Dyspnea
Conditions
Keywords
Dyspnea perception, COPD, Exacerbations, CO2 rebreathing test
Brief summary
The perception of breathlessness varies significantly among COPD patients with similar severity of airflow limitation; those with poorer perception report less exacerbations as compared to those with frequent exacerbations. Cross-sectional comparison of breathlessness perception in COPD patients with frequent exacerbations or without frequent exacerbations. To assess Breathlessness Perception the investigators will increase the ventilatory demand of the patients by CO2-rebreathing method.
Detailed description
The perception of breathlessness varies between individuals. This is a well-established concept in asthma, but mostly unexplored in COPD; the relationship between airflow limitation (FEV1, % ref.) and breathlessness (mMRC) is weak. The perception of breathlessness varies significantly among COPD patients with similar severity of airflow limitation; those with poorer perception report less exacerbations as compared to those with frequent exacerbations. It is a cross-sectional comparison of breathlessness perception in COPD patients with frequent exacerbations (≥2 or ≥1 with hospitalization in the previous year) or without frequent exacerbations (0 or 1 without hospitalization in the previous year). To assess Breathlessness Perception the investigators will increase the ventilatory demand of the patients by CO2-rebreathing method. CO2 rebreathing test will be conducted to evaluate the acute ventilatory response to CO2 inhalation used to estimate central chemoreceptor responsiveness in patients with the obstructive pulmonary disease. Simple descriptive statistics (unpaired T-test) and correlation analysis (bivariate and multivariate) will be used to analyze results.
Interventions
PROCEDURESpirometry
Before re-breathing (if the patient not performed one 6 months in advance).
PROCEDURECO Exhaled breath
In current smokers of both arms to confirm that the patient has not smoked in the past three hours and to asses the smoking status (heavy, moderate, light).
PROCEDUREP01
P01 is the negative airway pressure generated during the first 100 ms of an occluded inspiration. It's an estimation of the neuromuscular drive to breathe.
PROCEDUREFeNO
The measurement of fraction of exhaled nitric oxide during exacerbations of COPD is higher than normal.
Sponsors
Hospital Clinic of Barcelona
Study design
Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
DIAGNOSTIC
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 80 Years
Healthy volunteers
No
Inclusion criteria
* patients with diagnosis of COPD (Gold 2 or 3 or 4) * \>2 months from last exacerbation and no change in therapy
Exclusion criteria
* patients on regular sedative drugs * patients with neuromuscular diseases * patients with respiratory failure and/or in long-term oxygen therapy
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| The negative airway pressure generated during the first 100 ms of an occluded inspiration, which is an estimation of the neuromuscular drive to breathe. (P01 ) | Baseline |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Borg scale | Baseline | 10-point subjective scoring system, in which a patient rates his/her effort of exertion. |
| Fractional exhaled nitric oxide (FeNO) | Baseline | — |
| Inspiratory capacity (IC) | Baseline | The sum of inspiratory reserve volume and tidal volume. |
| Ventilation at rest | Baseline | — |
| CO exhaled test | Baseline | Testing for Carbon Monoxide in exhaled breath in current smokers. |
Countries
Spain
Outcome results
None listed