An Indian study of postural variation in peak expiratory flow rates in healthy, adult, male participants

Abstract

Background Peak expiratory flow rate (PEFR) reflects the strength and condition of respiratory muscles and the degree of airflow limitation in large airways. PEFR showing postural variation that follows a specific pattern in asthmatics and healthy individuals has been identified. Adequate data are not available for postural variation in normal individuals who are students of professional courses with a sedentary lifestyle. Lung volumes in normal individuals were significantly higher in the standing position. Some studies have reported that in healthy participants spirometric indices were higher while standing in comparison with the sitting position, whereas other studies have reported no differences between spirometric values obtained in the lying, sitting and standing positions. Hence, this study was undertaken to study the postural variation in PEFRs in healthy, adult, male participants in south India. Materials and methods PEFR was recorded in 50 adult, healthy, male participants aged 18–23 years who were students of professional courses. Mini Wright’s peak flow meter was used to measure the PEFR. Three readings were taken in the standing and lying positions. The best of the three recordings was considered as the final value. Results PEFR was decreased while lying down compared with standing in the participants studied, and the quantum of difference was noted. Conclusion With postural changes, the PEFR significantly differs on the basis of whether the measurements are taken in the standing or in the lying posture in healthy participants. The effect of posture may be of importance in recording PEFR, and changing to a better posture may be especially useful for those with weak expiration.