Intravenous administration of crystalloid or colloid solutions is frequently employed to correct hypovolemia in intensive care unit patients. In critical illness, particularly sepsis and severe trauma, there is an increase in vascular wall permeability, leading to the trans-endothelial escape of serum albumin, which is the principal oncotic plasma constituent. This phenomenon provokes hypoalbuminemia and edema formation. 

The volume effects of intravenous human albumin are more than the crystalloid solutions. If hypoalbuminemia moderates this effect, the crystalloid-to-albumin ratio of fluid resuscitation volumes needs to be better characterized. Randomized controlled trials have shown that intravenous administration of human albumin solutions for volume resuscitation causes a lower net fluid balance compared with crystalloids, and lesser infusion volumes may be adequate for hemodynamic stabilization when human albumin solutions are employed. 

The present study summarizes the current evidence and conclusions drawn regarding the role of hypoalbuminemia in volume resuscitation. ′Saline versus Albumin Fluid Evaluation′ study used 4% human albumin solution or saline and found the saline-to-albumin ratio of study fluids to be significantly higher in patients with baseline serum albumin concentrations of </=25 g/L contrasting patients with baseline serum albumin concentrations of >25 g/L. In patients receiving renal replacement therapy, intravenous administration of 20–25% human albumin solution relieves intradialytic hypotension and improves fluid removal better than saline if serum albumin levels are equally reduced. 

These data indicate that hypoalbuminemia is an effect moderator in volume resuscitation and plasma expansion with albumin solution. The volume effectiveness of intravenous human albumin solution in resuscitation is greater when the serum albumin levels are low. In clinics, serum albumin concentrations per se may guide when and how to include intravenous albumin in fluid resuscitation if greater amounts of crystalloids are required, which warrants further studies.

Wiedermann CJ. Moderator Effect of Hypoalbuminemia in Volume Resuscitation and Plasma Expansion with Intravenous Albumin Solution. International Journal of Molecular Sciences. 2022; 23(22):14175. https://doi.org/10.3390/ijms232214175