Evaluation of pulmonary function and neurophysiological change in patient with chronic obstructive pulmonary disease / 中华物理医学与康复杂志

ABSTRACT

Objective To explore the association between the lung function and the related electroneurophysiological parameters in patients with chronic obstructive pulmonary disease (COPD). Methods Fifty COPD patients were studied. The lung function and the phrenic motor nerve conduction (PNC) were examined, respectively. Thirty cases of non respiratory disorders served as control. The lung function tests included maximal voluntary ventilation (MVV%), forced vital capacity (FVC), force expiratory volume (FEV 1) and RV/TLC% (residual volume, RV; total lung capacity, TLC). The phrenic nerve was stimulated electrically at the midpoint of the posterior border of the sternomastoid muscle, and the diaphragmatic compound muscle action potential (dCMAP) was recorded between the 7th and 8th intercostal space and xiphoid process. Results The relative values of MVV%, FVC 1/FVC 1% and RV/TLC% were 49.6?18.8, 62.5?16.4 and 54.1?8.0, respectively, which was significantly lower than that expected. There was no significant difference with regard to the PNC latency between the patients and the controls. The dCMAP amplitude ratio in the COPD patients was significantly lower than that of the controls, i.e., the dCMAP amplitude decreased in the COPD patients. Conclusion The decreased dCMAP might be associated with abnormal lung function. The PNC examination would provide valuable information for the evaluation of diaphragmatic dysfunction in those with abnormal lung function.