NCT07062770

Assessment of Circuit Rebreathing During CPAP Therapy

Assessment of Circuit Rebreathing During Continuous Positive Airway Pressure (CPAP) Therapy

• Status: Recruiting
• Phase: N/A
• Study type: Interventional
• Enrollment: 13 (estimated)
• Sponsor: Brigham and Women's Hospital · Academic / Other
• Sex: All
• Age: 21 Years – 70 Years
• Healthy volunteers: Not accepted

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).

Detailed 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 * 5D: 13 L/s exhaust flow with 5 cmH₂O PAP * 5E: 8 L/s exhaust flow with 5 cmH₂O PAP * 0P: 35 L/s exhaust flow with 0 cmH₂O PAP * 10A: 35 L/s exhaust flow with 10 cmH₂O PAP * 10B: 23 L/s exhaust flow with 10 cmH₂O PAP * 10C: 18 L/s exhaust flow with 10 cmH₂O PAP * 10D: 13 L/s exhaust flow with 10 cmH₂O PAP * 10E: 8 L/s exhaust flow with 10 cmH₂O PAP Primary endpoint is to evaluate the effect of exhaust flow on flow-adjusted average inspired oxygen fraction (FiO₂) during (1) wakefulness and (2) sleep between 5B vs. 5D.

Conditions

• Obstructive Sleep Apnea (OSA)

Interventions

Type	Name	Description
DEVICE	Continuous positive airway pressure (CPAP)	Subjects will be administered either 0, 5 or 10 cmH2O
OTHER	Mask exhaust port flow	Subjects will be administered varying levels of exhaust flow: 35, 23, 18, 13 and 8 L/s

Timeline

• Start date: 2025-05-27
• Primary completion: 2025-12-01
• Completion: 2025-12-01
• First posted: 2025-07-14
• Last updated: 2025-07-14

Locations

1 site across 1 country: United States

Regulatory

• FDA-regulated device study