Respiratory Muscle Fatigue at Different Breathing Modes

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

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.

Study Overview

• Status: Recruiting
• Conditions: Healthy
• Intervention / Treatment: Other: Square wave 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).

• Study Type: Interventional
• Enrollment (Anticipated): 12
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Denmark
  • Danmark
    • Aalborg, Danmark, Denmark, 9220
      • Recruiting
      • Mathias Krogh Poulsen
      • Contact: Mathias K Poulsen; Phone Number: 0045 28297625; Email: mkpo@hst.aau.dk

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 60 years (Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

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

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Single

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
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.	Up to two months between the two different breathing trials (randomized order)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
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).	Up to two months between the two different breathing trials (randomized order)
Tidal volume	Tidal Volume (ml) will be measured with a flowsensor (Hans Rudolph) through a pressure box (ICU lab, KleisTek)	Up to two months between the two different breathing trials (randomized order)
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)	Up to two months between the two different breathing trials (randomized order)
Ratings of perceived exertion	Borg Dyspnea Scale, from 0-10 where 0 is no effort at all and 10 is maximal breathing effort.	Up to two months between the two different breathing trials (randomized order)
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).	Up to two months between the two different breathing trials (randomized order)
Respiratory rate	Respiratory rate (breaths/min) will be measured with a flowsensor (Hans Rudolph) through a pressure box (ICU lab, KleisTek)	Up to two months between the two different breathing trials (randomized order)
Minute ventilation	Minyte ventilation (l/min) will be measured with a flowsensor (Hans Rudolph) through a pressure box (ICU lab, KleisTek)	Up to two months between the two different breathing trials (randomized order)
Insp. and expiratory time	Insp. and expiratory time (s) will be measured with a flowsensor (Hans Rudolph) through a pressure box (ICU lab, KleisTek)	Up to two months between the two different breathing trials (randomized order)

Collaborators and Investigators

• Sponsor: Aalborg University

Study record dates

Study Major Dates

• Study Start (Actual): October 1, 2021
• Primary Completion (Anticipated): December 1, 2022
• Study Completion (Anticipated): December 1, 2022

Study Registration Dates

• First Submitted: April 21, 2022
• First Submitted That Met QC Criteria: May 24, 2022
• First Posted (Actual): May 26, 2022

Study Record Updates

• Last Update Posted (Actual): May 26, 2022
• Last Update Submitted That Met QC Criteria: May 24, 2022
• Last Verified: May 1, 2022

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Fatigue
• Other Study ID Numbers: Eso_pres_fatigue

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

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