Healthy
Conditions
Keywords
high-flow nasal cannula, ventilation distribution, lung impedance
Brief summary
This prospective, randomized crossover trial will enroll adult healthy volunteers. Initially, the subject's peak inspiratory flow will be measured using a mask connected with a respiratory monitor. Subsequently, the volunteers will undergo HFNC treatment at different flow settings while their peak inspiratory flow will be continuously monitored. The primary outcome of this study is the lung aeration with different flow settings. Secondary outcomes include the lung aeration with different devices, subject's comfort at different flow settings, and the correlation between the subject's peak inspiratory flow measured by HFNC and by a mask connected with a respiratory monitor.
Detailed description
Background: High-flow nasal cannula (HFNC) is a device that can reduce the work of breathing (WOB) and improve oxygenation by providing a flow that matches or exceeds patient's peak inspiratory flow during tidal breathing. Despite its widespread use, there remains a lack of consensus regarding the optimal flow settings. Two new HFNC devices that can provide information regarding patient's peak tidal inspiratory flow breath by breath are recently available, which might help guide set and titrate the flow settings. This study aims to investigate the effects of different flow settings on lung impedance in a cohort of healthy volunteers by using the two new HFNC devices. Methods: This prospective, randomized crossover trial will enroll adult healthy volunteers. Initially, the subject's peak inspiratory flow will be measured using a mask connected with a respiratory monitor. Subsequently, the volunteers will undergo HFNC treatment at different flow settings while their peak inspiratory flow will be continuously monitored. The primary outcome of this study is the lung aeration with different flow settings. Secondary outcomes include the lung aeration with different devices, subject's comfort at different flow settings, and the correlation between the subject's peak inspiratory flow measured by HFNC and by a mask connected with a respiratory monitor.
Interventions
DEVICEHigh-flow nasal cannula device with flow setting at 40 L/min or higher
Eligible participants will use the high-flow nasal cannula device (Airvo3 or HFT 750) with flow set at 40 L/min or higher
Sponsors
Rush University Medical Center
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
OTHER
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
21 Years to 65 Years
Healthy volunteers
Yes
Inclusion criteria
* Healthy volunteers between 21-65 years old
Exclusion criteria
* Chronic pulmonary diseases, including COPD, interstitial lung disease, cystic fibrosis, etc. * Uncontrolled asthma; * Pregnancy * Subjects who have cold/flu symptoms (sore throat, runny nose, fever, chills, coughing) * Nose abnormalities that can affect the functionality of the nasal prongs
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in End-expiratory Lung Impedance From Baseline Measured by Electrical Impedance Tomography (EIT) | Up to 4 hours | End-expiratory lung impedance (EELI) was measured continuously using electrical impedance tomography (EIT). For each flow-setting condition, EELI values were averaged over a stable 1-minute period. The outcome represents the change in EELI (in arbitrary impedance units) from each participant's baseline measurement prior to intervention. Positive values indicate an increase in end-expiratory lung volume compared to baseline, while negative values indicate a decrease. EIT impedance units are dimensionless and device-specific and are used to represent relative changes in ventilation and lung volume. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Changes in Respiratory Rates Compared to Baseline | Up to 4 hours | Respiratory rate was measured as breaths per minute. Change was calculated as the value during each HFNC flow condition minus the baseline respiratory rate. Positive values indicate an increase in respiratory rate, and negative values indicate a decrease. |
| Subject's Comfort Level | Up to 4 hours | Comfort level reported by participants using a visual numerical scale ranging between 0 (extreme discomfort) and 10 (very comfortable) at the end of each flow setting |
Countries
United States
Participant flow
Recruitment details
Adult healthy volunteers were recruited at a single academic medical center through posted study invitations and direct approach. Individuals expressing interest were screened for eligibility, and those who met inclusion criteria provided written informed consent prior to participation
Pre-assignment details
Adult healthy volunteers were recruited at a single academic medical center through posted study invitations and direct approach. Individuals expressing interest were screened for eligibility, and those who met inclusion criteria provided written informed consent prior to participation
Participants by arm
| Arm | Count |
|---|---|
| Total Study Population This randomized crossover study assigned all participants to receive each of the study treatments in a randomized order. All 26 participants contributed baseline demographic data to this single group. | 26 |
| Total | 26 |
Baseline characteristics
| Characteristic | Total Study Population |
|---|---|
| Age, Continuous | 27 years |
| Height | 163 centimeter |
| Race/Ethnicity, Customized African American | 2 Participants |
| Race/Ethnicity, Customized Asian | 6 Participants |
| Race/Ethnicity, Customized Caucasian | 11 Participants |
| Race/Ethnicity, Customized Hispanic/Latino | 6 Participants |
| Race/Ethnicity, Customized Other | 1 Participants |
| Sex: Female, Male Female | 18 Participants |
| Sex: Female, Male Male | 8 Participants |
| weight | 68.0 kilogram |
Adverse events
| Event type | EG000 affected / at risk |
|---|---|
| deaths Total, all-cause mortality | 0 / 26 |
| other Total, other adverse events | 0 / 26 |
| serious Total, serious adverse events | 0 / 26 |
Outcome results
Primary
Change in End-expiratory Lung Impedance From Baseline Measured by Electrical Impedance Tomography (EIT)
End-expiratory lung impedance (EELI) was measured continuously using electrical impedance tomography (EIT). For each flow-setting condition, EELI values were averaged over a stable 1-minute period. The outcome represents the change in EELI (in arbitrary impedance units) from each participant's baseline measurement prior to intervention. Positive values indicate an increase in end-expiratory lung volume compared to baseline, while negative values indicate a decrease. EIT impedance units are dimensionless and device-specific and are used to represent relative changes in ventilation and lung volume.
