A ventilator (20) including a pneumatic system (22) for providing and receiving breathing gas, and a controller (50) operatively coupled with the pneumatic system (22). The controller is operable to control circulation by the pneumatic system of breathing gas to and from a patient (24), and to adjust (522) at least one of a volume and pressure of breathing gas delivered to the patient (24), such adjustment being based upon elastic properties of a component used to fluidly couple the pneumatic system (22) to a patient (24).
