None listed
Conditions
Brief summary
To quantify inspiratory muscle endurance, through the Fatigue Resistance Index method, in healthy people. Poor respiratory muscle endurance is a consequence of invasive mechanical ventilation for patients in intensive care (1,2). Over the past 10 years, researchers including ourselves (2,3) have used the ‘Fatigue Resistance Index’ (FRI) method to quantify the endurance of the respiratory muscles of intensive care patients. This involves inhaling through a hand-held device for 2 seconds, then breathing against resistance for 2 minutes, and then inhaling maximally through the hand-held device again. The FRI is a feasible alternative to more complex invasive methods of analysing diaphragmatic endurance. However, to our knowledge, this method of quantifying endurance has not been tested in a normal population. Following our publication in 2015 (1), we wish to measure FRI in normal healthy subjects to allow us to compare our data from intensive care patients with age and gender matched healthy participants. REFERENCES: 1. Bissett B, Ledtischke IA, Boots R & Paratz J. Weaned but weary: one third of adult intensive care patients mechanically ventilated for 7 days or more have impaired inspiratory muscle endurance after successful weaning. Heart and Lung. 2015; 44: 15 – 20. 2. Chang AT, Boots RJ, Brown MG, Paratz J, Hodges PW. Reduced inspiratory muscle endurance following successful weaning from prolonged mechanical ventilation. Chest. 2005; 128: 553 – 559. 3. Bissett BM, Leditschke IA, Paratz JD, Boots RJ. Protocol: inspiratory muscle training for promoting recovery and outcomes in ventilated patients (IMPROVe): a randomised controlled trial. BMJ Open. 2012:2e000813.
Interventions
To quantify inspiratory muscle endurance, through the Fatigue Resistance Index method, in healthy people in a one off session. The procedure is identical to that performed in the previous studies in intensive care at Canberra Hospital. To perform the testing, participants will need to ‘empty their lungs’, then inhale maximally through a hand-held device (MircoRPM Respiratory Pressure Metre) for 1 to 2 seconds. This will be repeated 3 times to ensure reliability. The participant will then breathe
To quantify inspiratory muscle endurance, through the Fatigue Resistance Index method, in healthy people in a one off session. The procedure is identical to that performed in the previous studies in intensive care at Canberra Hospital. To perform the testing, participants will need to ‘empty their lungs’, then inhale maximally through a hand-held device (MircoRPM Respiratory Pressure Metre) for 1 to 2 seconds. This will be repeated 3 times to ensure reliability. The participant will then breathe through an inspiratory muscle trainer (Threshold IMT) for 2 minutes at a resistance equivalent to 30% of their maximum effort. The participant will then repeat the 3 maximum inhalations through the hand-held MicroRPM machine. Thus a total of 6 maximal breaths is required for testing, i.e. 3 breaths either side of the 2 minute resistance challenge. Participants will be monitored closely and testing ceased if not tolerated at any point. Total testing time should take less than 15 minutes allowing for explanation and rest time.
Sponsors
Elizabeth Kilpatrick
Eligibility
Sex/Gender
All
Age
20 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
Healthy adults, with no known respiratory disease, who have not undertaken any form of inspiratory muscle training. Healthy adults who are able to communicate and provide consent to perform testing.
Exclusion criteria
Participants will be excluded it they already suffer from lung disease (eg Chronic Obstructive Lung Disease, Asthma or Cystic Fibrosis). These pathologies are likely to affect the strength and endurance of inspiratory muscles, and would therefore contaminate the sample of healthy participants. Participants will also be excluded if they already participate in any form of inspiratory muscle training as this is likely to affect the Maximal Inspiratory Pressure manoeuvre used in the FRI test, and would not represent usual respiratory muscle activity for a healthy person (i.e. they are likely to have supra-normal results). Participants will be excluded if they cannot communicate sufficiently to provide consent or perform testing.
Outcome results
None listed