Maintenance of oncotic pressure

Oncotic pressure (also called colloid osmotic pressure) describes the osmotic pressure exerted by plasma proteins, especially albumin, within capillaries. It functions to draw water back into the circulation from tissues, counteracting hydrostatic pressure, and thus maintains fluid distribution, vascular volume, and prevents edema. Albumin contributes the greatest portion to plasma oncotic pressure due to its abundance and chemical properties. Clinically, loss of oncotic pressure (from low albumin or protein loss) results in fluid shifts from the blood into tissues, causing swelling (edema) and potentially compromising blood volume and pressure. Maintenance of oncotic pressure is therefore critical to circulatory and tissue fluid homeostasis, but it is not itself a molecular target. Therapeutic strategies to restore oncotic pressure include administration of albumin, management of underlying disease, and use of diuretics.

Other names

colloid osmotic pressure maintenancefluid balance via oncotic pressure

Albumin: increases plasma oncotic pressure, pulls water into the vasculature; Diuretics: increase urine output, decrease interstitial fluid