Circulating blood volumes in pulmonary hypertension associated with erythrocytosis--the effects of therapeutic hemodilution.
In the Eisenmenger syndrome, indirect estimation of blood volumes may provide quite inaccurate information when seeking to define therapeutic strategies. With this in mind, we analyzed directly the red cell mass, plasma volume, and total blood volume in patients with pulmonary hypertension associated with congenital cardiac defects and erythrocytosis, comparing the results with the respective estimated volumes, and examining the changes induced by therapeutic hemodilution. Thus, we studied 17 patients with the Eisenmenger syndrome, aged from 15 to 53 years, in the basal condition, studying 12 of them both before and after hemodilution. We also investigated five individuals with minimal cardiac lesions, aged from 14 to 42 years, as controls. Red cell mass and plasma volumes were measured using [51chromium]-sodium chromate and [131iodine]-albumin respectively. Hemodilution was planned so as to exchange 10% of the total blood volume, using 40,000 molecular weight dextran simultaneously to replace the removed volume. The mean values of the red cell mass, plasma volume and total blood volume as assessed by radionuclide techniques were 32%, 31% and 32% higher than the respective volumes as estimated using empirical mathematical formulas (p < 0.002). The measured total blood volume was also 19% higher in the patients compared with controls. Following a period of 5 days after hemodilution, we noted a 13% reduction in red cell mass (p = 0.046), and 10% reduction in total blood volume (p = 0.02), albeit with no changes in the plasma volume. We conclude that direct measurement of blood volumes is useful for proper management of these patients, and provides results that are considerably different from those obtained by empirical estimations.
Department of Pediatric Cardiology, Adult Congenital Heart Disease, Heart Institute, São Paulo, Brazil.
Rilvani C
RC
Gonçalves
Carlos Alberto
CA
Buschpigell
Antonio Augusto
AA
Lopes
D000293:Adolescent; D000328:Adult; D001810:Blood Volume; D004541:Eisenmenger Complex / Q000628:therapy*; D004911:Erythrocyte Volume; D005260:Female; D006438:Hemodilution / Q000379:methods*; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D010953:Plasma Volume; D016896:Treatment Outcome