Physiological Effects of High-flow Nasal Cannula During Exercise

Effects of High-flow Nasal Cannula on the Distribution of Pulmonary Ventilation and Respiratory Effort in Healthy Subjects During Exercise.

The high-flow nasal cannula (HFNC) has increased its evidence in patients during pulmonary rehabilitation. These studies hypothesize that the physiological effects of HFNC (positive expiratory pressure, anatomical dead space lavage, thermo-humidification) lead to an increase in exercise time. This is believed to be due to improvements that the device can generate in the respiratory system and muscles. However, the physiological effects of HFNC on respiratory effort and distribution of pulmonary ventilation during exercise are unknown. The aim of this study is to determine the acute effect of high flow nasal cannula on the distribution of pulmonary ventilation and respiratory effort during physical exercise in healthy subjects.

Study Overview

• Status: Completed
• Conditions: Healthy Volunteers
• Intervention / Treatment: Device: High-flow Nasal Cannula

Detailed Description

A randomized, cross-over clinical trial in which either HFNC or Sham may be used as an adjunct on a cycle ergometer in random order will be performed to compare the respiratory effort and distribution of pulmonary ventilation continuously. Measurements will be taken in a warm-up, exercise, and recovery phase for both groups.

• Study Type: Interventional
• Enrollment (Actual): 14
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Chile
  • Provincia
    • Santiago, Provincia, Chile, 7820436
      • Laboratorio de Fisiología del Ejercicio, Departamento Ciencias de la Salud, Facultad de Medicina, Pontificia Universidad Católica de Chile.

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 45 years (Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Healthy adults volunteers
• Physically inactive (according to World Health Organization criteria).

Exclusion Criteria:

• Refusal to participate
• Smokers
• History of acute cardiorespiratory or musculoskeletal disease during the last year (including COVID-19 when hospitalization or supplemental oxygen was required without any other disease)
• Any neuromuscular or cardiovascular or condition that limits test performance.
• Contraindication for esophageal catheter installation (recent epistaxis, severe coagulopathy, among other).

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: HFNC Group; Healthy subject will perform one Constant Work-Rate Exercise Test at respiratory compensation point as determined by a cardiopulmonary exercise test with High Flow Nasal at 60L/min (without additional oxygen)	Device: High-flow Nasal Cannula; HFNC is a device that, in this study, will give the maximum flow (60 L/min), with minimum adjusted temperature (31°C) and FiO2 of 21% or room air.; Other Names: HFNC
Sham Comparator: Control Group; Healthy subject will perform one Constant Work-Rate Exercise Test at respiratory compensation point as determined by a cardiopulmonary exercise test with High Flow Nasal at 2L/min (without additional oxygen)	Device: High-flow Nasal Cannula; HFNC is a device that, in this study, will give the maximum flow (60 L/min), with minimum adjusted temperature (31°C) and FiO2 of 21% or room air.; Other Names: HFNC

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Inspiratory effort	The average esophageal pressure swings during inspiration (ΔPes) defined as the absolute differences between end-expiratory and end-inspiratory Pes over a period of 60 seconds. Measurements will be during warm-up (one minute of five minutes), exercise (minutes: 0-1'; 3-4'; 5-6'), and the recovery phase (minutes: 0-1'; 1-2'; 3-4'; 5-6';7-8';9-10') for both groups.	at 3 weeks. Outcome will be measured during the CWRET and will be carried out on different days, separate from approximately 7 days, for a total time frame of 3 weeks maximum per participant. Data will be collected during warm-up, exercise, and recovery
Standard deviation of regional ventilation delay index (RVDsd)	as a measure of temporal distribution of ventilation: defined as the average of 10 breaths representative of the 60 seconds evaluated in each period. Measurements will be during warm-up (one minute of five minutes), exercise (minutes: 0-1'; 3-4'; 5-6'), and the recovery phase (minutes: 0-1'; 1-2'; 3-4'; 5-6';7-8';9-10') for both groups.	at 3 weeks. Outcome will be measured during the CWRET and will be carried out on different days, separate from approximately 7 days, for a total time frame of 3 weeks maximum per participant. Data will be collected during warm-up, exercise, and recovery

