Care Medicine journal. Delirium is a common and severe complication in the ICU setting and has been hypothesized for a long time to be sensitive to natural light exposure through environmental factors. This study was conducted by Diana C. A. and colleagues.
This study evaluated the data of 3,527 patient encounters between January 2020 and September 2023, dividing patients into window-present or window-absent groups according to their rooms in the ICU. The study indicated that patients in rooms with windows are at higher risk of developing delirium, which seems to contradict the notion that natural light diminishes the risk for ICU patients.
This was a single-institution retrospective cohort study. The ICU admissions were evaluated for patients between January 2020 and September 2023. Two groups of room types were differentiated:
Windowed rooms
Nonwindowed rooms
Delirium was evaluated using the Confusion Assessment Method for the ICU (CAM-ICU). The main outcome was to assess whether delirium occurred at all during the stay in the ICU. Secondary outcomes were delirium during the first 7 days, hospital length of stay, ICU length of stay, in-hospital mortality, pain scores, and Richmond Agitation-Sedation Scale (RASS) scores. In total, 3,527 patient encounters were followed; 1,292 patients (37 percent) had been admitted to nonwindowed rooms.
Results
• Primary Outcome: Incidence of Delirium
• Delirium occurred in 21% of patients in windowed rooms (460/2,235) and 16% in nonwindowed rooms (206/1,292).
• Patients in windowed rooms had a 29% increased odds of delirium (odds ratio: 1.29; 95% CI: 1.07-1.56; p = 0.008).
• Secondary Outcomes
Hospital Stay Length :
• Patients in rooms with windows spent a little more time in the ICU (adjusted hazard ratio [aHR]: 0.93; 95% CI: 0.87-1.00) and hospital (aHR: 0.94; 95% CI: 0.87-1.00), but these findings were not statistically significant (p = 0.05 and 0.06, respectively).
Other Outcomes:
• In-hospital mortality, pain scores, and RASS scores did not differ between groups.
The study found that patients in windowed rooms were at a higher risk of delirium than those in nonwindowed rooms. These findings indicate the need for a more sensitive approach to ICU design, incorporating evidence-based strategies to optimize patient outcomes while minimizing risks. Future research should investigate other environmental factors that contribute to delirium to better inform ICU construction and patient care practices.
Reference:
Anderson DC, Warner PE, Smith MR, Albanese ML, Mueller AL, Messervy J, Renne BC, Smith SJ. Windows in the ICU and Postoperative Delirium: A Retrospective Cohort Study. Crit Care Med. 2025 Jan 13. doi: 10.1097/CCM.0000000000006557. Epub ahead of print. PMID: 39791968.
