A Study on the Distribution of Body Fluids after Rapid Saline Expansion in Normal Subjects and in Patients with Renal Insufficiency: Preferential Intravascular Deposition in Renal Failure

Abstract
The effect of rapid i.v. infusion of 25 ml of isotonic NaCl solution/kg body weight on extracellular fluid volume (ECFV, 82Br distribution volume), plasma volume (131I-labeled albumin distribution volume) and blood volume (from plasma volume and packed cell volume) was studied in 9 normal subjects and a group of 11 patients with end-stage renal disease (ESRD). Immediately after the infusion, the increases in ECFV were equal in the 2 groups but the increases in plasma and blood volumes were significantly larger in the patients with ESRD. Ninety minutes after the end of the infusion, the blood volume/ECFV ratio was significantly decreased from the control value in the normal subjects, but slightly increased in the patients with ESRD. In severe renal failure the control of fluid distribution may be changed in a way which leads to a preferential distribution of rapidly infused saline into the intravascular compartment.