Abstract
Sleep apnea syndrome (SAS) is a sleep-disordered breathing that causes hypoxemia during sleep. The effect of SAS on patients with heart failure attracts increasing attention. As a treatment for the sleep-disordered breathing, continuous positive airway pressure (CPAP) treatment is widely used and effective even for heart failure patients. However it cannot prevent the decrease of oxygen saturation enough because the oxygen flow is usually kept at a constant rate. In this paper, the oxygen saturation dynamics under the CPAP treatment is modeled to explore the method of maintaining oxygen saturation level of heart failure patients with SAS. Assuming that the oxygen saturation dynamics in apnea and in eupnea can be represented by different models, the model parameters were identified from the data in apnea and that in eupnea respectively by the least square method. Simulation results demonstrated the validity of the obtained models.
