Respiratory Disease (Clinically Stable Individuals - Patients Recovered From Respiratory Disease)NCT07066566
The Effect of Asymmetrical vs. Symmetrical High Flow Nasal Cannula on the Work of Breathing
A study testing Asymmetric nasal cannula - DUET and Conventional nasal high flow cannula in people with Respiratory Disease (Clinically Stable Individuals - Patients Recovered From Respiratory Disease), run by Larissa University Hospital at 1 site in Greece.
Trial summary
The goal of this study randomized single-center crossover study is to evaluate the impact of asymmetrical versus symmetrical nasal high flow (NHF) therapy on work of breathing (WOB). The main question it aims to answer are: 1. Read more about this study
- Who is it for?
- Ages 18 years and olderHealthy volunteers can take part
- Conditions the study is for
- Respiratory Disease (Clinically Stable Individuals - Patients Recovered From Respiratory Disease)
- What is being tested?
- Asymmetric nasal cannula - DUET and Conventional nasal high flow cannula
- Type of treatment
- Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 30 participants
- Where
- 1 siteGreece
- Study dates
- 9 Apr 2024to 1 Sep 2025
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- age ≥18 years old
- absence of symptoms and signs of respiratory failure (SpO2>95% at FiΟ2 0.21)
Who cannot join
- pregnancy
- SpO2<94% at FiΟ2 0.21
- neuromuscular disease
- contraindications to esophageal pressure monitoring (e.g., uncontrolled coagulopathy, esophageal disease, nasal trauma, allergy to local lidocaine)
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Greece1 site, 1 recruiting
- Recruiting
University Hospital of Larissa, Department of Pulmonary Medicine
Larissa, 41222
Ioannis Dr Pantazopoulos, Associate Professor, +30 - 69445661525, pantazopoulosioannis@yahoo.com
Ioannis Dr Pantazopoulos, Associate Professor
About this study
Official title: The Effect of Asymmetrical vs. Symmetrical High Flow Nasal Cannula on the Work of Breathing: A Randomised Cross-over Study
The goal of this study randomized single-center crossover study is to evaluate the impact of asymmetrical versus symmetrical nasal high flow (NHF) therapy on work of breathing (WOB). The main question it aims to answer are:
- Does the asymmetrical NHF interface improve the work of breathing compared to the symmetrical NHF interface? Researchers will compare the symmetrical NHF interface to the symmetrical NHF interface to see if the the asymmetrical interface has a greater impact on the work of breathing.
Read more
Participants will :
- receive NHF via both interfaces (FiO₂ 0.21, 50 L/min) for 15 minutes, in random order, with esophageal pressure monitoring and bioelectrical impedance analysis performed.
- baseline characteristics will me monitored throughout the interventions
- Esophageal pressure and minute ventilation will be monitored.
Read the detailed description
Each participant will undergo all phases of the study while seated comfortably, breathing room air. Vital signs, including blood pressure, heart rate, and peripheral oxygen saturation (%SpO₂), will be continuously monitored and recorded throughout.
Respiratory mechanics will be assessed using esophageal pressure (Pes) monitoring. A thin latex balloon catheter (10 cm long, 3-5 cm circumference; Cooper surgical, USA), filled with 0.5 mL of air, will be placed in the mid-esophagus (~45 cm from the nares) and will be connected to a pressure transducer (RSS-100HR, Hans Rudolph Inc., USA). Correct positioning will be confirmed by observing equal fluctuations in Pes and airway pressure (Paw) during occluded breaths. Balloon integrity will be verified before, after, and as needed during the procedure.
Participants will be instructed to breathe quietly on room air (FiO₂ 0.21) to allow for baseline assessment. Volume will be recorded using a heated pneumotachometer (Series 3813; Hans Rudolph Inc., USA) and the Research Pneumotach System (RSS100-HR), sampling at 50 Hz, a sampling rate exceeding the Nyquist criterion for respiratory signals. A bioelectrical impedance technology device (ExSpiron, Respiratory Motion Inc., Waltham, MA) will then be attached around the chest to assess lung volume changes.
