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Simulation-based optimization to improve hospital patient assignment to physicians and clinical units

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Abstract

A fundamental activity in hospital operations is patient assignment, which we define as the process of assigning hospital patients to specific physician services and clinical units based on their diagnosis. When the preferred assignment is not possible, typically due to capacity limits, hospitals often allow for overflow, which is the assignment of patients to other services and/or units. Overflow accelerates assignment, but can also reduce care quality and increase length of stay. This paper develops a discrete-event simulation model to evaluate different assignment strategies. Using a simulation-based optimization approach, we evaluate and heuristically optimize these strategies accounting for expected hospital and physician profit, care quality and patient waiting time. We apply the model using data from the University of Chicago Medical Center. We find that the strategies that use heuristically optimized designation of overflow services and units increase expected profit relative to the capacity-based strategy in which overflow patients are assigned to a service and unit with the most available capacity. We also find further improvement in the strategy that uses heuristically optimized overflow services and units as well as a holding unit that holds patients until a bed in their primary or secondary unit becomes available. Additionally, we demonstrate the effects of these strategies on other performance measures such as patient concentration, waiting time, and outcomes.

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Acknowledgements

The authors gratefully acknowledge the financial support from the University of Chicago Medical Center and Becker Friedman Institute Health Economics Initiative. The authors also thank the University of Chicago Medical Center and the University of Chicago Biological Sciences Division Center for Research Informatics for providing data and for discussing our model design, especially Julie Johnson, Vikas Ghayal, and George Einhorn.

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Authors and Affiliations

  1. The Center for Health and the Social Sciences, University of Chicago, Chicago, IL, 60637, USA

    Hui Zhang, Thomas J. Best & David O. Meltzer

  2. Department of Health Informatics and Administration, University of Wisconsin, Milwaukee, Milwaukee, WI, 53211-2906, USA

    Thomas J. Best

  3. Department of Medicine, University of Chicago, Chicago, IL, 60637, USA

    Anton Chivu & David O. Meltzer

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  1. Hui Zhang
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Correspondence to Hui Zhang.

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Appendix

Appendix

Table 11 The daily HM patient admissions
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Table 12 Patient LOS statistics compared with exponential distribution
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Zhang, H., Best, T.J., Chivu, A. et al. Simulation-based optimization to improve hospital patient assignment to physicians and clinical units. Health Care Manag Sci 23, 117–141 (2020). https://doi.org/10.1007/s10729-019-09483-3

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