Time frame: Up to 4 hours
Population: All enrolled participants (n=26) were included in this baseline analysis.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Total Study Population | Change in End-expiratory Lung Impedance From Baseline Measured by Electrical Impedance Tomography (EIT) | EELI change with HFNC 20 L/min compared to baseline for HFT device | 9 Change in EELI (arbitrary units) | Standard Deviation 44 |
| Total Study Population | Change in End-expiratory Lung Impedance From Baseline Measured by Electrical Impedance Tomography (EIT) | EELI change with HFNC 40 L/min compared to baseline for HFT device | 74 Change in EELI (arbitrary units) | Standard Deviation 80 |
| Total Study Population | Change in End-expiratory Lung Impedance From Baseline Measured by Electrical Impedance Tomography (EIT) | EELI change with HFNC 60 L/min compared to baseline for HFT device | 132 Change in EELI (arbitrary units) | Standard Deviation 104 |
| Total Study Population | Change in End-expiratory Lung Impedance From Baseline Measured by Electrical Impedance Tomography (EIT) | EELI change with HFNC 20 L/min compared to baseline for AIRVO device | 7 Change in EELI (arbitrary units) | Standard Deviation 44 |
| Total Study Population | Change in End-expiratory Lung Impedance From Baseline Measured by Electrical Impedance Tomography (EIT) | EELI change with HFNC 40 L/min compared to baseline for AIRVO device | 71 Change in EELI (arbitrary units) | Standard Deviation 71 |
| Total Study Population | Change in End-expiratory Lung Impedance From Baseline Measured by Electrical Impedance Tomography (EIT) | change with HFNC 60 L/min compared to baseline for AIRVO device | 111 Change in EELI (arbitrary units) | Standard Deviation 77 |
Secondary
Changes in Respiratory Rates Compared to Baseline
Respiratory rate was measured as breaths per minute. Change was calculated as the value during each HFNC flow condition minus the baseline respiratory rate. Positive values indicate an increase in respiratory rate, and negative values indicate a decrease.
Time frame: Up to 4 hours
Population: All enrolled participants (n=26) were included in this baseline analysis.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Total Study Population | Changes in Respiratory Rates Compared to Baseline | Changes in respiratory rates at HFNC 20 L/min compared to baseline for HFT device | -1.6 breaths per minute | Standard Deviation 3 |
| Total Study Population | Changes in Respiratory Rates Compared to Baseline | Changes in respiratory rates at HFNC 40 L/min compared to baseline for HFT device | -3.7 breaths per minute | Standard Deviation 5.6 |
| Total Study Population | Changes in Respiratory Rates Compared to Baseline | Changes in respiratory rates at HFNC 60 L/min compared to baseline for HFT device | -5.0 breaths per minute | Standard Deviation 4.2 |
| Total Study Population | Changes in Respiratory Rates Compared to Baseline | Changes in respiratory rates at HFNC 20 L/min compared to baseline for AIRVO device | -3.1 breaths per minute | Standard Deviation 3.2 |
| Total Study Population | Changes in Respiratory Rates Compared to Baseline | Changes in respiratory rates at HFNC 40 L/min compared to baseline for AIRVO device | -3.1 breaths per minute | Standard Deviation 4 |
| Total Study Population | Changes in Respiratory Rates Compared to Baseline | Changes in respiratory rates at HFNC 60 L/min compared to baseline for AIRVO device | -4.8 breaths per minute | Standard Deviation 6.1 |
Secondary
Subject's Comfort Level
Comfort level reported by participants using a visual numerical scale ranging between 0 (extreme discomfort) and 10 (very comfortable) at the end of each flow setting
Time frame: Up to 4 hours
Population: All enrolled participants (n=26) were included in this baseline analysis.
| Arm | Measure | Group | Value (MEDIAN) |
|---|---|---|---|
| Total Study Population | Subject's Comfort Level | Comfort level at HFNC 20 L/min for AIRVO device | 9 Score (0-10) |
| Total Study Population | Subject's Comfort Level | Comfort level at HFNC 40 L/min for AIRVO device | 8 Score (0-10) |
| Total Study Population | Subject's Comfort Level | Comfort level at HFNC 60 L/min for AIRVO device | 8 Score (0-10) |
| Total Study Population | Subject's Comfort Level | Comfort level at HFNC 20 L/min for HFT device | 9 Score (0-10) |
| Total Study Population | Subject's Comfort Level | Comfort level at HFNC 40 L/min for HFT device | 8 Score (0-10) |
| Total Study Population | Subject's Comfort Level | Comfort level at HFNC 60 L/min for HFT device | 7 Score (0-10) |