What are the commonly used plasma substitutes in clinical practice?

Plasma substitutes, also known as plasma extenders, are colloidal solutions made of naturally processed or synthesized macromolecules, which can replace plasma to expand blood volume, that is, the molecular weight and colloid osmotic pressure are similar to plasma proteins, which can be in the circulation for a long time, maintain an appropriate concentration and not accumulate in the body. It will not cause red blood cell aggregation obstacles, and incision bleeding and other adverse reactions, the product is non-antigenic and lethal, and is harmless to the body.

Commonly used clinically include dextran, hydroxyethyl starch and gels.

1. Dextran, 6% dextran isotonic saline solution is a commonly used polysaccharide plasma substitute. Its osmotic pressure is high and can be maintained in the body for 6 to 12 hours. It is often used in the preparation stage of blood volume shock to replace plasma.

2. Hydroxyethyl starch is a plasma substitute made of corn starch. It has been used as a common finished dosage forms for volume expansion in volume therapy and surgery for hypovolemic shock.

3. The gels is a plasma substitute composed of various gelatin and electrolytes. Its osmotic pressure reaches 6.2 kPa, which can effectively increase plasma volume and prevent tissue edema, so it is beneficial to venous return and improves cardiac output and peripheral tissue perfusion. It also causes the relative viscosity to be similar to that of plasma, so it has the effect of plasma dilution, improving microcirculation and accelerating blood flow rate.