Modelling and simulation of an outpatient surgery unit

In this paper we propose a new approach to design and control an ambulatory surgery unit through formal modelling and discrete-event simulation. Taking into account the demand increase for ambulatory care in the hospital, we propose a comprehensive methodology to adjust the required resources (beds and stretchers) to optimize patient pathway through the ambulatory surgery unit. Several performance indicators are considered such as patient length of stay (late discharge evaluation) and patient waiting time to determine the optimal number of patients and types of surgeries to be performed each day. Resource sizing is also proposed to optimize patient rotation between the ambulatory unit and the operating theater. Along with quantitative results, a risk analysis is also proposed to help decision makers with the implementation of the new organization.