Participants will then be randomized in a 1:1 ratio to one of two intervention sequences using a computer-generated randomization schedule.
- Sequence 1: Symmetrical NHF Interface - 3-minute washout period - Asymmetrical NHF Interface
- Sequence 2: Asymmetrical NHF Interface - 3-minute washout period - Symmetrical NHF Interface In the seated position, participants will both 15-minute phases, separated by a 3-minute washout period to prevent residual effects. During the "Symmetrical Interface" phase, participants will breathe using the conventional symmetrical NHF cannula, and during the asymmetrical phase, the asymmetrical interface (DUET, Fisher and Paykel Healthcare, Auckland, New Zealand) will be used. High-flow oxygen will be delivered using a commercial system (AIRVO 3; Fisher and Paykel Healthcare, Auckland, New Zealand) set at a flow of 50 L/min, temperature of 37°C, and FiO₂ of 0.21.
- Conditions
- Respiratory Disease (Clinically Stable Individuals - Patients Recovered From Respiratory Disease)
- Being tested
- Asymmetric nasal cannula - DUET, Conventional nasal high flow cannula
- Medical subject headings
- Respiration Disorders
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Asymmetric nasal cannula - DUETDevice
DUET asymmetric nasal high flow interface that fits best to patients' nostrils (size: one nostril of the patient should be fully occluded) Patients will be crossed - over between the 2 interventions
Conventional nasal high flow cannulaDevice
Well - established conventional nasal high flow cannula (size: medium) Patients will be cross - over between the 2 interventions
| Study group | Role | What they receive |
|---|---|---|
| Recovery patients from respiratory disease - Asymmetric or conventional nasal high flow cannula | Experimental | Patients recovered from acute respiratory disease will be randomized to NHF oxygen therapy with asymmetrical cannula or conventional cannula Receives: Device: Asymmetric nasal cannula - DUET; Device: Conventional nasal high flow cannula |
| Recovery patients from respiratory disease - Conventional or asymmetric nasal high flow cannula | Active comparator | Patients recovered from acute respiratory disease will be randomized to NHF oxygen therapy with conventional cannula or asymmetrical cannula Receives: Device: Asymmetric nasal cannula - DUET; Device: Conventional nasal high flow cannula |
What is being measured
The primary outcome is the main question the study is designed to answer.
Change in the pressure time product after the use of symmetrical high flow nasal interface for 15 minutes.
This outcome measures the change in the Pressure-Time Product (PTP) before and after the application of a symmetrical high-flow nasal interface (HFNI) in patients requiring noninvasive respiratory support. The PTP is a physiological index that reflects the work of breathing and respiratory muscle effort. It is calculated using airway pressure and inspiratory time data over a defined period. The primary goal is to assess whether the symmetrical HFNI leads to a measurable reduction in the PTP, indicating improved respiratory mechanics and decreased patient effort.
Measured: Baseline and 15 minutes
Change in the pressure time product after the use of asymmetrical nasal high flow interface for 15 minutes.
This outcome measures the change in the Pressure-Time Product (PTP) before and after the application of a symmetrical high-flow nasal interface (HFNI) in patients requiring noninvasive respiratory support. The PTP is a physiological index that reflects the work of breathing and respiratory muscle effort. It is calculated using airway pressure and inspiratory time data over a defined period. The primary goal is to assess whether the asymmetrical HFNI leads to a measurable reduction in the PTP, indicating improved respiratory mechanics and decreased patient effort.
