Efficacy of ambroxol hydrochloride combined with respiratory function training in stable COPD: CT, pulmonary function, and blood gas-based evaluation

Background Chronic obstructive pulmonary disease (COPD) is a progressive condition requiring comprehensive management. The efficacy of ambroxol hydrochloride combined with respiratory function training in stable COPD patients remains to be fully evaluated using multidimensional assessments including chest CT visual scoring. Methods This retrospective investigation encompassed individuals diagnosed with stable COPD (GOLD grade I–III) admitted to our hospital between November 2023 and November 2025. Patients were assigned to a monotherapy group (ambroxol hydrochloride alone) or a combination group (ambroxol hydrochloride plus respiratory function training). Chest CT visual scores (emphysema severity score [ESS] and airway wall thickening score [AWTS]), pulmonary function indices (FEV 1 , FVC, FEV 1 /FVC, FEV 1 %pred, PEF), arterial blood gas parameters (PaO 2 , PaCO 2 , SaO 2 , pH, HCO 3 − ), serum inflammatory biomarkers (CRP, IL-6, IL-8), mMRC dyspnea score, CAT score, 6-min walking distance, clinical efficacy, acute exacerbations, and adverse events were assessed before and after the 3-month treatment period. Results A total of 150 patients were analyzed (monotherapy group, n = 68; combination group, n = 82). After treatment, the combination group showed significantly greater improvements in ESS (P = 0.002) and AWTS (P = 0.015). FEV 1 , FVC, FEV 1 %pred, and PEF were significantly enhanced, and all blood gas parameters improved (all P < 0.05). Serum CRP, IL-6 and IL-8 levels were markedly reduced (P < 0.05). Combination group also achieved better mMRC, CAT, and 6MWD outcomes, a higher overall response rate (90.24% vs. 73.53%), and a lower annual exacerbation rate (P < 0.05), while adverse events did not differ between groups. Conclusion Adding respiratory function training to ambroxol hydrochloride significantly improves pulmonary function, blood gas status, inflammation, symptoms, and chest CT visual scores in stable COPD patients, with a favorable safety profile.