Health Care Management Science

, Volume 22, Issue 2, pp 287–303 | Cite as

A proactive transfer policy for critical patient flow management

  • Jaime GonzálezEmail author
  • Juan-Carlos Ferrer
  • Alejandro Cataldo
  • Luis Rojas


Hospital emergency departments are often overcrowded, resulting in long wait times and a public perception of poor attention. Delays in transferring patients needing further treatment increases emergency department congestion, has negative impacts on their health and may increase their mortality rates. A model built around a Markov decision process is proposed to improve the efficiency of patient flows between the emergency department and other hospital units. With each day divided into time periods, the formulation estimates bed demand for the next period as the basis for determining a proactive rather than reactive transfer decision policy. Due to the high dimensionality of the optimization problem involved, an approximate dynamic programming approach is used to derive an approximation of the optimal decision policy, which indicates that a certain number of beds should be kept free in the different units as a function of the next period demand estimate. Testing the model on two instances of different sizes demonstrates that the optimal number of patient transfers between units changes when the emergency patient arrival rate for transfer to other units changes at a single unit, but remains stable if the change is proportionally the same for all units. In a simulation using real data for a hospital in Chile, significant improvements are achieved by the model in key emergency department performance indicators such as patient wait times (reduction higher than 50%), patient capacity (21% increase) and queue abandonment (from 7% down to less than 1%).


Markov decision process Approximate dynamic programming Emergency department Critical care beds Patient flow 



The authors thank their colleagues and students for helpful discussions and feedback at various stages of this research project. The authors also thank the three anonymous referees and the editor for helpful comments on earlier versions of this paper. Finally, the authors would like to thank for the financial support provided by FONDEF (Chile) grant no. CA13I10319.


This study was funded by FONDEF (grant number CA13I10319).

Compliance with Ethical Standards

Conflict of interests

The authors declare that they have no conflict of interest.


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© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  1. 1.School of EngineeringPontificia Universidad Católica de ChileMaculChile
  2. 2.School of MedicinePontificia Universidad Católica de ChileSantiagoChile

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