Measured: Baseline and 15 minutes
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted15 Jul 2025
- Study start9 Apr 2024
- Primary completion1 Sep 2025 (estimated)
- Study completion1 Sep 2025 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Respiratory Disease (Clinically Stable Individuals - Patients Recovered From Respiratory Disease)Studies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Basic science
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Single blind
- Who is masked
- Outcomes assessor
- Enrolment
- 30 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Larissa University Hospital
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Ioannis Pantazopoulos, Larissa University Hospital
- Investigators
- Demosthenes Makris, Study chair, Professor of Intensive Care Unit, University Hospital of Larissa
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07066566
- Sponsor's protocol ID
- 16171
- Status last verified
- Jul 2025
- First submitted
- 24 Jun 2025
- Last updated
- 18 Jul 2025
- Results posted
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 18 Jul 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- The Effect of Asymmetrical vs. Symmetrical High Flow Nasal Cannula on the Work of Breathing: A Randomised Cross-over Study
- ClinicalTrials.gov ID
- NCT07066566
- Acronym / sponsor ID
- 16171
- Conditions
- Respiratory Disease (Clinically Stable Individuals - Patients Recovered From Respiratory Disease)
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 30 participants (estimated)
- Lead sponsor
- Larissa University HospitalUniversity, hospital or other
- Study start
- 9 Apr 2024 (actual)
- Primary completion
- 1 Sep 2025 (estimated)
- Study completion
- 1 Sep 2025 (estimated)
- First posted
- 15 Jul 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The goal of this study randomized single-center crossover study is to evaluate the impact of asymmetrical versus symmetrical nasal high flow (NHF) therapy on work of breathing (WOB). The main question it aims to answer are:
- Does the asymmetrical NHF interface improve the work of breathing compared to the symmetrical NHF interface? Researchers will compare the symmetrical NHF interface to the symmetrical NHF interface to see if the the asymmetrical interface has a greater impact on the work of breathing.
Participants will :
- receive NHF via both interfaces (FiO₂ 0.21, 50 L/min) for 15 minutes, in random order, with esophageal pressure monitoring and bioelectrical impedance analysis performed.
- baseline characteristics will me monitored throughout the interventions
- Esophageal pressure and minute ventilation will be monitored.
Detailed description
Each participant will undergo all phases of the study while seated comfortably, breathing room air. Vital signs, including blood pressure, heart rate, and peripheral oxygen saturation (%SpO₂), will be continuously monitored and recorded throughout.
Respiratory mechanics will be assessed using esophageal pressure (Pes) monitoring. A thin latex balloon catheter (10 cm long, 3-5 cm circumference; Cooper surgical, USA), filled with 0.5 mL of air, will be placed in the mid-esophagus (~45 cm from the nares) and will be connected to a pressure transducer (RSS-100HR, Hans Rudolph Inc., USA). Correct positioning will be confirmed by observing equal fluctuations in Pes and airway pressure (Paw) during occluded breaths. Balloon integrity will be verified before, after, and as needed during the procedure.
Participants will be instructed to breathe quietly on room air (FiO₂ 0.21) to allow for baseline assessment. Volume will be recorded using a heated pneumotachometer (Series 3813; Hans Rudolph Inc., USA) and the Research Pneumotach System (RSS100-HR), sampling at 50 Hz, a sampling rate exceeding the Nyquist criterion for respiratory signals. A bioelectrical impedance technology device (ExSpiron, Respiratory Motion Inc., Waltham, MA) will then be attached around the chest to assess lung volume changes.
Participants will then be randomized in a 1:1 ratio to one of two intervention sequences using a computer-generated randomization schedule.
- Sequence 1: Symmetrical NHF Interface - 3-minute washout period - Asymmetrical NHF Interface
- Sequence 2: Asymmetrical NHF Interface - 3-minute washout period - Symmetrical NHF Interface In the seated position, participants will both 15-minute phases, separated by a 3-minute washout period to prevent residual effects. During the "Symmetrical Interface" phase, participants will breathe using the conventional symmetrical NHF cannula, and during the asymmetrical phase, the asymmetrical interface (DUET, Fisher and Paykel Healthcare, Auckland, New Zealand) will be used. High-flow oxygen will be delivered using a commercial system (AIRVO 3; Fisher and Paykel Healthcare, Auckland, New Zealand) set at a flow of 50 L/min, temperature of 37°C, and FiO₂ of 0.21.
