Abstract
Obstructive sleep apnea syndrome (OSAS) is occurred by apnea by the obstruction of upper trachea while sleeping, followed by repetitive drop on arterial oxygen saturation ($SpO_2$). Therefore, the present study was focused on relation between $SpO_2$ of while having difficulty in breathing and clinical characteristics of OSAS while sleeping. The study took place at Ewha women university Mokdong hospital with 149 subjects (male 121, female 28) who were examined for polysomnography (PSG) from May 2007 to February 2008. All subjects were adhered to electrodes and sensors to measure electroencephalogram (EEG), electrooculogram (EOG), chin & leg electromyogram (EMG), airflow at nasal and oral cavities, breathing movement of chest and abdominal snoring sound and $SpO_2$. Lowest $SpO_2$ in male was meaningfully low with higher body mass index (BMI), louder snoring sound and thick neck circumference (p<0.01). While mean $SpO_2$ based on the degree of AHI did not show significant difference, lowest $SpO_2$ was significantly low with high AHI (p<0.001). Also, lowest $SpO_2$ was closely correlated with BMI (r=-00.343, p<0.001), snoring sound (r=0.177, p<0.05), apnea index (r=-0.589, p<0.001), hypopnea index (r=-0.336, p<0.001) and apnea-hypopnea index (r=-0.664, p<0.001). $SpO_2$ was closely related to clinical characteristics of OSAS, like male, BMI, snoring sound and neck circumference. Also, polysomnography accompanied by recent development of sleep study is considered as critical test to diagnose OSAS, decide the severity of illness, and evaluate the treatment plan.