HETEROGENEOUS DISTRIBUTION OF PULMONARY VENTILATION IN INTENSIVE-CAREPATIENTS DETECTED BY FUNCTIONAL ELECTRICAL-IMPEDANCE TOMOGRAPHY

Electrical impedance tomography (EIT) is a new noninvasive imaging tec hnique which utilizes the different electrical properties of biologica l tissues to produce cross-sectional images of selected parts of the b ody. When applied on the thorax, the cyclic fluctuations of electrical impedance of the lung tissue, associated with different air contents of the lungs in the course of the respiratory cycle, can be used to ge nerate derived EIT tomograms which represent the spatial distribution of ventilation in the chosen transverse plane. The corresponding evalu ation technique, the functional EIT, was used for the first time to fo llow the regional ventilation in three intensive care patients. The me thod was shown (1) to identify; the redistribution of inspired air in the lungs associated with controlled ventilation in a patient undergoi ng elective laparotomy,, (2) to follow the improvement of locally impa ired lung ventilation in the course of severe pneumonia, and (3) to de tect regional reduction of ventilation due ti, lobar atelectasis with stasis pneumonia in a patient with bronchial carcinoma.