Slope-Ratio(SR) Analysis in Maximal Expiratory Flow Volume Curve

Kim, Joon Woo; Kim, Young Whan; Yu, Bin; Shim, Young Soo; Kim, Keun Youl; Han, Yong Chol

doi:1986.33.2.110

Tuberc Respir Dis > Volume 33(2); 1986 > Article

Original Article

Tuberculosis and Respiratory Diseases 1986;33(2):110-115.
DOI: https://doi.org/10.4046/trd.1986.33.2.110 Published online June 1, 1986.

Slope-Ratio(SR) Analysis in Maximal Expiratory Flow Volume Curve

Joon Woo Kim, Young Whan Kim, Bin Yu, Young Soo Shim, Keun Youl Kim, Yong Chol Han

Department of Internal Medicine Medical College of Seoul National University

최대호기유량용적곡선에서의 Slope-Ratio(SR)에 관한 연구

김준우, 김영환, 류빈, 심영수, 김건열, 한용철

Abstract

There are numerous parameters for the detection of obstructive airway disease in Maximal Expiratory Flow Volume Loop(Curve). Slope-Ratio(SR) is another new parameter which considered to be useful for the detection of early small airway dysfunction using both MEF ₅₀ and MEF _75• SR was measured in 3 groups of subjects(50 person in each group) and obtained the following results. 1) SR of first group, who have normal limit values of FVC, FEV_1.0, MEF ₅₀, MEF₇₅, was 0.86土 0.24. 2) SR of second group, who have less then 70% predicted MEF ₇₅ but all normal FVC, FEV_1.0, MEF ₅₀, showed 1.30土0.15 3) SR of third group, who have less than 70% predicted MEF ₅₀, FEV_1.0, was 1. 38 土 0.19. 4) Arbitrary value of SR 1.0 appeared to be the marginal value of Small Airway Dysfunction(SAD) in functional aspect. 5) Further SR analysis among the evident obstructive airway disease patients will be needed for the clinically useful parameter.