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The utility of alternative spirometry measurements and the variability of each for assessing bronchodilator response

The utility of pulmonary function parameters in addition to FEV1 (forced expiratory volume in one second) and FVC (forced vital capacity) and the variability of each for assessing the reversibility of airway obstruction in adults undergoing bronchodilator response testing

Status
Recruiting
Phases
Unknown
Study type
Interventional
Source
ANZCTR
Registry ID
ACTRN12616000603415
Enrollment
800
Registered
2016-05-10
Start date
2016-05-02
Completion date
2020-05-01
Last updated
2020-01-13

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

None listed

Brief summary

This is an observational study of human participants recruited in their capacity as consumers of health or disability support services and their informed consent will be obtained. Patients already performing a bronchodilator response test as part of their clinical care will be recruited, This test assesses the reversibility of any airway obstruction present and current international guidelines for determining what constitutes a significant response to a bronchodilator are not well informed. Patients will perform the test as per laboratory protocol with additional slow and less strenuous manoeuvres added. Patients will also rate their level of breathlessness before and after being given the inhaler (bronchodilator) and complete a questionnaire on respiratory symptoms and medications, the scores of which will be correlated with the degree of change in each pulmonary function parameter. The testing session will be repeated on patients who volunteer to extend their appointment on the same day or return within one week of their initial visit. Those returning on another day will be given a placebo inhaler (single-blinded) to assess the placebo or expectancy effect of bronchodilator administration on spirometry and self-reported measures of breathlessness. This study aims to quantify the natural, short-term variability of spirometry in a representative sample of respiratory patients by obtaining repeated spirometry measurements from patients attending the Respiratory Physiology Laboratory. This variability data will be used to create confidence limits for the spirometric parameters and this will determine the change that is required in these parameters to confirm reversibility of airway obstruction. This study will also determine whether alternative spirometry parameters, other than those currently recommended by international guidelines, may better detect a significant bronchodilator response in some patient subgroups.

Interventions

Participants will rate their current level of breathlessness and perform slow spirometry manoeuvres in addition to the forced spirometry manoeuvres that have been requested as part of their clinical care. A forced spirometry manoeuvre is a complete inspiration, followed by a maximal effort, sharp, complete expiration, and is completed by a fast and full inspiration. A slow spirometry manoeuvre is the same sequence of breathing without using maximal force. Where time permits, this sequence will b

Participants will rate their current level of breathlessness and perform slow spirometry manoeuvres in addition to the forced spirometry manoeuvres that have been requested as part of their clinical care. A forced spirometry manoeuvre is a complete inspiration, followed by a maximal effort, sharp, complete expiration, and is completed by a fast and full inspiration. A slow spirometry manoeuvre is the same sequence of breathing without using maximal force. Where time permits, this sequence will be repeated after a 30 minute wait. The repetition of this sequence is additional to the patient's standard care. As part of standard clinical care spirometry will then be repeated 15 minutes after administration of 400mcg Salbutamol via a metered dose inhaler and spacer. The patient's level of breathlessness will be reassessed at this point. Participants will also answer two short respiratory questionnaires. Total standard testing time is 45 minutes and the additional manoeuvres will add approximately 15 minutes to the appointment time, making total participation one hour. The questionnaires will not add time to the appointment as they will be answered during the standard 15 minute wait time after bronchodilator administration. If the patient volunteers to perform repeat testing after a 30 minute wait, this will add a further 40 minutes to their session, making the visit 1 hour and 40 minutes in total.

Sponsors

Laura Ploen
Lead SponsorIndividual

Study design

Allocation
Non-randomised trial
Intervention model
Other
Primary purpose
Diagnosis
Masking
Blinded (masking used) (Subject)

Eligibility

Sex/Gender
All
Age
18 Years to 95 Years
Healthy volunteers
Yes

Inclusion criteria

Aged 18 - 95 years. Having a bronchodilator response test as part of their visit to the respiratory laboratory. Able to provide informed consent.

Exclusion criteria

Patient has an absolute contraindication to performing spirometry. This includes: recent mycardial infarction, recent eye or thoracic surgery, or any other condition deemed by the testing scientist to put the patient at risk. Patient is unable to perform acceptable spirometry.

Outcome results

None listed

Source: ANZCTR · Data processed: Feb 4, 2026