ABSTRACT
A colloid fluid contains large molecular weight particles. The semipermeable membrane of the healthy vasculature is relatively impermeable to such particles. The number of particles in the colloid solution promotes the retention of sodium and water around the core of the particle within the vascular space. Depending on the colloid oncotic pressure of the solution (COP), some colloid solutions can also draw fluid into the intravascular space from other fluid compartments in the body. 1 Colloid fluids can be categorized as either natural or synthetic. Natural colloids include whole blood with plasma proteins, plasma, and concentrated albumin solutions. 2 Synthetic colloids include dextran-70, oxypolygelatin, hydroxyethyl starch, and pentastarch. Colloid solutions are useful during the treatment of conditions associated with hypovolemic and septic shock, vasculitis, hypoproteinemia, and third-spacing of fluids such as pleural and peritoneal effusions and peripheral edema. 1
