This study aims to i) assess the short-, mid- and long-term effectiveness of a patient-centred community-based pulmonary rehabilitation (PR) programme during during acute exacerbations of chronic obstructive pulmonary disease (AECOPD); ii) establish the minimal clinical important differences for PR in AECOPD for clinical and patient-reported outcome measures; and iii) evaluate patients' perspectives and self-reported impact of the PR programme.

Patients with AECOPD will be recruited via clinicians at hospitals and primary care centres. Sociodemographic, anthropometric and clinical data; vital signs and peripheral oxygen saturation; symptoms (dyspnoea, fatigue, cough and sputum); lung function; physical activity level; peripheral muscle strength; functional status; exercise tolerance; impact of the disease and health-related quality of life will be collected within 24h-48h of the AECOPD diagnosis. Then, patients will be randomly allocated to either conventional treatment or conventional treatment plus PR. After 3 weeks, all outcome measures will be reassessed. Additionally, follow-ups at 2, 6 and 12 months will be performed through phone calls to assess the number of recurrent AECOPD, healthcare utilization and mortality.

Conventional treatment will consist on daily medical treatment prescribed by the physician (i.e., medication).

Community-based PR will involve 6 sessions (2 times per week) of breathing retraining and airway clearance techniques, exercises for thoracic mobility, expansion and flexibility, cardiorespiratory exercise training, education and psychosocial support.

It is expected that, by including PR in the treatment of patients with AECOPD, they will express greater improvements in a shorter period of time and experience a decrease number of re-exacerbations and healthcare utilization.

Acute exacerbations of COPD (AECOPD) negatively impact on patients' health status and disease progression, and increase patients' susceptibility to exacerbations, hospitalizations and death. Therefore, the treatment goals for patients with AECOPD are to minimize the negative impact of these events and prevent their recurrence.

Pulmonary rehabilitation (PR) is the comprehensive intervention presenting the most well-established benefits in patients with stable COPD, thus, it would seem reasonable to consider PR as a management strategy for AECOPD. However, studies assessing PR role during AECOPD have shown conflicting results.

Therefore, the main aim of this project is to assess the short-, mid- and long-term effectiveness of a patient-centered community-based PR programme during AECOPD. Secondarily, we aim to develop and implement a community-based PR programme for patients with AECOPD, specifically tailored to their self-reported and clinical needs; establish the minimal clinical important differences for PR in AECOPD for clinical and patient-reported outcome measures; and evaluate patients' perspectives and self-reported impact of the PR programme.

A pilot study was performed between November 2016 and December 2017 to allow sample size calculation and adjustments to the protocol of the randomized controlled trial. Based on this pilot study, a sample size estimation was performed for the COPD Assessment Test to detect a moderate effect size (f=0.30), with 80% power, 5% significance level and moderate correlation among repeated measures (r=0.25). The minimum sample size estimation was 36 participants. However, as in respiratory interventions dropout rates are around 30-35%, a total of 50 participants with AECOPD will be needed.

The plan is to recruit approximately 50 voluntary patients with AECOPD via clinicians at hospitals and primary care centres. This study will enroll adult patients diagnosed with AECOPD according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria.

Patients will be recruited via the clinicians, who will provide a brief explanation about the study and inform the researcher about interested participants. Then, the researcher will contact interested participants and provide further information about the study, clarify any doubts and collect the inform consents. Patients will be eligible if they are: i) diagnosed with AECOPD according to the GOLD criteria; ii) included within 24-48h of the diagnostic; and iii) able to provide informed consent. Exclusion criteria will include: i) need for hospitalization; ii) other coexisting chronic respiratory diseases; iii) unstable cardiovascular disease; iv) musculoskeletal or neuromuscular conditions that preclude the performance of the assessments and/or treatment sessions; v) signs of cognitive impairment; vi) current neoplasia or immunological disease and vii) any therapeutic intervention in addition to standard of care.

Patients who agree to participate will be randomly allocated to the conventional treatment group (control group) or the conventional treatment plus PR group (experimental group).

Baseline data will be collected within the first 24-48 hours of the diagnosis of AECOPD. The researcher will collect sociodemographic, anthropometric and clinical data (e.g., number of exacerbations in the previous year); vital signs and peripheral oxygen saturation; symptoms (dyspnoea, fatigue, cough and sputum); lung function (spirometry); physical activity level; peripheral muscle strength (handgrip and hand-held dynamometer); functional status; exercise tolerance; impact of the disease and health-related quality of life.

Patients in the control group will receive daily medical treatment prescribed by the physician (i.e., medication).

Patients in the experimental group will receive daily medical treatment plus a community-based PR programme that will involve 6 sessions (2 times per week). The PR programme will consist of breathing retraining and airway clearance techniques, exercises for thoracic mobility, expansion and flexibility, cardiorespiratory exercise training, education and psychosocial support. This programme will be adjusted to each individual needs. After this period all measurements will be repeated. Furthermore, vital signs, peripheral oxygen saturation, dyspnoea and fatigue will also be collected before/during/after each session to monitor the intervention. Sessions will be conducted in properly equipped rooms or at patients' home and will last approximately 60 minutes.

Additionally, after 2, 6 and 12 months, the researcher will contact all participants via phone calls to collect data about the number of recurrent AECOPD, healthcare utilization (e.g., unscheduled visits, hospitalizations) and mortality.

Data analysis will be undertaken using Statistical Package for the Social Sciences (SPSS) software and will include descriptive and inferential statistics. To analyse changes in outcome measures, data from baseline and after treatment assessments will be compare. Moreover, between group comparisons will also be performed for baseline, after intervention and follow-ups assessments. Effect sizes for the interventions will also be calculated.

Inclusion Criteria:

• clinical diagnosis of AECOPD according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria (i.e., an episode of acute worsening of respiratory symptoms that result in additional therapy);
• included within 24-48h of the diagnostic;
• able to provide their own informed consent.

Exclusion Criteria:

• need for hospitalization;
• other coexisting chronic respiratory diseases;
• unstable cardiovascular disease;
• presence of musculoskeletal or neuromuscular conditions that preclude the performance of any of the assessments or the participation in the treatment sessions;
• signs of cognitive impairment;
• current neoplasia or immunological disease;
• any therapeutic intervention in addition to standard of care.