Functional Assessment and Pulmonary Rehabilitation: Challenges and Perspectives for Comprehensive Care

Overview

Individuals with Chronic Obstructive Pulmonary Disease (COPD) present with respiratory muscle dysfunction, characterized by reduced diaphragmatic contractility and mobility due to pulmonary hyperinflation, oxidative stress, and systemic inflammation. Effective assessment of diaphragmatic function is crucial for monitoring progress in pulmonary rehabilitation programs. This study aims to evaluate diaphragmatic function and mobility in COPD patients undergoing pulmonary rehabilitation with inspiratory muscle training, using ultrasound, and to identify associations between diaphragmatic dysfunction and clinical symptoms such as dyspnea and fatigue. A randomized clinical trial will be conducted to investigate the impact of rehabilitation on diaphragmatic function, correlating it with pulmonary function and physical performance.

Detailed description

This study aims to evaluate diaphragmatic muscle function and mobility through ultrasonography in individuals diagnosed with Chronic Obstructive Pulmonary Disease (COPD) undergoing a pulmonary rehabilitation program combined with inspiratory muscle training (IMT). The research will investigate the relationship between diaphragmatic behavior, clinical severity, and the repercussions on respiratory capacity.

Upon meeting the inclusion criteria, participants will undergo an initial clinical and sociodemographic assessment, including medical history, spirometry, manovacuometry, and the 6-Minute Walk Test (6MWT). Symptom impact and dyspnea will be measured using the COPD Assessment Test (CAT) and the mMRC scale. Participants will then be allocated into two groups:

IMT Group (IMTG): Participants will perform IMT using the PowerBreathe Classic (3 sets of 10 reps; load increasing from 50% to 60% of MIP), followed by resistance training (60-70% of 1RM) and aerobic training (20 minutes on a stationary bike at 60-80% intensity based on the Karvonen Formula and Borg Scale 4-6).

Control Group (CG): Participants will undergo the exact same resistance and aerobic training protocols as the IMTG. However, they will perform a Sham IMT using the device at its minimum load setting (3 sets of 10 reps) to maintain the same training volume and procedural consistency without the threshold training effect.

Interventions

• Device Pulmonary rehabilitation combined with inspiratory muscle training
  Rehabilitation will begin with diaphragmatic breathing and Inspiratory Muscle Training (IMT) with the Powerbreathe Classic device (3 sets of 10 repetitions, 1 min rest). The initial load will be 50% of PImáx, progressing 10% every 10 sessions until reaching 60%, with monitoring for fatigue and dyspnea. Resistance Training (RT) will utilize lat pulldown, bench press, and leg press on the weight training station. The load is based on the 1RM test, starting at 60% and progressing to 70% after 10 s
• Device Pulmonary rehabilitation with placebo inspiratory muscle training
  Pulmonary rehabilitation will consist of resistance and aerobic training protocols with the same specifications as the TMI Group. The placebo TMI will be performed on the Powerbreathe device with minimal load, consisting of 3 sets of 10 repetitions interspersed with 1 minute of rest.

Primary outcome measures

• Diaphragmatic Excursion (DE) [Time frame: Baseline and after 7 weeks.]

Secondary outcome measures (7)

• Diaphragmatic Thickness (Tdi) [Time frame: Baseline and after 7 weeks.]
• Diaphragmatic Thickening Fraction (DTF) [Time frame: Baseline and after 7 weeks.]
• Lung Function Parameters (Spirometry) [Time frame: Baseline and after 7 weeks.]
• Respiratory Muscle Strength (MIP and MEP) [Time frame: Baseline and after 7 weeks.]
• COPD Assessment Test (CAT) Score [Time frame: Baseline and after 7 weeks]
• Medical Research Council (MRC) Dyspnea Scale [Time frame: Baseline and after 7 weeks of intervention.]
• Functional Capacity (6-Minute Walk Test - 6MWT) [Time frame: Baseline and after 7 weeks.]

Eligibility criteria

Inclusion criteria

• Age 40 years or older.
• Both sexes are eligible (men and women).
• Clinically diagnosed COPD, clinically stable, classified in Stages I, II, III or IV of GOLD (Global Initiative for Chronic Obstructive Lung Disease).
• Ability to understand and provide the signed Informed Consent Form to participate in the study.

Exclusion criteria

• Physical limitations and/or cognitive impairment that prevent the execution of the study protocol.
• Currently engaged in physical therapy treatment and/or physical activity that may interfere with the study results.
• Presence of severe, uncontrolled, or disabling comorbidities.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Triple blind

Primary purpose

Treatment

Study locations

Brazil · 1 center

• Teaching and Assistance Unit in Physiotherapy and Occupational Therapy — Belém

Publications

• Neder JA, Andreoni S, Lerario MC, Nery LE. Reference values for lung function tests. II. Maximal respiratory pressures and voluntary ventilation. Braz J Med Biol Res. 1999 Jun;32(6):719-27. doi: 10.1590/s0100-879x1999000600007. PMID 10412550
• Spruit MA, Singh SJ, Garvey C, ZuWallack R, Nici L, Rochester C, Hill K, Holland AE, Lareau SC, Man WD, Pitta F, Sewell L, Raskin J, Bourbeau J, Crouch R, Franssen FM, Casaburi R, Vercoulen JH, Vogiatzis I, Gosselink R, Clini EM, Effing TW, Maltais F, van der Palen J, Troosters T, Janssen DJ, Collins E, Garcia-Aymerich J, Brooks D, Fahy BF, Puhan MA, Hoogendoorn M, Garrod R, Schols AM, Carlin B, B PMID 24127811
• Beaumont M, Mialon P, Le Ber C, Le Mevel P, Peran L, Meurisse O, Morelot-Panzini C, Dion A, Couturaud F. Effects of inspiratory muscle training on dyspnoea in severe COPD patients during pulmonary rehabilitation: controlled randomised trial. Eur Respir J. 2018 Jan 25;51(1):1701107. doi: 10.1183/13993003.01107-2017. Print 2018 Jan. PMID 29371379
• Troosters T, Janssens W, Demeyer H, Rabinovich RA. Pulmonary rehabilitation and physical interventions. Eur Respir Rev. 2023 Jun 7;32(168):220222. doi: 10.1183/16000617.0222-2022. Print 2023 Jun 30. PMID 37286219
• ATS Committee on Proficiency Standards for Clinical Pulmonary Function Laboratories. ATS statement: guidelines for the six-minute walk test. Am J Respir Crit Care Med. 2002 Jul 1;166(1):111-7. doi: 10.1164/ajrccm.166.1.at1102. No abstract available. PMID 12091180
• Santana PV, Cardenas LZ, Albuquerque ALP, Carvalho CRR, Caruso P. Diaphragmatic ultrasound: a review of its methodological aspects and clinical uses. J Bras Pneumol. 2020 Nov 20;46(6):e20200064. doi: 10.36416/1806-3756/e20200064. eCollection 2020. PMID 33237154
• Hayata A, Minakata Y, Matsunaga K, Nakanishi M, Yamamoto N. Differences in physical activity according to mMRC grade in patients with COPD. Int J Chron Obstruct Pulmon Dis. 2016 Sep 13;11:2203-2208. doi: 10.2147/COPD.S109694. eCollection 2016. PMID 27695306

Identifiers

NCT: NCT07415746 · 8.013.941

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