MEDizzy - Listed below are the hydrostatic and oncotic pressures

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The Circulation (I)

Listed below are the hydrostatic and oncotic pressures within a microcirculatory bed. Plasma colloid osmotic pressure = 25 mm Hg Capillary hydrostatic pressure = 25 mm Hg Venous hydrostatic pressure = 5 mm Hg Arterial pressure = 80 mm Hg Interstitial fluid hydrostatic pressure = −5 mm Hg Interstitial colloid osmotic pressure = 10 mm Hg Capillary filtration coefficient = 10 ml/min/mm Hg What is the rate of net fluid movement across the capillary wall?

ExplanationThe rate of net fluid movement across a capillary wall is calculated as capillary filtration coefficient × net filtration pressure. Net filtration pressure = capillary hydrostatic pressure − plasma colloid osmotic pressure + interstitial colloid osmotic pressure − interstitial hydrostatic pressure. Thus, the rate of net fluid movement across the capillary wall is 150 ml/min. Filtration rate = Capillary filtration coefficient (Kf) × Net filtration pressure Filtration rate = Kf × [Pc − Πc + Πi − PI] Filtration rate = 10 ml/min/mm Hg × [25 − 25 + 10 − (−5)] Filtration rate = 10 × 15 = 150 ml/min