Closed-loop kinesthetic stimulation for the treatment of sleep apnea syndromes

Sleep apnea syndrome (SAS) is a common disease characterized by recurrent episodes of breathing pauses or important reductions in respiratory amplitude during patient's sleep. These episodes provoke significant cardiorespiratory modifications that may have long-term cardiovascular consequences. This paper proposes a novel approach for the treatment of SAS, based on a closed-loop kinesthetic stimulation, adapted as a function of the patient's physiological response. The closed-loop control system is based on concurrent, coupled proportionalderivative (PD) controllers that modulate the stimulation amplitude delivered to the patient. The controller was tested on a first phase of a clinical protocol including 12 patients with previously diagnosed SAS. Results from one patient are presented in this paper, showing how the proposed controller is capable to adapt stimulation parameters, converging to a minimum patient-specific amplitude. These results are encouraging regarding the feasibility of the integration of the proposed controller into the therapy for the adaptive optimization of the kinesthetic stimulation amplitude and warrant a second phase of the clinical study of this system.