"Crystalloids are thought to counteract that movement via the osmotic pressure exerted by their solutes, whereas colloids are designed to exploit oncotic pressure gradients for the same effect." ...

Colloid Solution: A fluid containing larger insoluble molecules, such as albumin, which helps to maintain oncotic pressure and vascular integrity.

Generalized edema is often a feature of heart failure, when the hydrostatic pressure in the blood vessels rises. In conditions such as nephrotic syndrome and liver failure, the oncotic pressure ...