Constant plasma volume and colloid osmotic pressure after infusion of albumin 20%: A secondary analysis

Aberrant elimination patterns after intravenous infusion of albumin 20% may predispose to persistent vascular overload or hyper-oncoticity. In the present report, the frequency of deviating elimination patterns was studied by visual examination followed by calculations of the volume and albumin kinetics over 5 hours in 86 volunteers and clinical patients who received 3 mL/kg albumin 20% over 30 min (mean, 231 mL). Constant and virtually unchanged plasma volume expansion (i.e., steady state) developed after 21% of all infusions and developed most often during surgery (64%) but rarely in volunteers (3%). The subsequent kinetic analysis associated such steady state with slow capillary filtration (-27% vs. all others, p < 0.01). Steady state or a gradual increase of the plasma oncotic pressure occurred in 28% and was characterized by fast turnover of fluid, which taken together resulted in a dehydrating effect. By contrast, steady state for plasma albumin was associated with a 48% lower capillary leakage rate constant for albumin (p < 0.001) as compared to the other experiments. In conclusion, steady state for plasma volume and increasing colloid osmotic pressure after infusion of albumin 20% was more dependent on variations in fluid kinetics than on albumin kinetics.