Augmenting blood oxygen saturation via the sleep environment: a crossover trial of non-invasive indoor oxygen diffusion.

INTRODUCTION

Continuous Positive Airway Pressure (CPAP) is the standard treatment for Obstructive Sleep Apnea (OSA); however, patient adherence is often low. This study investigated the efficacy of a novel, non-invasive environmental strategy, elevating indoor oxygen (O2) levels, as a complementary approach for individuals at potential risk of OSA.

METHODS

A crossover trial with 20 participants was conducted, each undergoing two overnight polysomnography (PSG) tests: a sham control and an intervention night. During the intervention, the point-source oxygen diffusion system (80% purity, 8 L/min) increased the indoor O2 concentration. Indoor air quality (IAQ) parameters, including O2 and carbon dioxide (CO2) levels, along with standard PSG and blood oxygen saturation (SpO2) data, were simultaneously monitored.

RESULTS

The intervention significantly increased the indoor O2 by a median of 1.4% (p < 0.001). This change demonstrated a strong positive correlation (r = 0.76, p < 0.01) with the SpO2. Multivariate regression analysis further confirmed that a 1% increase in indoor O2 predicted a 0.5% increase in nocturnal SpO2 after controlling for age, sex, body mass index (BMI), and baseline OSA severity.

CONCLUSION

These findings suggest that a moderate increase in indoor environmental oxygen can significantly improve nocturnal blood-oxygen saturation. This simple, non-invasive method may complement existing therapies, offering benefits to individuals with mild-to-moderate OSA, sleep disturbances at high altitudes, and nocturnal hypoxemia from chronic respiratory diseases such as COPD.