Assessment of Circuit Rebreathing During Continuous Positive Airway Pressure (CPAP) Therapy
Brigham and Women's Hospital
Summary
The goal of this research is to better understand how different CPAP mask designs affect airflow and rebreathing of exhaled carbon dioxide (CO₂) during sleep in individuals with obstructive sleep apnea (OSA).
Description
To understand the existence and severity of circuit rebreathing during treatment with continuous positive airway pressure (CPAP) using different sizes of the exhaust ports in individuals with obstructive sleep apnea (OSA). Flow-adjusted end-tidal oxygen (PetO2) and carbon dioxide (PetCO2) will be assessed to determine the magnitude of hypoxic load during both wakefulness and sleep. To systematically assess these conditions, the conditions were defined as follows: * 5A: 35 L/s exhaust flow with 5 cmH₂O PAP * 5B: 23 L/s exhaust flow with 5 cmH₂O PAP * 5C: 18 L/s exhaust flow with 5 cmH₂O PAP *…
Eligibility
- Age range
- 21–70 years
- Sex
- All
- Healthy volunteers
- No
Inclusion Criteria: * Moderate to severe OSA (AHI\>20) * Self-reported CPAP users or have previously used CPAP * Self-reported holding pressure of maximum 13 cmH2O (if known) * Age: 21-70 * BMI: 18-40 kg/m2 Exclusion Criteria: * Self-reported severe mouth-breathing * Requirement for nocturnal supplemental oxygen or other ventilatory support * Severe cardiovascular or pulmonary disease * Any unstable or acute medical condition * Any additional sleep disorder, including insomnia, except for OSA.
Interventions
- DeviceContinuous positive airway pressure (CPAP)
Subjects will be administered either 0, 5 or 10 cmH2O
- OtherMask exhaust port flow
Subjects will be administered varying levels of exhaust flow: 35, 23, 18, 13 and 8 L/s
Location
- Brigham and Women's HospitalBoston, Massachusetts