[The breathing pattern and inspiratory drive in chronic obstructive pulmonary disease].

Quantitative analysis of breathing pattern in 20 cases of COPD patients and 15 normal persons showed a significant correlation between values of VT/TI and P0.1; VT/TI value may be used clinically as an index of inspiratory drive. The elevation of VT/TI values of COPD patients at the end of high CO2-rebreathing denoted the sensitivity of their respiratory center is still preserved. However, the impairment of respiratory muscle endurance in hypercapnic COPD patients under rebreathing stress showed a prolongation of TI/TT.