Maximal inspiratory and expiratory pressures in men with chronic obstructive pulmonary disease: A cross-sectional study

Abstract

Introduction: Respiratory muscle dysfunction is a cardinal feature in chronic obstructive pulmonary disease (COPD) contributing to decreased exercise capacity and pulmonary function test (PFT) limitation with progression of the disease. Maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) are reliable parameters for assessing the respiratory muscle strength. Aims: This study aims to measure maximal inspiratory and expiratory pressures in male COPD patients, to determine their correlates, and to study the relationship between the severity of COPD and respiratory muscle strength. Patients and Methods: This was an observational, cross-sectional study. A total of 100 males, who were known COPD patients and who were clinically stable, were recruited. Both inpatients and outpatients were studied. Spirometric PFT test was done, and MIP and MEP were measured using respiratory pressure meter. Descriptive statistics and Pearson's correlation were used. Results: The mean (± standard deviation) MIP and MEP were 47.73 (±19.6) cm H2O and 60.76 (±11.6) cm H2O, respectively. MIP and MEP showed a highly significant correlation (P < 0.001) with forced expiratory volume at 1 s (FEV1) and forced vital capacity. The correlation of MIP and MEP with FEV1shows a positive linear trend, and the MEP values were higher than MIP values. There was a decrease in MIP and MEP with increasing severity of COPD. Conclusion: MIP decreases with progression of the disease, and thus, inspiratory muscle training should be included in a pulmonary rehabilitation program.

Keywords

• Chronic obstructive pulmonary disease
• maximal expiratory pressure
• maximal inspiratory pressure
• pulmonary function test