Study design
- Primary purpose
- Basic science
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Single blind (outcomes assessor)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Recovery patients from respiratory disease - Asymmetric or conventional nasal high flow cannula | Experimental | Device: Asymmetric nasal cannula - DUET, Device: Conventional nasal high flow cannulaPatients recovered from acute respiratory disease will be randomized to NHF oxygen therapy with asymmetrical cannula or conventional cannula |
| Recovery patients from respiratory disease - Conventional or asymmetric nasal high flow cannula | Active comparator | Device: Asymmetric nasal cannula - DUET, Device: Conventional nasal high flow cannulaPatients recovered from acute respiratory disease will be randomized to NHF oxygen therapy with conventional cannula or asymmetrical cannula |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (2 listed)
- age ≥18 years old
- absence of symptoms and signs of respiratory failure (SpO2>95% at FiΟ2 0.21)
Key exclusion criteria (4 listed)
- pregnancy
- SpO2<94% at FiΟ2 0.21
- neuromuscular disease
- contraindications to esophageal pressure monitoring (e.g., uncontrolled coagulopathy, esophageal disease, nasal trauma, allergy to local lidocaine)
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Asymmetric nasal cannula - DUETDUET asymmetric nasal high flow interface that fits best to patients' nostrils (size: one nostril of the patient should be fully occluded) Patients will be crossed - over between the 2 interventions | Device | Recovery patients from respiratory disease - Asymmetric or conventional nasal high flow cannula, Recovery patients from respiratory disease - Conventional or asymmetric nasal high flow cannula |
| Conventional nasal high flow cannulaWell - established conventional nasal high flow cannula (size: medium) Patients will be cross - over between the 2 interventions | Device | Recovery patients from respiratory disease - Asymmetric or conventional nasal high flow cannula, Recovery patients from respiratory disease - Conventional or asymmetric nasal high flow cannula |
Primary outcome
Change in the pressure time product after the use of symmetrical high flow nasal interface for 15 minutes.
Time frame: Baseline and 15 minutes
This outcome measures the change in the Pressure-Time Product (PTP) before and after the application of a symmetrical high-flow nasal interface (HFNI) in patients requiring noninvasive respiratory support. The PTP is a physiological index that reflects the work of breathing and respiratory muscle effort. It is calculated using airway pressure and inspiratory time data over a defined period. The primary goal is to assess whether the symmetrical HFNI leads to a measurable reduction in the PTP, indicating improved respiratory mechanics and decreased patient effort.
Change in the pressure time product after the use of asymmetrical nasal high flow interface for 15 minutes.
Time frame: Baseline and 15 minutes
This outcome measures the change in the Pressure-Time Product (PTP) before and after the application of a symmetrical high-flow nasal interface (HFNI) in patients requiring noninvasive respiratory support. The PTP is a physiological index that reflects the work of breathing and respiratory muscle effort. It is calculated using airway pressure and inspiratory time data over a defined period. The primary goal is to assess whether the asymmetrical HFNI leads to a measurable reduction in the PTP, indicating improved respiratory mechanics and decreased patient effort.
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 18 Jul 2025.
- Individual participant dataSharing planned: No
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Demosthenes Makris study chair
Professor of Intensive Care Unit, University Hospital of Larissa
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Asymmetric nasal cannula - DUET and Conventional nasal high flow cannula in people with Respiratory Disease (Clinically Stable Individuals - Patients Recovered From Respiratory Disease), run by Larissa University Hospital at 1 site in Greece.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 2 inclusion and 4 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 18 Jul 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Greece. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Ioannis Dr. Pantazopoulos, Associate Professor (+30- 6945661525, pantazopoulosioannis@yahoo.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Change in the pressure time product after the use of symmetrical high flow nasal interface for 15 minutes. (time frame: Baseline and 15 minutes). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 18 Jul 2025.