A study of pulmonary function among Indians and assessment of the Wright peak flow meter in relation to spirometry for field use.

Abstract

The use of the Wright peak flow meter is becoming increasingly popular for a quick assessment of pulmonary function in the field (1-5). The instrument is portable, simple to use, and fairly accurate. Various difficulties in its use in hot humid environments and at high altitudes have been reported elsewhere (6). Nevertheless, the instrument has been found to be reliable and consistent in assessing over-all respiratory function. With the intention of introducing a small portable instrument for measuring respiratory function under difficult field conditions in developing tropical countries and mountainous areas, the present writers have tried to assess the value of the Wright instrument. Under such field conditions, its performance has been studied in 602 subjects (normal and diseased) of both sexes. The inter-relationship of the expiratory peak flow (EPF) has been compared with an accepted test, maximal breathing capacity (MBC). Correlation coefficients between 0.81 and 0.86 in male subjects have been reported by various workers (1-5) and a coefficient of 0.62 in 22 female subjects has been reported by Lockhart and associates ( 4). It is considered necessary to establish the closeness of correlation of EPF with other respiratory tests in Indian subjects who have varying levels of pulmonary function. Using these data an attempt has also been made to predict MBC from EPF and the reverse, for various age groups.