VENTILATOR CIRCUIT MODEL FOR OPTIMIZATION OF HIGH-FREQUENCY OSCILLATORY VENTILATION

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Ventilators for high-frequency oscillatory ventilation (HFOV), Sensormedics 3100, were not designed to tolerate spontaneous breathing of a patient. An experimental Demand Flow System (DFS) is being developed to support spontaneous breathing during HFOV. A control system of the DFS requires a model of the ventilator circuit of Sensormedics 3100. A new model of the circuit was designed, including the oscillating membrane, the inspiratory and expiratory branches of the circuit, the expiratory valve, and a spontaneously breathing patient. The model was implemented in the Multisim software environment. A bench test suggests that the model predicts the basic changes in pressure within the ventilator circuit and that its modified version can be used in the DFS control algorithm.

Keywords:
high-frequency oscillatory ventilation (HFOV), ventilator circuit, lumped-parameter model, electro-acoustic analogy

Autoři: Jan Matějka; Jakub Ráfl; Michal Čech; Martin Rožánek
Působiště autorů: Czech Technical University in Prague, Faculty of Biomedical Engineering, Kladno, Czech Republic
Vyšlo v časopise: Lékař a technika - Clinician and Technology No. 2, 2012, 42, 61-64
Kategorie: Conference YBERC 2012

Souhrn

Keywords:
high-frequency oscillatory ventilation (HFOV), ventilator circuit, lumped-parameter model, electro-acoustic analogy

Zdroje

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