How many intensive care beds are enough?

Rapid changes in technology have forced many hospitals to consider changes in the size of their ICUs. One method of predicting intensive care bed needs creates a mathematical model of the unit which simulates the unit's operation. This report describes a model that provided information to a physician group charge with deciding how many beds to include in a proposed expansion of one hospital's ICU. As the total number of beds in the simulated unit increased from 7 to 15, the model predicted a linear increase in the number of empty beds and a nonlinear decrease in the number of prematurely discharged patients. Based on the results, the group chose to leave the unit's size unchanged at 11 beds. The immediate result was to facilitate planning by providing quantitative estimates of the consequences of different choices. The long-term result was an ICU whose size accommodated patient needs despite changing demand for services.