Evaluating the Resilience of ICU Nurse Staffing Standard Operating Procedures Under Demand Variability: A Discrete...

Area of Science:

• Healthcare Operations Research
• Nursing Administration
• Patient Safety

Background:

• Standard Operating Procedures (SOPs) for ICU nurse staffing lack quantitative evaluation regarding demand variability and workforce disruption.
• Existing SOPs for nurse-to-patient assignment and escalation rules need assessment for real-world robustness.

Purpose of the Study:

• To quantitatively evaluate the robustness of different ICU nurse staffing SOPs under various demand and workforce disruption scenarios.
• To compare the performance of Fixed Ratio, Acuity-Adjusted, and Dynamic Escalation SOPs.

Main Methods:

• A Discrete Event Simulation model of a 20-bed ICU was developed and parameterized using MIMIC-IV data (20,419 MICU stays).
• Three SOPs were tested across four scenarios: baseline, census surge, nurse shortage, and combined disruption, with 100 replications each.
• Statistical analysis included Kruskal-Wallis and Dunn's post hoc tests.

Main Results:

• Dynamic Escalation showed the lowest adverse event rate (4.25/100 patient days) at baseline, outperforming Fixed Ratio (5.11/100 patient days).
• When total nurse hours were equalized across protocols, Dynamic Escalation performed significantly worse (p < 0.0001) than static protocols.
• The primary advantage of Dynamic Escalation was linked to higher staffing capacity, not superior allocation logic.

Conclusions:

• Observed differences in ICU staffing SOP performance are primarily driven by the total number of available nurse hours.
• Enhancing ICU patient safety may depend more on increasing staffing capacity than on refining specific allocation rules.
• Investment in overall staffing levels is a critical factor for improving ICU patient safety outcomes.