Plasma volume changes after infusion of various plasma expanders.

Area of Science:

• Anesthesiology
• Critical Care Medicine
• Pharmacology

Background:

• Intravenous fluid administration is crucial in post-operative care to maintain hemodynamic stability.
• Various plasma expanders, including colloids and crystalloids, are used to restore intravascular volume.
• Understanding the comparative efficacy and effects of different plasma expanders is essential for optimal patient management.

Purpose of the Study:

• To compare the plasma volume expansion efficacy of dextran 70, hydroxyethylstarch, polygelatin, albumin, and saline.
• To evaluate the impact of these expanders on plasma protein concentrations and total circulating protein mass.
• To determine the most suitable plasma expander for immediate post-operative fluid resuscitation.

Main Methods:

• Administration of 1 liter of colloid solution or saline intravenously in the immediate post-operative period.
• Measurement of plasma volume expansion and total plasma protein concentration in different patient groups.
• Calculation of total circulating protein mass following fluid infusion.

Main Results:

• Plasma volume expansion ranged from 790 to 180 ml, with dextran 70 being the most effective, followed by hydroxyethylstarch.
• Polygelatin and saline showed insufficient volume restitution despite higher infusion volumes.
• Albumin increased total protein concentration, while other expanders caused dilution; total circulating protein mass remained stable across groups.

Conclusions:

• Dextran 70 is the most efficient plasma volume expander, with hydroxyethylstarch as a comparable alternative for volume expansion.
• Dextran 70 offers additional benefits for microcirculation, making it preferable over hydroxyethylstarch due to unexplored metabolic pathways of the latter.
• Albumin is advantageous based on secondary effects like plasma protein patterns; polygelatin and saline are inadequate for rapid hypovolemia correction.