Heart disease is the leading cause of death in the United States. The length of stay (LOS) is a well-established parameter used to evaluate health outcomes among critically ill patients with heart disease in cardiac intensive care units (CICUs). While evidence suggests that the presence of daylight and window views can positively influence patients’ LOS, no studies to date have differentiated the impact of daylight from window views on heart disease patients. Also, existing research studies on the impact of daylight and window views have failed to account for key clinical and demographic variables that can impact the benefit of such interventions in CICUs.

This retrospective study investigated the impact of access to daylight vs. window views on CICU patients' LOS. The study CICU is located in a hospital in the southeast United States and has rooms of the same size with different types of access to daylight and window views, including rooms with daylight and window views (with the patient bed located parallel to full-height, south-facing windows), rooms with daylight and no window views (with the patient bed located perpendicular to the windows), and windowless rooms. Data from electronic health records (EHRs) for the time-period September 2015 to September 2019 (n=2936) were analyzed to investigate the impact of room type on patients’ CICU LOS. Linear regression models were developed for the outcome of interest, controlling for potential confounding variables.

Ultimately, 2319 patients were finally included in the study analysis. Findings indicated that patients receiving mechanical ventilation in rooms with access to daylight and window views had shorter LOS durations (16.8 h) than those in windowless rooms. Sensitivity analysis for a subset of patients with LOS ≤3 days revealed that parallel bed placement to the windows and providing access to both daylight and window views significantly reduced their LOS compared to windowless rooms in the unit (P=0.007). Also, parallel bed placement to the window significantly reduced LOS in this patient subset for those with an experience of delirium (P=0.019), dementia (P=0.008), anxiety history (P=0.009), obesity (P=0.003), and those receiving palliative care (P=0.006) or mechanical ventilation (P=0.033).

Findings from this study could help architects make design decisions and determine optimal CICU room layouts. Identifying the patients who benefit most from direct access to daylight and window views may also help CICU stakeholders with patient assignments and hospital training programs.