Trial Outcomes & Findings for The Effects of Different Flow Settings on Lung Impedance (NCT NCT06228703)

Last Updated: 2025-12-19

Results Overview

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.

Recruitment status

COMPLETED

Study phase

Target enrollment

26 participants

Primary outcome timeframe

Up to 4 hours

Results posted on

2025-12-19

Participant Flow

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

Participant milestones

Participant milestones
Measure	Total Study Population This randomized crossover study evaluated two high-flow nasal cannula devices. All 26 participants completed the three prespecified flow-setting conditions for each device in a randomized sequence.
Device A - Flow Setting 1 STARTED	26
Device A - Flow Setting 1 COMPLETED	26
Device A - Flow Setting 1 NOT COMPLETED	0
Device A - Flow Setting 2 STARTED	26
Device A - Flow Setting 2 COMPLETED	26
Device A - Flow Setting 2 NOT COMPLETED	0
Device A - Flow Setting 3 STARTED	26
Device A - Flow Setting 3 COMPLETED	26
Device A - Flow Setting 3 NOT COMPLETED	0
Device B - Flow Setting 1 STARTED	26
Device B - Flow Setting 1 COMPLETED	26
Device B - Flow Setting 1 NOT COMPLETED	0
Device B - Flow Setting 2 STARTED	26
Device B - Flow Setting 2 COMPLETED	26
Device B - Flow Setting 2 NOT COMPLETED	0
Device B - Flow Setting 3 STARTED	26
Device B - Flow Setting 3 COMPLETED	26
Device B - Flow Setting 3 NOT COMPLETED	0

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

All enrolled participants (n=26) were included in this baseline analysis.

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Total Study Population n=26 Participants 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.
Age, Continuous	27 years n=8 Participants
Sex: Female, Male Female	18 Participants n=8 Participants • All enrolled participants (n=26) were included in this baseline analysis.
Sex: Female, Male Male	8 Participants n=8 Participants • All enrolled participants (n=26) were included in this baseline analysis.
Race/Ethnicity, Customized Caucasian	11 Participants n=8 Participants • All enrolled participants (n=26) were included in this baseline analysis.
Race/Ethnicity, Customized Asian	6 Participants n=8 Participants • All enrolled participants (n=26) were included in this baseline analysis.
Race/Ethnicity, Customized Hispanic/Latino	6 Participants n=8 Participants • All enrolled participants (n=26) were included in this baseline analysis.
Race/Ethnicity, Customized African American	2 Participants n=8 Participants • All enrolled participants (n=26) were included in this baseline analysis.
Race/Ethnicity, Customized Other	1 Participants n=8 Participants • All enrolled participants (n=26) were included in this baseline analysis.
Height	163 centimeter n=8 Participants • All enrolled participants (n=26) were included in this baseline analysis.
weight	68.0 kilogram n=8 Participants

PRIMARY outcome

Timeframe: Up to 4 hours

Population: All enrolled participants (n=26) were included in this baseline analysis.

Outcome measures

Outcome measures
Measure	Total Study Population n=26 Participants 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.
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
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
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
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
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
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 outcome

Timeframe: Up to 4 hours

Population: All enrolled participants (n=26) were included in this baseline analysis.

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.

Outcome measures

Outcome measures
Measure	Total Study Population n=26 Participants 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.
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 3.0
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
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
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
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 4.0
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 outcome

Timeframe: Up to 4 hours

Population: All enrolled participants (n=26) were included in this baseline analysis.

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

Outcome measures

Outcome measures
Measure	Total Study Population n=26 Participants 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.
Subject's Comfort Level Comfort level at HFNC 20 L/min for HFT device	9 Score (0-10) Interval 9.0 to 10.0
Subject's Comfort Level Comfort level at HFNC 40 L/min for HFT device	8 Score (0-10) Interval 7.0 to 8.0
Subject's Comfort Level Comfort level at HFNC 60 L/min for HFT device	7 Score (0-10) Interval 6.0 to 8.0
Subject's Comfort Level Comfort level at HFNC 20 L/min for AIRVO device	9 Score (0-10) Interval 9.0 to 9.0
Subject's Comfort Level Comfort level at HFNC 40 L/min for AIRVO device	8 Score (0-10) Interval 8.0 to 9.0
Subject's Comfort Level Comfort level at HFNC 60 L/min for AIRVO device	8 Score (0-10) Interval 7.0 to 8.0

Adverse Events

Total Study Population

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

Jie Li

Rush University

Phone: 3125634643

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place