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Completed Not applicable Interventional Accepts healthy volunteers Results available

Assessing Variability of the Ventilatory Response to Duffin's Rebreathing Procedure

ClinicalTrials.gov ID: NCT05168501

Public ClinicalTrials.gov record NCT05168501. Field values are reproduced from the official study page; the official ClinicalTrials.gov record remains the source of truth for eligibility, enrollment, and contact information.

ClinicalTrials.gov public records Last synced Sep 8, 2026, 6:26 AM EDT

Data is sourced from official ClinicalTrials.gov public API records. Always review the official ClinicalTrials.gov record for the latest information.

Brief summary

Reproduced verbatim from the official ClinicalTrials.gov record. Not medical advice.

This study will combine Duffin's rebreathing procedure with additional study procedures, such as quantitative pupillometry, that are planned for subsequent clinical studies in order to confirm feasibility and gather reproducibility data using the procedure. The reproducibility of Duffin rebreathing has been assessed previously by Mahamed and Duffin (2001) performing hyperoxic and hypoxic rebreathing procedures measured once daily for 14 consecutive days and then by Jensen et al. (2010) performing 4 pairs of hyperoxic and hypoxic rebreathing procedures in 1 day followed by 1 pair on 4 additional days separated by weeks to more than a month. The present study is an unblinded reproducibility assessment to assess variability of the ventilatory response to Duffin's rebreathing procedure. Subjects will report to the study site for screening between Days -28 to -2 and then will return to the site on Day -1 for baseline assessments and check-in. After check-in (Day -1), subjects will remain in study site for PD assessments on Day 1 and check out on Day 2. Paired rebreathing procedures (i.e., at two different isoxic end tidal PO2 \[partial pressure oxygen\] levels) will be performed on Day 1 at 0, 2, 4, and 6 hours. An additional pair of rebreathing procedures will be performed on Day 2 before checkout (approximately 24 hours). Subjects will not be administered any drugs in this study.

Study identification

NCT ID
NCT05168501
Recruitment status
Completed
Study type
Interventional
Phase
Not applicable
Enrollment
7 participants

Conditions and interventions

Eligibility (public fields only)

Age range
18 Years to 50 Years
Sex
All
Healthy volunteers
Accepts healthy volunteers

This page does not interpret eligibility. Detailed inclusion and exclusion criteria are on the official ClinicalTrials.gov record.

Study timeline

Start date
Dec 26, 2021
Primary completion
Feb 17, 2022
Completion
Feb 17, 2022
Last update posted
Jul 14, 2024

2021 – 2022

United States locations

U.S. sites
1
U.S. states
1
U.S. cities
1
Facility City State ZIP Site status
Spaulding Clinical Research West Bend Wisconsin 53095

Site contact phone numbers, emails, and investigator names are intentionally not displayed here. Open the official ClinicalTrials.gov record for site contact information.

About this trial record page

What this page shows
Public field values for ClinicalTrials.gov record NCT05168501, including study identification, conditions, interventions, eligibility (age, sex, healthy volunteer), timeline, and U.S. site list.
What this page does not do
No medical advice, eligibility judgments, treatment recommendations, study quality scoring, or AI-generated medical summaries. No site contact phone numbers, emails, or investigator names.
Where the data comes from
Sourced from the official ClinicalTrials.gov public API. The official record is the source of truth.
Last refresh
Last update posted Jul 14, 2024 · Synced Sep 8, 2026

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Open the official record

The complete protocol, eligibility criteria, and contact information for NCT05168501 live on ClinicalTrials.gov.

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