From: A Rational Approach to Perioperative Fluid Management Anesthes. 2008;109(4):723-740. doi:10.1097/ALN.0b013e3181863117 Figure Legend: Fig. 3. The classic description of vascular barrier functioning in arterioles and capillaries, according to Ernest Starling (schematic): An inward-directed colloid-osmotic (= oncotic) pressure gradient is opposed to an outward-directed hydrostatic pressure of fluid and colloids. The arrows symbolize the small net fluid filtration assumed according to this model. The extremely simplified illustration does not consider the postulated small net fluid reabsorption on the venular site suggested by this model, due to an assumed decrease in the hydrostatic and an assumed increase in the oncotic pressure gradient. The Starling equation is mentioned in the main text. ΠI= oncotic pressure in the interstitial space; ΠV= oncotic pressure in the vascular lumen; EC = endothelial cell; PV= hydrostatic pressure in the vascular lumen; PI= hydrostatic pressure in the interstitial space. Date of download: 11/13/2017 Copyright © 2017 American Society of Anesthesiologists. All rights reserved.