Study on the Application of Combined Electrical Stimulation of Diaphragm and Abdominal Muscles in Pulmonary Rehabilitation of Patients with Stable Chronic Obstructive Pulmonary Disease

A BSTRACT Objective: This study aimed to assess the safety and clinical efficacy of respiratory neuromuscular electrical stimulation as an adjunct to pulmonary rehabilitation in patients with severe and very severe chronic obstructive pulmonary disease (COPD) during the stable phase. Methods: A total of 52 patients with severe to very severe COPD were randomly assigned to either the experimental group or the control group. The experimental group received respiratory-synchronized electrical stimulation of both the diaphragm and abdominal muscles, while the control group received diaphragm-only stimulation. Both interventions were administered daily at a frequency of 40 Hz for 30 min per session over a continuous 4-week period. Safety and efficacy were comprehensively evaluated in both groups. Results: The improvement in the 6-min walk distance (6MWD) was significantly greater in the experimental group compared to the control group. Post-treatment, the 6MWD in the experimental group and control group was 540.44 ± 62.04 meters and 487.44 ± 51.49 meters, respectively, showing a statistically significant difference ( P < 0.01). Intra-group analyses revealed significant increases in 6MWD from baseline in both groups ( P < 0.001). Both groups also showed marked improvements in modified Medical Research Council (mMRC) dyspnea scores, arterial oxygen saturation, and pulmonary function parameters, including forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), and FEV1% predicted ( P < 0.05), although no significant differences were observed between the groups ( P > 0.05). No significant differences were found in arterial blood gas parameters or diaphragm mobility between the groups at the end of the treatment period ( P > 0.05). Conclusion: Respiratory-synchronized combined electrical stimulation of the diaphragm and abdominal muscles significantly improves exercise capacity, as measured by 6MWD, compared to diaphragm-only stimulation in patients with severe to very severe COPD. Both treatments were safe and demonstrated improvements in clinical outcomes, with the combined approach providing superior benefits in physical endurance.