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Work of breathing	The average pressure time product over a minute (PTPmin), defined as the sum of the areas subtended by the Pes waveform during inspiration over 60 seconds. Measurements will be during warm-up (one minute of five minutes), exercise (minutes: 0-1'; 3-4'; 5-6'), and the recovery phase (minutes: 0-1'; 1-2'; 3-4'; 5-6';7-8';9-10') for both groups.	at 3 weeks. Outcome will be measured during the CWRET and will be carried out on different days, separate from approximately 7 days, for a total time frame of 3 weeks maximum per participant. Data will be collected during warm-up, exercise, and recovery
Work of breathing per single breath	The average per-breath pressure time product (PTP), defined as the area subtended by the Pes waveform during inspiration in a series of representative and valid breaths divided by the number of breaths (at least five to ten) over 60 seconds. Measurements will be during warm-up (one minute of five minutes), exercise (minutes: 0-1'; 3-4'; 5-6'), and the recovery phase (minutes: 0-1'; 1-2'; 3-4'; 5-6';7-8';9-10') for both groups.	at 3 weeks. Outcome will be measured during the CWRET and will be carried out on different days, separate from approximately 7 days, for a total time frame of 3 weeks maximum per participant. Data will be collected during warm-up, exercise, and recovery
Respiratory drive	The average of negative pressure measured 500 ms after the initiation of an inspiratory effort defined as the defection in Pes during the first 0.5 s during inspiration in a series of representative and valid breaths divided by the number of breaths (at least five to ten) over 60 seconds. Also, The average slope of the inspiratory negative Pes swings from the start of inspiration to the minimum pressure (ΔPes/Δt) in a series of representative and valid breaths divided by the number of breaths (at least five to ten) over 60 seconds. Measurements will be during warm-up (one minute of five minutes), exercise (minutes: 0-1'; 3-4'; 5-6'), and the recovery phase (minutes: 0-1'; 1-2'; 3-4'; 5-6';7-8';9-10') for both groups.	at 3 weeks. Outcome will be measured during the CWRET and will be carried out on different days, separate from approximately 7 days, for a total time frame of 3 weeks maximum per participant. Data will be collected during warm-up, exercise, and recovery
Tidal Variation (TV) as a measure of variation during tidal breathing	defined as the average of differences between end-expiratory lung impedance (EELI) and end-inspiratory lung impedance (EILV) in 60 seconds for each period evaluated warm-up (one minute of five minutes), exercise (minutes: 0-1'; 3-4'; 5-6'), and the recovery phase (minutes: 0-1'; 1-2'; 3-4'; 5-6';7-8';9-10') for both groups.	at 3 weeks. Outcome will be measured during the CWRET and will be carried out on different days, separate from approximately 7 days, for a total time frame of 3 weeks maximum per participant. Data will be collected during warm-up, exercise, and recovery
End-Expiratory Lung Impedance (EELI), as a measure lung aeration	average of end-expiratory lung impedance respectively, in 60 seconds for each period evaluated warm-up (one minute of five minutes), exercise (minutes: 0-1'; 3-4'; 5-6'), and the recovery phase (minutes: 0-1'; 1-2'; 3-4'; 5-6';7-8';9-10') for both groups.	at 3 weeks. Outcome will be measured during the CWRET and will be carried out on different days, separate from approximately 7 days, for a total time frame of 3 weeks maximum per participant. Data will be collected during warm-up, exercise, and recovery
Normalized Tidal Variation (TV) as a measure of variation during tidal breathing	defined as the average of differences between end-expiratory lung impedance (EELI) and end-inspiratory lung impedance (EILV) divided by the number of breaths evaluated in each period (60 seconds).Measurements will be during warm-up (one minute of five minutes), exercise (minutes: 0-1'; 3-4'; 5-6'), and the recovery phase (minutes: 0-1'; 1-2'; 3-4'; 5-6';7-8';9-10') for both groups.	at 3 weeks. Outcome will be measured during the CWRET and will be carried out on different days, separate from approximately 7 days, for a total time frame of 3 weeks maximum per participant. Data will be collected during warm-up, exercise, and recovery
Normalized End-Expiratory Lung Impedance (EELI)	as a measure lung aeration: defined as the average of end-expiratory lung impedance divided by the number of breaths evaluated in each period (60 seconds). Measurements will be during warm-up (one minute of five minutes), exercise (minutes: 0-1'; 3-4'; 5-6'), and the recovery phase (minutes: 0-1'; 1-2'; 3-4'; 5-6';7-8';9-10') for both groups.	at 3 weeks. Outcome will be measured during the CWRET and will be carried out on different days, separate from approximately 7 days, for a total time frame of 3 weeks maximum per participant. Data will be collected during warm-up, exercise, and recovery
