Acute Respiratory Failure (ARF)NCT07247318
The Effects of Different Non-invasive Respiratory Support
A study testing Continuous Positive Airway Pressure, Non-invasive ventilation and High-flow nasal oxygen in people with Acute Respiratory Failure (ARF), run by Southeast University, China.
Trial summary
Patients with acute hypoxemic respiratory failure (AHRF) typically present with pathophysiological alterations characterized by the coexistence of respiratory dysfunction and hypoxemia. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Acute Respiratory Failure (ARF)
- What is being tested?
- Continuous Positive Airway Pressure, Non-invasive ventilation and High-flow nasal oxygen
- Type of treatment
- Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 60 participants
- Where
- No sites listed yet
- Study dates
- 30 Nov 2025to 31 Dec 2026
- 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
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Age ≥ 18 years;
- PaO₂/FiO₂ ≤ 300 mmHg or SpO₂/FiO₂ ≤ 315 (with SpO₂ ≤ 97%);
- Requiring one of the following respiratory supports:
- Noninvasive positive pressure ventilation with PEEP ≥ 5 cmH₂O, or
- High-flow nasal oxygen therapy with a flow rate ≥ 30 L/min, or
- Conventional oxygen therapy with an oxygen flow ≥ 10 L/min, where FiO₂ is calculated using the formula: FiO₂ = 0.21 + (oxygen flow rate × 0.03).
Who cannot join
- Received CPAP or NIV for more than 24 hours prior to screening.
- Received invasive mechanical ventilation during the current hospitalization.
- Presence of chronic underlying pulmonary disease, or PaCO₂ ≥ 45 mmHg.
- Presence of cardiogenic pulmonary edema.
- Hemodynamic instability, defined as systolic blood pressure < 90 mmHg or norepinephrine-equivalent dose > 0.3 µg/kg/min.
- Impaired consciousness (GCS ≤ 12).
Show all 11Show fewer
- Patients requiring urgent intubation, including those with respiratory or cardiac arrest, apnea with loss of consciousness or gasping, or severe hypoxemia (defined as SpO₂ < 90% despite 100% oxygen).
- Contraindications to NIV: cardiac or respiratory arrest, coma, untreated pneumothorax, uncontrollable vomiting, upper airway obstruction, hematemesis or severe facial trauma, or thoracic/abdominal surgery within the past 7 days.
- Contraindications to EIT: implanted cardiac pacemaker, unstable spinal injury or fracture, or open chest trauma.
- Refusal of endotracheal intubation.
- Pregnancy.
About this study
Official title: The Physiological Effects of Different Non-invasive Respiratory Support in Patients With Acute Hypoxemic Respiratory
Patients with acute hypoxemic respiratory failure (AHRF) typically present with pathophysiological alterations characterized by the coexistence of respiratory dysfunction and hypoxemia. Respiratory dysfunction leads to dyspnea, increased work of breathing, use of accessory respiratory muscles, and hypercapnia, while gas exchange impairment results in hypoxemia. Studies have shown that hypercapnia, acidosis, and hypoxemia can all enhance inspiratory effort, which further increases negative intrathoracic pressure. In these patients, regional differences in airway resistance and lung compliance are often present, causing redistribution of air within the lungs. This redistribution manifests as gas movement from non-dependent to dependent regions, known as "pendelluft," which amplifies regional alveolar strain and ventilation heterogeneity. This phenomenon becomes more pronounced during noninvasive respiratory support when spontaneous breathing is preserved.
Noninvasive respiratory support strategies mainly include high-flow nasal oxygen (HFNO), noninvasive positive pressure ventilation (NIV), and continuous positive airway pressure (CPAP). HFNO delivers high-flow gas through nasal cannulas, generating a certain level of positive end-expiratory pressure (PEEP) and flushing out anatomical dead space to improve gas exchange, thereby reducing inspiratory effort, lowering the work of breathing, and enhancing oxygenation. NIV, typically using pressure support ventilation (NIV-PSV), is a patient-triggered, pressure-targeted mode that provides inspiratory positive pressure above PEEP. By augmenting tidal volume and reducing inspiratory effort, NIV improves gas exchange; however, leaks may limit the effective delivery of PEEP, and full inspiratory synchronization can increase transpulmonary driving pressure and tidal volume. CPAP, by contrast, delivers a constant positive pressure during both inspiration and expiration. Compared with HFNO, CPAP generates higher PEEP, which facilitates alveolar recruitment and more effectively improves oxygenation. Relative to NIV, CPAP may reduce transpulmonary driving pressure and tidal volume.
