High Flow Oxygen Therapy Effect on Healthy Subjects

Impact of High Flow Oxygen Therapy on Diaphragm Thickening Fraction in Healthy Subjects. A Prospective Cohort Study

The use of high-flow nasal cannula (HFNC) has increased. Diaphragmatic ultrasonography is a tool that, as a noninvasive complement to esophageal pressure (Pes) measurement, allows the evaluation of diaphragm function and reflects, through the diaphragm thickening fraction (DTf), the magnitude of diaphragmatic fiber recruitment. The objective of this study was to evaluate the impact of HFNC therapy on the DTf in healthy subjects. Second, this study aimed to assess the behavior of the respiratory rate (RR) and the work of breathing in these subjects.

Study Overview

• Status: Completed
• Conditions: Healthy Volunteers; Respiratory Rate; Diaphragm
• Intervention / Treatment: Device: High flow nasal canula

• Study Type: Interventional
• Enrollment (Actual): 13
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Argentina
  • Buenos Aires
    • Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina, 1280AED
      • Hospital Britanico de Buenos Aires

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• healthy subjects over 18 years old

Exclusion Criteria:

• contraindication for esophageal balloon placement
• diagnosis of lung disease
• smokers

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Non-Randomized
• Interventional Model: Single Group Assignment
• Masking: Single

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Diaphragm thickening fraction.	ultrasound measurements were performed by an expert operator (the same in all cases). The ultrasound measurement was performed using a high-resolution linear transducer in real-time in B-mode. The diaphragm thickness was measured at the end of expiration and the end of inspiration of the same ventilatory cycle and the average value of 3 ventilatory cycles was recorded. A 2-minute washout period was allowed between each test condition to avoid the summation of effects. The DTf and PTPes/min were calculated for each subject in each available condition (baseline - without flow- , wtih 20 and 40 liters per minute): DTf = End Inspiratory Diaphragm thickening - End Expiratory Diaphragm thickening / End Expiratory Diaphragm thickening x 100	Immediately after 5 min of each condition (baseline, 20 and 40 liters per minute) the diaphragmatic thickness was measured at the end of inspiration y de la expiration during 3 consecutive respiratory cycles (each cycle is between 3 and 10 seconds)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Respiratory Rate	The number of breaths per minute was recorded in 60 seconds.	The number of breaths per minute was recorded in 60 seconds.
Esophageal pressure swing (Pes).	Difference between basal Pes and maximum inspiratory Pes deflection.	5 minutes each condition
Esophageal pressure-time product per minute (PTPes/min).	It was calculated as the area determined by esophageal deflection multiplied by respiratory rate. An ad hoc software developed in MATLAB R2018b (The MathWorks, Inc. Massachusetts, United States) was used for this purpose.	Through study completion, an average of 24 weeks

Collaborators and Investigators

• Sponsor: Argentinian Intensive Care Society
• Investigators: Study Chair: Gustavo A Plotnikow, RT, Hospital Britanico de Buenos Aires

Study record dates

Study Major Dates

• Study Start (Actual): March 1, 2022
• Primary Completion (Actual): May 30, 2022
• Study Completion (Actual): June 30, 2022

Study Registration Dates

• First Submitted: September 29, 2023
• First Submitted That Met QC Criteria: October 11, 2023
• First Posted (Actual): October 17, 2023

Study Record Updates

• Last Update Posted (Actual): October 17, 2023
• Last Update Submitted That Met QC Criteria: October 11, 2023
• Last Verified: October 1, 2023

More Information

Terms related to this study

• Keywords: Respiratory rate; Work of breathing; High flow nasal canula; High flow nasal canula therapy; Diaphragm thickening fraction
• Other Study ID Numbers: CRIHB #1220 PRISA No. 6256

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES

Drug and device information, study documents

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