Global inhomogeneity index (GI) as a measure of spatial distribution of tidal ventilation	defined as the value of the tidal image in 60 seconds for each period evaluated. Measurements will be during warm-up (one minute of five minutes), exercise (minutes: 0-1'; 3-4'; 5-6'), and the recovery phase (minutes: 0-1'; 1-2'; 3-4'; 5-6';7-8';9-10') for both groups.	at 3 weeks. Outcome will be measured during the CWRET and will be carried out on different days, separate from approximately 7 days, for a total time frame of 3 weeks maximum per participant. Data will be collected during warm-up, exercise, and recovery
Center of ventilation (COV), dorsal fraction of ventilation (TVd) and anterior-to-posterior ventilation ratio (Impedance ratio), most dorsal region of interest (ROI4) (TVroi4), as a measure of ventilation distribution influenced by gravity.	defined as the value of the tidal image in 60 seconds for each period evaluated. Measurements will be during warm-up (one minute of five minutes), exercise (minutes: 0-1'; 3-4'; 5-6'), and the recovery phase (minutes: 0-1'; 1-2'; 3-4'; 5-6';7-8';9-10') for both groups.	at 3 weeks. Outcome will be measured during the CWRET and will be carried out on different days, separate from approximately 7 days, for a total time frame of 3 weeks maximum per participant. Data will be collected during warm-up, exercise, and recovery
Dyspnea and leg fatigue	: using Modified Borg Scale (0 - 10 points) for each period evaluated warm-up (one minute of five minutes), exercise (minutes: 0-1'; 3-4'; 5-6'), and the recovery phase (minutes: 0-1'; 1-2'; 3-4'; 5-6';7-8';9-10') for both groups.	at 3 weeks. Outcome will be measured during the CWRET and will be carried out on different days, separate from approximately 7 days, for a total time frame of 3 weeks maximum per participant. Data will be collected during warm-up, exercise, and recovery
Heart rate	using a pulse oximetry for each period evaluated warm-up (one minute of five minutes), exercise (minutes: 0-1'; 3-4'; 5-6'), and the recovery phase (minutes: 0-1'; 1-2'; 3-4'; 5-6';7-8';9-10') for both groups.	at 3 weeks. Outcome will be measured during the CWRET and will be carried out on different days, separate from approximately 7 days, for a total time frame of 3 weeks maximum per participant. Data will be collected during warm-up, exercise, and recovery
Pulse oxygen saturation	using a pulse oximetry for each period evaluated warm-up (one minute of five minutes), exercise (minutes: 0-1'; 3-4'; 5-6'), and the recovery phase (minutes: 0-1'; 1-2'; 3-4'; 5-6';7-8';9-10') for both groups.	at 3 weeks. Outcome will be measured during the CWRET and will be carried out on different days, separate from approximately 7 days, for a total time frame of 3 weeks maximum per participant. Data will be collected during warm-up, exercise, and recovery
Respiratory rate	using a electrical impedance tomography for each period evaluated warm-up (one minute of five minutes), exercise (minutes: 0-1'; 3-4'; 5-6'), and the recovery phase (minutes: 0-1'; 1-2'; 3-4'; 5-6';7-8';9-10') for both groups.	at 3 weeks. Outcome will be measured during the CWRET and will be carried out on different days, separate from approximately 7 days, for a total time frame of 3 weeks maximum per participant. Data will be collected during warm-up, exercise, and recovery
Blood pressure	Using a sphygmomanometer and stethoscope will be evaluated at the beginning (basal), end of the exercise, and during the recovery phase by the same operator.	at 3 weeks. Outcome will be measured during the CWRET and will be carried out on different days, separate from approximately seven days, for a total time frame of 3 weeks maximum per participant. Data will be collected during the basal and recovery phase
Comfort scale associated with dispositive	using visual analog likert scale (0-5: 0: "nothing comfortable" to 5: "totally comfortable") evaluated before and at the end of the exercise.	at 3 weeks. Outcome will be measured during the CWRET and will be carried out on different days, separate from approximately 7 days, for a total time frame of 3 weeks maximum per participant. Data will be collected during the basal and end-exercise

Collaborators and Investigators

• Sponsor: Pontificia Universidad Catolica de Chile
• Investigators: Principal Investigator: Patricio Garcia, PhD(C), Departamento Ciencias de la Salud, Facultad de Medicina, Pontificia Universidad Católica de Chile.

Study record dates

Study Major Dates

• Study Start (Actual): July 25, 2022
• Primary Completion (Actual): September 13, 2022
• Study Completion (Actual): January 29, 2023

Study Registration Dates

• First Submitted: September 16, 2022
• First Submitted That Met QC Criteria: September 21, 2022
• First Posted (Actual): September 22, 2022

Study Record Updates

• Last Update Posted (Actual): December 7, 2023
• Last Update Submitted That Met QC Criteria: December 6, 2023
• Last Verified: September 1, 2022

More Information

Terms related to this study

• Keywords: Exercise; High-Flow Nasal Cannula; Electrical Impedance Tomography; Respiratory Physiology
• Other Study ID Numbers: 220510003

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: The investigators will evaluate IPD sharing since it is not intended a priori to perform an inferential analysis with statistics to evaluate the results before completing the study. In addition, it is a physiological study requiring only three days per subject (Approximately three weeks total) and with a low sample size.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No