Different noninvasive respiratory support strategies exert varying effects on respiratory drive and regional lung strain, leading to differences in the occurrence and magnitude of pendelluft. Physiological studies have suggested that CPAP may offer greater benefits in improving oxygenation and reducing inspiratory effort; however, whether it can mitigate the occurrence and extent of pendelluft remains uncertain. Therefore, this study was conducted to visualize and quantitatively assess pendelluft in real time using electrical impedance tomography (EIT), aiming to verify whether CPAP has a superior effect in reducing pendelluft in patients with AHRF.
- Conditions
- Acute Respiratory Failure (ARF)
- Being tested
- Continuous Positive Airway Pressure, Non-invasive ventilation, High-flow nasal oxygen
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Continuous Positive Airway PressureDevice
Patients were placed at a 45-degree supine position, and noninvasive ventilation was delivered to the patient through a face mask connected to an ICU ventilator. 2.PEEP was started at 5 cm H2O with a FiO2 of 0.5 at initiation. PEEP and FiO2 were titrated to maintain SpO2 between 94 and 98%, remaining constant for at least 5 min. 3.CPAP was initiated with a first session of at least 4 h, the minimally required duration of noninvasive ventilation was 16 hours per day for at least 2 calendar days. Between noninvasive-ventilation sessions, patients received HFNO.
Non-invasive ventilationDevice
Patients were placed at a 45-degree supine position, and noninvasive ventilation was also delivered to the patient through a face mask connected to an ICU ventilator. The mask most appropriate for the patient will be selected and adjusted to minimize leakage and pressure points. 2. The inspiratory positive airway pressure (pressure support plus PEEP) was initiated between 12 and 14 cm H2O, PEEP was started at 5 cm H2O with a FiO2 of 0.5 at initiation. FiO2 was titrated to maintain SpO2 between 94 and 98%, remaining constant for at least 5 min. 3. NIV was initiated with a first session of at least 4 h, the minimally required duration of noninvasive ventilation was 16 hours per day for at least 2 calendar days. Between noninvasive-ventilation sessions, patients received HFNO.
High-flow nasal oxygenDevice
Oxygen was passed through a heated humidifier (MR850, Fisher and Paykel Healthcare) and applied continuously through large-bore binasal prongs, with a gas flow rate of 50 liters per minute and an FiO2 of 0.5 at initiation. HFNO heating temperature was prespecified at 37°C. 2.FiO2 will be titrated to maintain SpO2 between 94 and 98%, remaining constant for at least 5 min. 3.HFNO was applied for at least 2 calendar days.
| Study group | Role | What they receive |
|---|---|---|
| CPAP group | Experimental | Patients will receive continuous positive airway pressure Receives: Device: Continuous Positive Airway Pressure |
| NIV group | Experimental | Patients will receive non-invasive ventilation Receives: Device: Non-invasive ventilation |
| HFNO group | Experimental | Patients will receive HFNO Receives: Device: High-flow nasal oxygen |
What is being measured
The primary outcome is the main question the study is designed to answer.
Magnitude of Pendelluft
magnitude of Pendelluft using a software based on electrical impedance tomography monitoring
Measured: during the first 48 hours
Secondary outcomes (8)
pH
Arterial blood gas analysis
Measured: during the first 48 hours
Partial pressure of oxygen (PaO2)
Arterial blood gas analysis
Measured: during the first 48 hours
Partial Pressure of Carbon Dioxide (PaCO2)
Arterial blood gas analysis
Measured: during the first 48 hours
Pao2/FiO2
Arterial blood gas analysis
Measured: during the first 48 hours
Occlusion pressure at 100 ms (P0.1)
Monitoring with non-invasive ventilator
Measured: during the first 48 hours
Occluded inspiratory airway pressure (Pocc)
Monitoring with a non-invasive ventilator
Measured: during the first 48 hours
center of ventilation
monitoring with EIT
Measured: during the first 48 hours
RVD
Monitoring with EIT
Measured: during the first 48 hours
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted25 Nov 2025
- Study start30 Nov 2025 (estimated)
- Primary completion31 Dec 2026 (estimated)
- Study completion31 Dec 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Acute Respiratory Failure (ARF)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
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 60 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Southeast University, China
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Ling Liu, Southeast University, China
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07247318
- Sponsor's protocol ID
- Non-invasive support
- Status last verified
- Nov 2025
- First submitted
- 14 Nov 2025
- Last updated
- 25 Nov 2025
- Results posted
- No
- Data monitoring committee
- Yes
- 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 25 Nov 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- The Physiological Effects of Different Non-invasive Respiratory Support in Patients With Acute Hypoxemic Respiratory
- ClinicalTrials.gov ID
- NCT07247318
- Acronym / sponsor ID
- Non-invasive support
- Conditions
- Acute Respiratory Failure (ARF)
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 60 participants (estimated)
- Lead sponsor
- Southeast University, ChinaUniversity, hospital or other
- Study start
- 30 Nov 2025 (estimated)
- Primary completion
- 31 Dec 2026 (estimated)
- Study completion
- 31 Dec 2026 (estimated)
- First posted
- 25 Nov 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.
