The Immediate Effects of Overnight Continuous Positive Airway Pressure Ventilation Using Short Time Multiscale Entropy Method

• Main Authors: Hong-Ruei Chen, 陳鴻睿
• Other Authors: Hsien-Tsai Wu
• Format: Others
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/31437274386059030448

碩士 === 國立東華大學 === 電機工程學系 === 101 === Continuous positive airway pressure (CPAP) is a standard hospital treatment for patients with obstructive sleep apnea (OSA). Previous research has proven that long-term and regular provision of CPAP treatment can reduce the incidence of cardiovascular diseases, and improve vascular health and autonomic nerve function in patients with OSA. However, few studies have considered the effects of short-term CPAP treatment on patients. This study used a self-made air pressure sensing system (APSS) as a signal acquisition platform, and collected data on patients with moderate to severe OSA who were undergoing polysomnography (PSG) or CPAP titration treatment at the Kaohsiung Chang Gung Memorial Hospital Sleep Center. A total of 35 patients with moderate to severe OSA who had never received relevant treatment participated in this study. These patients were divided into Group 1, comprising 22 patients receiving a PSG exam for the first time, and Group 2, comprising 13 patients undergoing CPAP titration for the first time. A 5-minute stable pulse signal was obtained from each patient before and after PSG or CPAP titration, with the patient awake and in a supine position. The pulse-pulse interval (PPI) of the signal was obtained, and three indicators of frequency-domain heart rate variability (HRV) were employed to evaluate autonomic nerve function before and after the experiment. In addition, a multiscale entropy (MSE) algorithm, which is used to evaluate physiological signal complexity, was modified to short time MSE (sMSE), which is more appropriate for short-term signal length computations. The sMSE was employed to rapidly evaluate the change in overall health status of the patients before and after the experiment. The experimental results indicated that the patients in Group 1 showed significant increases in sympathetic nerve activity after the experiment. Their LF/HF values, which represent balance in autonomic nerve activity, also exhibited significant increases. However, the sMSE1 physiological signal complexity indicator showed a significant decrease. By contrast, the LF/HF value of the autonomic nerve activity in Group 2 patients did not show significant changes before and after the experiment. Nevertheless, the sMSE1, sMSE2, and sMSE3 indicators for Group 2 patients showed a significant increase. In summary, this study adopted frequency-domain HRV indicators and the sMSE indicator (which reflects the overall health status) to observe enhancements in the autonomic nerve function and overall health status of patients receiving short-term CPAP treatment. The results elucidated the immediate therapeutic effects and health benefits of CPAP, and can be used to facilitate improving the willingness of patients to undergo CPAP treatment.