ABSOLUTE HEMODILUTION CARDIOPULMONARY BYPASS - FREE WATER DISTRIBUTION AND PROTEIN MOBILIZATION IN BODY COMPARTMENTS

Water retention in the body compartments was studied in patients who underwent cardiopulmonary bypass with absolute hemodilution and blood replacement exclusively with nonhemic solutions. During operation, 3 1 2 volumes of fluid had to be administered for each volume of blood lost in order to maintain cardiovascular stability. Of this amount, 1 volume was excreted as urine and insensible water loss, 2 1 2 volumes were held in the body, 1 2 volume of it in the blood stream. The extravascular to intravascular partition ratio of retained water varied from 1 : 3 to 1 : 9. These figures are higher than those usually cited for compartmental equilibration of retained fluid following resuscitative therapy for hemorrhage. It is suggested that water distribution in patients subjected to open-heart surgery is influenced to an appreciable extent by ill-defined effects on the circulation by the mechanics of the bypass procedure itself. © 1969.