Patients with acute hypoxemic respiratory failure (AHRF) typically present with pathophysiological alterations characterized by the coexistence of respiratory dysfunction and hypoxemia. Respiratory dysfunction leads to dyspnea, increased work of breathing, use of accessory respiratory muscles, and hypercapnia, while gas exchange impairment results in hypoxemia. Studies have shown that hypercapnia, acidosis, and hypoxemia can all enhance inspiratory effort, which further increases negative intrathoracic pressure. In these patients, regional differences in airway resistance and lung compliance are often present, causing redistribution of air within the lungs. This redistribution manifests as gas movement from non-dependent to dependent regions, known as "pendelluft," which amplifies regional alveolar strain and ventilation heterogeneity. This phenomenon becomes more pronounced during noninvasive respiratory support when spontaneous breathing is preserved.
Noninvasive respiratory support strategies mainly include high-flow nasal oxygen (HFNO), noninvasive positive pressure ventilation (NIV), and continuous positive airway pressure (CPAP). HFNO delivers high-flow gas through nasal cannulas, generating a certain level of positive end-expiratory pressure (PEEP) and flushing out anatomical dead space to improve gas exchange, thereby reducing inspiratory effort, lowering the work of breathing, and enhancing oxygenation. NIV, typically using pressure support ventilation (NIV-PSV), is a patient-triggered, pressure-targeted mode that provides inspiratory positive pressure above PEEP. By augmenting tidal volume and reducing inspiratory effort, NIV improves gas exchange; however, leaks may limit the effective delivery of PEEP, and full inspiratory synchronization can increase transpulmonary driving pressure and tidal volume. CPAP, by contrast, delivers a constant positive pressure during both inspiration and expiration. Compared with HFNO, CPAP generates higher PEEP, which facilitates alveolar recruitment and more effectively improves oxygenation. Relative to NIV, CPAP may reduce transpulmonary driving pressure and tidal volume.
Different noninvasive respiratory support strategies exert varying effects on respiratory drive and regional lung strain, leading to differences in the occurrence and magnitude of pendelluft. Physiological studies have suggested that CPAP may offer greater benefits in improving oxygenation and reducing inspiratory effort; however, whether it can mitigate the occurrence and extent of pendelluft remains uncertain. Therefore, this study was conducted to visualize and quantitatively assess pendelluft in real time using electrical impedance tomography (EIT), aiming to verify whether CPAP has a superior effect in reducing pendelluft in patients with AHRF.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 3
| Arm | Type | Receives |
|---|---|---|
| CPAP group | Experimental | Device: Continuous Positive Airway PressurePatients will receive continuous positive airway pressure |
| NIV group | Experimental | Device: Non-invasive ventilationPatients will receive non-invasive ventilation |
| HFNO group | Experimental | Device: High-flow nasal oxygenPatients will receive HFNO |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (6 listed)
- Age ≥ 18 years;
- PaO₂/FiO₂ ≤ 300 mmHg or SpO₂/FiO₂ ≤ 315 (with SpO₂ ≤ 97%);
- Requiring one of the following respiratory supports:
Key exclusion criteria (11 listed)
- Received CPAP or NIV for more than 24 hours prior to screening.
- Received invasive mechanical ventilation during the current hospitalization.
- Presence of chronic underlying pulmonary disease, or PaCO₂ ≥ 45 mmHg.
