Abstract / Summary
Abstract Background Diaphragmatic dysfunction plays a central role in respiratory failure during acute exacerbations of chronic obstructive pulmonary disease (COPD). Transcutaneous electrical diaphragmatic stimulation (TEDS) has emerged as a potential modality to enhance respiratory muscle performance; however, its clinical impact in COPD exacerbations remains uncertain. Objective This study aimed primarily to evaluate the effect of adjunctive TEDS on diaphragmatic function and clinical outcomes in patients with severe acute exacerbation of COPD (AECOPD). A secondary exploratory objective was to assess whether baseline diaphragmatic ultrasound measurements were associated with progression to IMV. Methods This prospective randomized controlled study included 128 patients with severe COPD exacerbation admitted to the respiratory critical care unit. Patients were randomly assigned to receive either standard medical therapy alone (control group) or standard medical therapy in combination with TEDS (intervention group). Diaphragmatic function was assessed using ultrasound, including diaphragmatic excursion, thickness, and diaphragmatic thickening fraction (DTF). Arterial blood gases were measured at baseline and during follow-up. The primary analysis compared clinical and diaphragmatic outcomes between randomized treatment groups. Secondary exploratory analyses examined the associations between baseline clinical, gas-exchange, and diaphragmatic parameters and subsequent progression to IMV. Results TEDS was associated with a modest between-group improvement in diaphragmatic excursion, whereas differences in diaphragmatic thickness, DTF, progression to IMV, and major hospital outcomes were not statistically significant. In the secondary exploratory analysis, higher baseline PaCO₂, lower PaO₂/FiO₂, lower diaphragmatic excursion, and lower DTF were independently associated with progression to IMV. Progression to invasive mechanical ventilation occurred in 6/64 (9.4%) patients in the TEDS group and 12/64 (18.8%) patients in the control group; however, this numerical difference did not reach statistical significance ( p = 0.08). In multivariable logistic regression, treatment allocation was not independently associated with progression to IMV (adjusted OR = 0.82, 95% CI: 0.38–1.74; p = 0.60). DTF demonstrated an AUC of 0.83 for discriminating progression to IMV, while the combined DTF–PaCO₂ model demonstrated an AUC of 0.89. These exploratory associations and their discriminatory performance require validation in independent populations. Conclusion This randomized controlled trial did not demonstrate a statistically significant reduction in progression to invasive mechanical ventilation or improvement in major hospital outcomes with adjunctive TEDS. TEDS was associated with modest improvement in selected diaphragmatic parameters, particularly diaphragmatic excursion, while the prognostic value of baseline diaphragmatic dysfunction requires confirmation in larger, independently validated cohorts. Trial registration ClinicalTrials.gov identifier: NCT07020299.