Clinical Values of Diaphragmatic Movement in Patients with Chronic Obstructive Pulmonary Disease

Background: Diaphragmatic movement affects dyspnea in the COPD patient.Research Question: Which of the diaphragm-related factors are closely related to Pulmonary Function test in the COPD patients? Study design and Methods: We enrolled 60 patients with COPD who attend respiratory outpatients. The diaphragm evaluation was performed using ultrasound, and PFT, 6MWT was performed in a respiratory outpatient clinic. Dyspnea scare, BMI, PFT, 6MWT and diaphragmatic factors collected and statistically analyzed. Results:In total patients, the right forced-excursion at supine positon was 6.9 ±2.000, left forced-excursion at supine position was 7.6 ±1.649. Right forced-excursion at supine position (p=0.003, R 2 =0.137), left forced-excursion at supine position (p=0.048, R 2 =0.074) and thickness of right end-expiratory (p=0.016, R 2 =0.094) were significantly associated with FEV1. When the group with right diaphragmatic excursion ≥ 6.7 was further divided into groups according to FEV1 (< 50% or ≥ 50%) , FEV1/FVC, MIP , portable peak flow meter, 6-minute walk distance, SpO2 before and after the 6MWT, and right diaphragmatic thickness at end-expiration subgroups were significantly different between the two groups. Interpretation: Right diaphragmatic forced excursion was closely related to FEV1, and analysis according to cut-off value which based on Right diaphragmatic forced excursion showed a large difference between groups. W hen the diaphragm function was maintained, MIP , portable peak flow meter, 6-minute walk distance, SpO2 before and after the 6 MWT, and right diaphragmatic thickness at end-expiration were different between the two FEV1 groups. Funding: None to declare. Declaration of Interest: None to declare. Ethical Approval: The study procedures were reviewed and approved by our institutional review board [IRB No. 05-2020-217].