- Presence of cardiogenic pulmonary edema.
- Hemodynamic instability, defined as systolic blood pressure < 90 mmHg or norepinephrine-equivalent dose > 0.3 µg/kg/min.
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 |
|---|---|---|
| Continuous Positive Airway PressurePatients were placed at a 45-degree supine position, and noninvasive ventilation was delivered to the patient through a face mask connected to an ICU ventilator. 2.PEEP was started at 5 cm H2O with a FiO2 of 0.5 at initiation. PEEP and FiO2 were titrated to maintain SpO2 between 94 and 98%, remaining constant for at least 5 min. 3.CPAP was initiated with a first session of at least 4 h, the minimally required duration of noninvasive ventilation was 16 hours per day for at least 2 calendar days. Between noninvasive-ventilation sessions, patients received HFNO. | Device | CPAP group |
| Non-invasive ventilationPatients were placed at a 45-degree supine position, and noninvasive ventilation was also delivered to the patient through a face mask connected to an ICU ventilator. The mask most appropriate for the patient will be selected and adjusted to minimize leakage and pressure points. 2. The inspiratory positive airway pressure (pressure support plus PEEP) was initiated between 12 and 14 cm H2O, PEEP was started at 5 cm H2O with a FiO2 of 0.5 at initiation. FiO2 was titrated to maintain SpO2 between 94 and 98%, remaining constant for at least 5 min. 3. NIV was initiated with a first session of at least 4 h, the minimally required duration of noninvasive ventilation was 16 hours per day for at least 2 calendar days. Between noninvasive-ventilation sessions, patients received HFNO. | Device | NIV group |
| High-flow nasal oxygenOxygen was passed through a heated humidifier (MR850, Fisher and Paykel Healthcare) and applied continuously through large-bore binasal prongs, with a gas flow rate of 50 liters per minute and an FiO2 of 0.5 at initiation. HFNO heating temperature was prespecified at 37°C. 2.FiO2 will be titrated to maintain SpO2 between 94 and 98%, remaining constant for at least 5 min. 3.HFNO was applied for at least 2 calendar days. | Device | HFNO group |
Primary outcome
Magnitude of Pendelluft
Time frame: during the first 48 hours
magnitude of Pendelluft using a software based on electrical impedance tomography monitoring
8 secondary outcomes
pH
Time frame: during the first 48 hours
Partial pressure of oxygen (PaO2)
Time frame: during the first 48 hours
Partial Pressure of Carbon Dioxide (PaCO2)
Time frame: during the first 48 hours
Pao2/FiO2
Time frame: during the first 48 hours
Occlusion pressure at 100 ms (P0.1)
Time frame: during the first 48 hours
Occluded inspiratory airway pressure (Pocc)
Time frame: during the first 48 hours
center of ventilation
Time frame: during the first 48 hours
RVD
Time frame: during the first 48 hours
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 25 Nov 2025.
- Individual participant dataSharing planned: No
Related trials for Acute Respiratory Failure (ARF)
Not yet recruiting
Regional Lung Ventilation During Prone Position in in Intubated Children
Pediatric Acute Respiratory Failure
Not yet recruiting
ICU-SUCCEED for Survivors of Acute Respiratory Failure and Their Caregivers
Acute Respiratory Failure, Critical Illness
Not yet recruitingObservational study
Lactate/Albumin Ratio and Mortality in Respiratory Failure
Acute Respiratory Failure, Critical Illness
RecruitingPhase 3
Efficacy and Safety of Tozorakimab in Patients Hospitalised for Viral Lung Infection Requiring Supplemental Oxygen
Viral Lung Infection and Acute Respiratory Failure
RecruitingPhase 3
Optimizing Pain Treatment in Children On Mechanical Ventilation
Mechanical Ventilation, Pediatric Acute Respiratory Failure
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.
The record lists no contact. Use the official record to reach the sponsor.
Questions about this trial
What is this clinical trial studying?
A study testing Continuous Positive Airway Pressure, Non-invasive ventilation and High-flow nasal oxygen in people with Acute Respiratory Failure (ARF), run by Southeast University, China.
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 6 inclusion and 11 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: opening soon, as of the sponsor's last update on 25 Nov 2025. Status can change between updates, so confirm with the study contact before making plans.
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?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Magnitude of Pendelluft (time frame: during the first 48 hours). 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 25 Nov 2025.