[Red cell mass and plasma volume in chronic cor pulmonale (author's transl)].

Red cell mass and plasma volume were simultaneously measured by Cr51 and J125-albumine, respectively, in 36 patients with chronic obstructive lung disease and cor pulmonale. Additionally, pulmonary function tests and arterial blood gas analyses as well as pulmonary circulatory and right ventricular hemodynamic measurements were performed the same day. Patients were divided into 3 clinical subgroups: 1. a predominantely emphysematous A-type (n =12), 2. a predominantly bronchial B-type (n = 12), and 3. an intermediate type (n = 12) with about equal scores for A and B. With regard to the cardiac state, A-patients were clinically characterized by small ptotic hearts on chest x-ray and the absence of overt cardiac failure during the whole course of illness whereas B-patients generally showed radiological evidence of heart dilatation associated with recurrent episodes of manifest right ventricular failure. Patients of the intermediate type mostly had recovered from cardiac failure. The following results were obtained: 1. Red cell volume, plasma volume, and total blood volume were within normal limits in A-patients and in patients of the intermediate type. A marked hypervolemia in B-patients was almost entirely due to an increased red cell volume. 2. Close correlations of the red cell volume and total blood volume, respectively, to the arterial PO2 as well as to the arterial PCO2 could be established. 3. Total blood volume was significantly correlated to certain hemodynamic parameters, including cardiac output, stroke volume, pulmonary artery pressure, and right ventricular enddiastolic pressure. 4. The quotient body hematocrit/venous hematocrit was lowered to a significant degree as compared to normal subjects. As a consequence, indirect determination of red cell volume and total blood volume from plasma volume and venous hematocrit leads to a consistent overestimation of both parameters, amounting to 28% in the mean for the red cell mass and to 12% for the total blood volume in the present series.