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Unformatted text preview: hatics. If an imbalance occurs where net filtration exceeds the capacity of the lymphatics, then edema results. The kidneys are an exception to these generalizations in that renal glomerular capillaries filter large amounts of fluid along their entire length. This results from higher glomerular capillary hydrostatic pressures and higher capillary permeabilities. 5 Pulmonary Circulation Hydrostatic and Oncotic Pressures
Capillary Hydrostatic Pressure (PC )
This pressure drives fluid out of the capillary (i.e., filtration), and is highest at the arteriolar end of the capillary and lowest at the venular end. Depending upon the organ, the pressure may drop along the length of the capillary (axial pressure gradient) by 15-30 mmHg. The axial gradient favors filtration at the arteriolar end (where PC is greatest) and reabsorption at the venular end of the capillary (where PC is the lowest). The average capillary hydrostatic pressure is determined by arterial and venous pressures (PA and PV), and by the ratio of post-to-precapillary resistances (RV/RA...
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- Fall '07
- Hydrostatic Pressure