Heterogeneous ventilation and perfusion: a sensitive indicator of lung impairment in nonsmoking coal miners.

Abstract

Twenty life-long nonsmoking West Virginia coal-miners participated in a study to amplify the role of focal irregularities on regional ventilation (V) and perfusion (Q) and to develop an improved method for the early detection of coal-workers' pneumoconiosis. Their mean age was 59.3 yr and they averaged 35.2 years' exposure to coal dust. Conventional pulmonary function tests were supplemented by measurement of V, Q and lung volume (V), using radioactive Kr-81m, Tc-99m MAA and Xe-127, respectively, to determine regional abnormalities in lung function. A computer analysis of the regional distributions of V/V, Q/V and V/Q was performed, and their topographical distributions and indices of heterogeneity (HI) computed. V/V and Q/V were significantly reduced in the lower third, and increased in the upper two-thirds of the miners' lungs; V/Q was reduced in the upper half. The miners' V/V and Q/V were more heterogeneous (p less than 0.001) than that of eleven age-matched controls, with mean ventilation HI values of 0.190 +/- 0.027 and 0.133 +/- 0.011, respectively, and mean perfusion HI values of 0.206 +/- 0.022 and 0.164 +/- 0.041, respectively. P(A-a)O2 correlated positively (r = 0.72; p less than 0.001) with ventilation HI. Gas exchange was the most significant functional measurement, being abnormal in 19/20 subjects. In contrast, conventional spirometric measurements were within the predicted normal limits in all but four miners.

• Authors: H Susskind, J C Acevedo, J Iwai, D L Rasmussen, D K Heydinger, H R Pate, W H Harold, A B Brill
• Journal: The European respiratory journal (Eur Respir J) Vol. 1 Issue 3 Pg. 232-41 (Mar 1988) ISSN: 0903-1936 [Print] England
• PMID: 3384076 (Publication Type: Journal Article, Research Support, U.S. Gov't, Non-P.H.S.)

Topics

• Adult
• Aged
• Coal Mining
• Female
• Humans
• Image Processing, Computer-Assisted
• Male
• Middle Aged
• Pneumoconiosis (diagnostic imaging, physiopathology)
• Radionuclide Imaging
• Respiratory Function Tests
• Smoking (physiopathology)
• Spirometry
• Ventilation-Perfusion Ratio