EFFECT OF DEXTRAN ON BLOOD-VOLUME AND INTERACTIONS WITH VOLUME REGULATORY SYSTEMS

The effect of 800 ml 3% dextran Ringer's lactate on blood volume was studied in two groups of young surgical patients who had no significant blood loss during operation. One group was normovolaemic, the other was made hypovolaemic by rapid withdrawal of 600 ml blood. A third group, with neither blood loss nor volume administration, served as the control. The main finding was a restoration of the initial blood volume within 48 h of the dextran infusion in normovolaemic subjects and a maintenance of the resituted volume in hypovolaemic subjects. The plasma dextran concentration showed an identical decay in both situations. Total plasma albumin increased in the hypovolaemic group towards the value before bleeding within 24 h, whereas in the normovolaemic group, it decreased progressively after dextran infusion with significant falls after 24 and 48 h. This suggests that the homeostatic mechanisms are based mainly on the discrepant behaviour of albumin in the two volume situations. For the assessment of volume effect of exogenous colloids, the interaction with blood volume regulatory mechanisms should be taken into account. Furthermore, the actual volume situation and the albumin reserves have to be considered. © 1979 Springer-Verlag.