JMIR Publications

ABSTRACT

Background:

Hospital falls are a persistent and significant threat to patient safety globally. Caregiver visibility and proactive patient monitoring are recognized as crucial extrinsic factors in mitigating fall risk within hospital environments.

Objective:

This study aimed to investigate the association between the percentage of spatial shadow zone, defined as areas within an acute care unit unvisited by mobile workstations for prolonged periods, and the incidence of hospital falls and intensive care unit (ICU) transfers.

Methods:

This retrospective observational study was conducted in a 400 square meter acute care unit of a tertiary hospital over 210 days. An Ultra-Wideband Real-Time Location System (RTLS) was deployed to continuously track mobile workstations spatial coverage. Spatial shadow zones were defined as areas unvisited by mobile workstations for 60 continuous minutes. The primary outcome was hospital falls; the secondary outcome was ICU transfer. Multivariable logistic regression analysis, adjusted for hour of day and day of week, was used to examine the association between the percentage of spatial shadow zone and these outcomes. Sensitivity analyses were performed by varying the spatial dilation distance (1-4 meters) and temporal shadow zone thresholds (15-90 minutes).

Results:

During the study period, 8 hospital falls and 89 ICU transfers occurred. RTLS validation indicated a mean positional error of 0.346 meters. In multivariable regression, a higher percentage of spatial shadow zone was significantly associated with an increased odds of hospital falls (Odds Ratio = 1.03, 95% CI [1.02, 1.05], p <.001). Conversely, a higher percentage of spatial shadow zone was associated with a decreased odds of ICU transfer (Odds Ratio = 0.99, 95% CI [0.99, 0.99], p <.001). Sensitivity analyses demonstrated consistence of the association between spatial shadow zones and falls across varying parameter settings.

Conclusions:

This study provides novel evidence for a significant positive association between percentage of spatial shadow zones and hospital falls, underscoring the critical role of caregiver visibility in fall prevention. The findings suggest that proactively minimizing spatial shadow zones through optimized hospital design, workflow strategies, and technology-enabled monitoring may be a valuable approach to enhance patient safety and reduce hospital falls in acute care settings. Further interventional research is warranted to directly test strategies for reducing spatial shadow zones and their impact on patient outcomes.