Transvascular fluid distribution of hyperoncotic Dextran solution.

Purpose: The purpose of this study was to confirm the changes in extra-aand intravascular fluid distribution during an i.v. influsion of hyperoncotic Dextran solution.

Methods: Twenty-three mongrel dogs with normal capillary integrities were divided into four groups. The R1 and R2 groups received i.v. infusion of Ringer lactate (RL) with a rate of 10 and 30 ml·kg·h, the D group 6% Dextran 70 solution (DEX) of 10 ml·kg·h. and the RD group DEX of 10 plus RL of 20 ml·kg·h. The distribution of infused fluid was assessed with the changes in circulating blood volume (CBV), extravascular fluid volume (EVW), and thoracic duct lymph volume (QL).

Results: In the R1 and R2 groups, EVW increased by 63% and 51%, respectively, of total infusion volume (tInf), while CBV increased by only 10% and 13% of tnf. In the D and RD groups, CBV increased by 103% and 51% of tInf. However, EVW decreased by 21% and increased by 32% of tInf, respectively. In the latter groups, the plasma volume filtered out into the extravascular compartment was less than in the corresponding former group by 52% and 6% of tInf, respectively and the restoration ratio of EVW by lymph was about 3 to 1.8 times greater.

Conclusion: One-fourth to one-third of the plasma expanding effect of 6% Dextran 70 solution was ascribed to direct fluid drawing from the extravascular space, and the rest was due to both the decrease in plasma filtration into extravascular space and the increase in lymphatic restoration of EVW.