Control of a blower-based lung simulator for testing of mechanical ventilators

Automated functions are becoming increasingly important in mechanical ventilation, which react to patient behavior during ventilation and improve lung-and diaphragm protective ventilation therapy largely independent of the operator's experience. These functions must be extensively tested for a wide range of parameter combinations representing the lung mechanics to ensure patient safety. Therefore, this paper presents a first approach of an experimental setup with an underlying control concept for a lung simulator without volume limitation, which is capable of reproducing simulated patient behavior in the form of the occurring airflow and airway pressure at the system's interface. The general design of the lung simulator setup is based on the work of F. Bautsch et al. [1] and is modified slightly with regard to the underlying control concept. To illustrate this concept, a single-compartment model is used to simulate the virtual patient behavior. The lung model calculates the reference airflow of the patient that will occur due to the induced pressure difference created by the virtual patient or through a device under test at the system's interface representing the conditions at the airways of the virtual patient. The first experimental setup, generating breathing cycles of one virtual patient for mandatory and assisted ventilation, shows that the system can generate a realistic behavior of the simulated patient at the system's interface with regard to the desired airflow.