Comparative Study Between Medical/Surgical Intensive Care Units vs. Mixed Intensive Care Units in Key Performance Indicators

Background This comparative study evaluates the performance of medical/surgical and mixed intensive care units (ICUs) at a tertiary care university hospital in Riyadh, Saudi Arabia, using key performance indicators (KPIs). Since its establishment in 1982, the hospital has provided comprehensive medical services, including specialized, closed-model ICUs, including medical, surgical, and pediatric ICUs. In 2021, these ICUs transitioned to a mixed ICU model to enhance efficiency and patient care. This study aims to assess the impact of this transition on various KPIs, including mortality rate, ICU length of stay (LOS), bed occupancy rate (bOR), ICU readmission rate within 48 hours, unplanned extubation, glycemic control, and delayed ICU discharge. Methodology Data from 2018 to 2022 were analyzed, comparing the separate medical and surgical ICUs model (2018-2020) with the mixed ICU model (2021-2022). Statistical analyses were performed, including independent t-tests and analysis of variance (ANOVA), to determine significant differences between the ICU models. Results The transition to the mixed ICU model significantly improved several KPIs. The standardized mortality ratio (SMR) decreased from 0.575 in the specialized ICU model to 0.399 in the mixed ICU model, reflecting a marked improvement in patient outcomes. The average LOS also reduced from 4.989 days in the specialized ICUs to 4.481 days in the mixed ICU model. Additionally, the bOR significantly dropped from 91.00% to 72.08% (<i>P</i> = 0.000), enhancing resource efficiency. Readmission rates within 48 hours were reduced from 0.883 to 0.475 and delayed ICU discharge rates also improved, falling from 34.59% to 23.31%. Our findings revealed that the mixed ICU model outperformed the specialized ICU in most KPIs, reflecting notable enhancements in operational efficiency and patient outcomes. Conclusions The transition to a mixed ICU model led to significant improvements in KPIs, including reductions in mortality rate and average LOS, alongside enhanced bOR and lower readmission rates within 48 hours. Delayed ICU discharge rates and glycemic control also showed notable positive changes. These improvements likely stem from the interdisciplinary expertise and flexibility of the mixed ICU environment, which supports better resource allocation and patient care. The study underscores the potential of mixed ICUs to optimize both clinical outcomes and operational efficiency in hospitals. Implementing such models can serve as a robust strategy for improving ICU performance. However, further research is needed to evaluate the long-term effects and assess the applicability of this model in diverse healthcare settings to fully validate its benefits.