Intermittent Hypoxia-initiated Plasticity in Humans: A Multi-pronged Therapeutic Approach to Treat Sleep Apnea and Overlapping Co-morbidities

The MIH protocol will be comprised of a 20-minute baseline period followed by exposure to twelve two-minute episodes of hypoxia \[partial pressure of end-tidal oxygen (PETO2)= 50 mmHg\]. Each episode will be interspersed with a 2-minute recovery period under normoxic conditions. The final episode will be followed by a 30-minute end-recovery period. The partial pressure of end-tidal carbon dioxide (PETCO2) will be sustained 2 mmHg above baseline values for the last ten minutes of baseline and throughout the remainder of the protocol. To rapidly induce a PETO2 of 50 mmHg participants will inspire a gas mixture comprised of 8 % oxygen and 92 % nitrogen from a non-diffusible bag. To maintain PETO2 (i.e. 50 mmHg) and PETCO2 (i.e. 2 mmHg above baseline) at the desired levels supplemental oxygen and carbon dioxide will be added to the inspiratory line from the output of a flow meter device that receives inputs from tanks of 100 % oxygen and 100 % carbon dioxide.

"During sham MIH the participants will be exposed to compressed air (the equivalent of room air)."