Diaphragmatic Dysfunction across the COPD Continuum: From Pathophysiology to Rehabilitation and Mechanical Ventilation

Abstract

Chronic obstructive pulmonary disease (COPD) remains a leading cause of morbidity and mortality worldwide, frequently diagnosed at advanced stages and often accompanied by significant extrapulmonary complications. Amongst these, diaphragmatic dysfunction plays a central yet often underrecognized role in disease progression, respiratory failure, and poor clinical outcomes. This review synthesises current evidence on diaphragmatic dysfunction in COPD and mechanically ventilated (MV) patients, evaluates diagnostic techniques, and explores therapeutic interventions, particularly pulmonary rehabilitation.  A structured literature search of PubMed, Scopus, and Web of Science was conducted between January 2000 and March 2026. Two independent reviewers screened titles, abstracts, and full texts against predefined eligibility criteria. Studies addressing diaphragmatic dysfunction in patients with COPD or MV were included. Findings were synthesised narratively and supplemented by the GOLD 2026 report. No formal risk of bias assessment was performed, consistent with narrative review methodology. Diaphragmatic dysfunction in COPD is characterised by muscle fibre atrophy, fibre-type shifting, hyperinflation-induced shortening, and reduced force-generating capacity, leading to dyspnea, respiratory failure, and increased mortality. Diagnostic approaches include transdiaphragmatic pressure measurement (gold standard), ultrasound, chest radiography, computed tomography (CT), Magnetic resonance imaging (MRI), and fluoroscopy. Pulmonary rehabilitation improves diaphragmatic strength, exercise tolerance, dyspnea, and quality of life. GOLD 2026 supports home-based and tele-rehabilitation as effective alternatives to centre-based programs. However, significant barriers persist, including underdiagnosis, insufficient funding, limited provider awareness, and inequitable access to rehabilitation services. Diaphragmatic dysfunction is an important yet underdiagnosed complication of COPD and MV. Early recognition using appropriate diagnostic tools, combined with targeted rehabilitation, can improve functional outcomes. Future research should optimise stimulation techniques, standardise tele-rehabilitation protocols, and expand evidence to post-exacerbation and multimorbid populations.