Abstract
In this paper we develop a simulation model to study bed occupancy levels in an Intensive Care Unit (ICU). The main contributions of this study are: (1) A proposal for generalized regression models to fully capture the high variability of patients’ length of stay; (2) Proof that a simulation model that does not incorporate the management decisions by clinical staff cannot be considered valid; (3) The development of a mathematical model to represent these management decisions, and (4) A proposal for a method combining optimization with simulation to estimate the model parameters.
This provides a valid simulation model that includes the physician management of an ICU. Validation is accomplished by comparing distribution patterns in daily bed occupancy records against simulated bed occupancy data.
The methodology is tested using data provided by the Hospital of Navarre in Spain.
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Acknowledgements
The authors thank the managers and staff of the ICU of the Hospital of Navarre for providing the data and for their help in increasing our understanding of ICU performance. Part of this work was done during the stay of the Author Fermin Mallor in the Missouri University of Science and Technology, who is grateful to the Ministerio de Educación Español for the grant PR2010-0430 of the “Salvador de Madariaga” program.
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Mallor, F., Azcárate, C. Combining optimization with simulation to obtain credible models for intensive care units. Ann Oper Res 221, 255–271 (2014). https://doi.org/10.1007/s10479-011-1035-8
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DOI: https://doi.org/10.1007/s10479-011-1035-8