In a normal pleural space, fluid enters and exits at a constant equal rate because of the
ongoing filtration of a small amount of low-protein liquid in normal microvesselsNear
the end of the 19th century, Starling and Tubby1 hypothesized that the exchange of microvascular
fluid and solutes was governed by the balance between hydrostatic pressure,
osmotic pressure, and membrane permeability, and they devised the Starling equation