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Assessment of Circuit Rebreathing During CPAP Therapy

Not Applicable
Recruiting
Conditions
Obstructive Sleep Apnea (OSA)
Registration Number
NCT07062770
Lead Sponsor
Brigham and Women's Hospital
Brief 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.

Recruitment & Eligibility

Status
RECRUITING
Sex
All
Target Recruitment
13
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.

Study & Design

Study Type
INTERVENTIONAL
Study Design
SEQUENTIAL
Primary Outcome Measures
NameTimeMethod
Change in flow-adjusted average inspired oxygen fraction (FiO₂) during wake.through study completion, an average of 1 year

Difference in FiO2 between 23L/s vs 13L/s exhaust flow at 5 cmH2O PAP.

Change in flow-adjusted average inspired oxygen fraction (FiO₂) during sleep.through study completion, an average of 1 year

Difference in FiO2 between 23L/s vs 13L/s exhaust flow at 5 cmH2O PAP.

Secondary Outcome Measures
NameTimeMethod
Impact on hypoxic burden during sleep.through study completion, an average of 1 year

Difference in hyboxic burden between 23L/s vs 13L/s exhaust flow at 5 cmH2O PAP.

Trial Locations

Locations (1)

Brigham and Women's Hospital

🇺🇸

Boston, Massachusetts, United States

Brigham and Women's Hospital
🇺🇸Boston, Massachusetts, United States
Atqiya Aishah, PhD
Contact
857 396 3808
aaishah@bwh.harvard.edu
Scott A Sands, PhD
Contact
617 278 0911
sasands@bwh.harvard.edu

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