[Clinical value of TS90% in evaluation of hypoxemia in patients with obstructive sleep apnea/hypoventilation syndrome].

Objective: To explore the appropriate study how to properly evaluate the hypoxemia degree in patients with obstructive sleep apnea/hypoventilation syndrome (OSAHS).

Methods: polysomnography was conducted on 108 OSAHS patients and 37 simple snorers to record the minimum oxygen saturation level (MiO(2)) and the total recorded time spent below 90% oxygen saturation (TS90%). The correlation between MiO(2) and the percent of the total recorded time spent below 90% oxygen saturation (TS90%) with the AHI were calculated.

Results: The value of TS90% was significantly increased, and the value of MiO(2) was significantly decreased as the severity of OSAHS increased (all P < 0.001). The correlation coefficients of TS90% with AHI and with Epworth sleepiness scale (ESS) were both much higher than those of MiO(2).

Conclusion: TS90% can express the severity of hypoxemia of the OSAHS patients more correctly than MiO(2). TS90% combined with MiO(2) can comprehensively and objectively reflect the severity of hypoxia of the OSAHS patients.