Figure 2From: Prolonged mechanical ventilation in critically ill patients: epidemiology, outcomes and modelling the potential cost consequences of establishing a regional weaning unitModelling bed occupancy and admission refusal rates for four weaning units (A to D) with differing bed capacities. A refused admission occurs when a patient is eligible for transfer from ICU to the weaning unit, but the weaning unit is full. *The broken lines represent the effect of unstable patients being transferred out of the weaning unit back to the ICU.Back to article page