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Respiratory Muscle Fatigue at Different Breathing Modes

Primary Purpose

Healthy

Status

Recruiting

Phase

Not Applicable

Locations

Denmark

Study Type

Interventional

Intervention

Square wave breathing

About this trial

This is an interventional basic science trial for Healthy

Eligibility Criteria

18 Years - 60 Years (Adult)All SexesAccepts Healthy Volunteers

Inclusion Criteria:

Healthy men or women
Age ≥18 and ≤60 years
BMI ≥ 20 and ≤30

Exclusion Criteria:

Drug addiction defined as the use of cannabis, opioids or other drugs
Previous and present neurologic (e.g. ataxia), musculoskeletal (e.g. muscular dystrophy) or mental illnesses (e.g. schizophrenia)
History of mechanical ventilation, COVID-19 with respiratory complications, lung cancer
Part of lung resected
Presence of dyspepsia/heart-burn/abdominal pain
Presence of esophageal varices
Presence of liver disease
Presence of esophageal hernia
Pregnancy
Failure to comply with transcranial magnetic stimulation adult safety screen
History of epilepsy, metal implants in head or jaw
Acute or chronic lung diseases, e.g. asthma, COPD, bronchitis etc.
Lack of ability to cooperate

Sites / Locations

Mathias Krogh PoulsenRecruiting

Outcomes

Primary Outcome Measures

Time to task failure (Tlim)

The time (s) from the subject starts to breathe under the experimental condition, and until task failure will be measured. Task failure is defied by either subject intolerance to continue or by lacking ability of the subject to maintain the target pressure and/or timing. From a previous publication (Bellemare and Grassino, JAP, 1982), it is estimated that subjects will reach Tlim between 30min to 1 hour. If breathing is continued after 1 hour, task failure will not happen as breathing can be continued indefinitely.

Secondary Outcome Measures

Respiratory muscle pressures

Respiratory muscle pressure will be measured by esophageal and gastric pressure (in cmH2O) using a naso gastric catheter fitted with double balloons (Nutrivent) connected to a pressure sensor (ICU lab, KleisTek).

Tidal volume

Tidal Volume (ml) will be measured with a flowsensor (Hans Rudolph) through a pressure box (ICU lab, KleisTek)

Respiratory work

Work of breathing (j), will be calculated from outcome measure 2 and 9 (pressure (cmH2O) and insp. and expiratory time (s)). Measured with pressure box (ICU lab, KleisTek)

Ratings of perceived exertion

Borg Dyspnea Scale, from 0-10 where 0 is no effort at all and 10 is maximal breathing effort.

Metabolism

Energy expenditure calculated from VO2 (ml/min) nad VCO2 (ml/min) with e.g Weir equation. VO2 and VCO2 are measured with Beacon (Mermaid care).

Respiratory rate

Respiratory rate (breaths/min) will be measured with a flowsensor (Hans Rudolph) through a pressure box (ICU lab, KleisTek)

Minute ventilation

Minyte ventilation (l/min) will be measured with a flowsensor (Hans Rudolph) through a pressure box (ICU lab, KleisTek)

Insp. and expiratory time

Insp. and expiratory time (s) will be measured with a flowsensor (Hans Rudolph) through a pressure box (ICU lab, KleisTek)

Full Information

NCT ID

NCT05393115

First Posted

April 21, 2022

Last Updated

May 24, 2022

Sponsor

Aalborg University

1. Study Identification

Unique Protocol Identification Number

NCT05393115

Brief Title

Respiratory Muscle Fatigue at Different Breathing Modes

Official Title

Does Inspiratory Pressure Wave Form Influence Respiratory Muscle Fatigue and Metabolism During Resistive Breathing

Study Type

Interventional

2. Study Status

Record Verification Date

May 2022

Overall Recruitment Status

Recruiting

Study Start Date

October 1, 2021 (Actual)

Primary Completion Date

December 1, 2022 (Anticipated)

Study Completion Date

December 1, 2022 (Anticipated)

3. Sponsor/Collaborators

Responsible Party, by Official Title

Principal Investigator

Name of the Sponsor

Aalborg University

4. Oversight

Studies a U.S. FDA-regulated Drug Product

Studies a U.S. FDA-regulated Device Product

Data Monitoring Committee

5. Study Description

Brief Summary

The study aims at investigating if time to respiratory muscle fatigue and metabolism are influenced by the pressure wave form mode applied during resistive breathing.

Detailed Description

In healthy subjects fitted with a nasogastric double balloon catheter and breathing at a resistance, the investigators will measure time to failure, Borg ratings, VO2, VCO2, flow, esophageal-, gastric- and airway-pressure. This will be done during breathing at either a square wave or triangle wave pressure waveform, in random order and trials separated by >two days. Further respiratory muscle fatigue will be investigated pre and post intervention by maximal esophageal pressure generation (voluntary and with cervical magnetic stimulation).

6. Conditions and Keywords

Primary Disease or Condition Being Studied in the Trial, or the Focus of the Study

Healthy

7. Study Design

Primary Purpose

Basic Science

Study Phase

Not Applicable

Interventional Study Model

Crossover Assignment

Masking

Participant

Allocation

Randomized

Enrollment

12 (Anticipated)

8. Arms, Groups, and Interventions

Intervention Type

Other

Intervention Name(s)

Square wave breathing

Other Intervention Name(s)

Triangle wave breathing

Intervention Description

difference in time to failure from the two breathing modes

Primary Outcome Measure Information:

Title

Time to task failure (Tlim)

Description

Time Frame