Hyperoncotic albumin solutions are used to restore plasma volume in the context of resuscitation in intensive care units, but their kinetic properties in critically ill patients subject to trauma and inflammation are largely unknown.
A population fluid volume kinetic model was developed to determine whether the clinical efficacy of 20% albumin and its duration of action were affected following surgery.
The colloid fluid was administered intravenously at a rate of 3ml/kg over 30 minutes to a group of 15 patients undergoing major abdominal surgery, and the ensuing body fluid shifts were compared to those occurring in a control group of 15 healthy individuals.
An increase in plasma albumin occurring after 10 minutes of infusion resulted in a two-fold increase in plasma volume expansion due to the absorption of non-circulating fluid, which in turn diluted albumin plasma levels and increased capillary leakage of albumin.
No significant differences in the kinetics of the infused fluid were observed between the groups. In addition, age and arterial blood pressure, inflammation markers or evidence of endothelial glycocalyx shedding did not affect the elimination of the volume of infused albumin.
In summary, this analysis showed stable and sustained plasma volume expansion in both post-surgical patients and healthy individuals.