Role of Intrapleural Pressure in the Positional Effect on Gas Exchange in Unilateral Pleural Effusion

Han, Dong Cheol; Uh, Soo Taek; Ahn, Byung Soo; Kim, Taek Jun; Park, Choon Sik

doi:1984.31.4.176

Tuberc Respir Dis > Volume 31(4); 1984 > Article

Original Article

Tuberculosis and Respiratory Diseases 1984;31(4):176-182.
DOI: https://doi.org/10.4046/trd.1984.31.4.176 Published online December 1, 1984.

Role of Intrapleural Pressure in the Positional Effect on Gas Exchange in Unilateral Pleural Effusion

Dong Cheol Han, Soo Taek Uh, Byung Soo Ahn, Taek Jun Kim, Choon Sik Park

Department of lnternal Medicine, College of Medicine, SoonChun Hyang University

편측성 늑막삼출환자에서 체위 변동에 따른 동맥혈 가스분압 변화와 늑막압과의 상관관계에 관한 연구

한동철, 어수택, 안병수, 김태준, 박춘식

Abstract

The positional effect on gas exchange is diminished in a large unilateral pleural effusion presumable because of decrease in perfusion and decreased changes in ventilation-perfusion mismatching. We measured intrapleural pressure(Plp) and estimated the volume of effusion(PHt) by measuring height of meniscus on chest P-A in 24 patients with unilateral tuberculous pleural effusion and one patient witn nephrotic syndrome to study the relative role of Plp and PHt in the positional effect of effusion on gas exchange. Plp and PHt were positively correlated(r=0.66, p<0.005). Positional PaO₂ differece(Δ paO₂) was inversely correlated to PHt(r = -0. 50, p < 0.05). ΔPaO₂ was also inversely correlated to Plp but the correlation was not statistically significant(r= -0. 4, P>0.05). The results of this study suggest that intrapleural pressure may be important but that other factors may also be responsible for the positional effect on gas exchange in unilateral effusion .