Muscle strength in people with COPD undergoing bronchoscopy lung volume reduction combined with pulmonary rehabilitation: a pilot study

MARCELO COERTJENS ^1,2* Patricia Xavier Chaves ³ Gilberto Sampaio Santos Barbosa ¹ Willian Assunção de Sousa Santos ³ Mathieu Gruet ⁴ Hugo Goulart De Oliveira ⁵ Marli Maria Knorst ⁶ Leonardo Alexandre Peyré-Tartaruga ⁷

• ¹ Programa de Pós-Graduação em Ciências Biomédicas, Universidade Federal do Delta do Parnaiba, Parnaiba, Brazil
• ² Programa de Pós Graduação em Ciências do Movimento, Universidade Federal do Piauí, Teresina, Brazil
• ³ Curso de Fisioterapia, Universidade Federal do Delta do Parnaiba, Parnaiba, Brazil
• ⁴ IAPS Unité de recherche, Université de Toulon, La Garde, Provence-Alpes-Cote d Azur, France
• ⁵ Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
• ⁶ Programa de Pós-Graduação em Ciências Pneumológicas, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
• ⁷ University of Pavia, Pavia, Lombardy, Italy

Background: We hypothesized that optimization of lung mechanics by bronchoscopic lung volume reduction (BLVR) using endobronchial valves favors pulmonary rehabilitation (PR) and increases muscle strength in people with COPD (pwCOPD). We aimed to assess whether BLVR combined with PR in pwCOPD results in an increase in muscle strength in the quadriceps, upper limbs, and respiratory muscles. Methods: This is a before-after study consisting of 16 pwCOPD (Gold III-IV) who were divided into a valve and control group. All participated in 20 PR sessions consisting of high-intensity interval training on a cycle ergometer and resistance training. The mMRC dyspnea scale and muscle strength outcomes were assessed: quadriceps maximal voluntary isometric contraction (MVIC), hand grip strength (HGS), number of repetitions of elbow flexion (EF), maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP). The effects on group, time, and interaction were analyzed using GEE (α = 0.05). Results: Despite the reduction in pulmonary hyperinflation and dyspnea, the valve group showed no significant differences compared with control after PR in MVIC (35.5 ± 3.5 vs 36.1 ± 2.5 kg), EF (33.0 ± 3.3 vs 45.4 ± 6.8 repetitions), MIP (79.6 ± 7.1 vs 77.1 ± 5.0 cmH2O), and MEP (92.3 ± 8.0 vs 93.5 ± 9.2 cmH2O), while control group showed higher values in HGS (p < 0.05). Conclusions: The improvements in respiratory outcomes observed in the valve group had no additional effect on muscle strength when BLVR was combined with PR. Future studies using BLVR should consider a longer period of training after endobronchial valve insertion when analyzing muscle strength.