Hydrostatic Pulmonary edema with fluid in alveoli is usually seen when PCWP is -
Ans. is 'd' i.e., >25 mm Hg o Normally a constant fluid exchange takes place between the pulmonary! vascular bed and the interstitium of the lung.o Fluid that extravasates at the start of the capillary bed (transudate) is reabsorbed due to the intravascular colloid osmotic (oncotic) pressure or is drained off by lymphatic vessels.o Pulmonary edema develops when fluid extravasation outstrips reabsorption by the capillaries and exceeds the drainage capacity of the lymphatics.o The rate of fluid reabsorption is determined by the intravascular and interstitial oncotic pressure.o The normal pulmonary capillary pressure is 8-12 mm Hg and the normal oncotic pressure of the plasma is approximately 25 mm Hg.o This pressure differential ensures the complete reabsorption of the fluid when the hydrostatic intravascular pressure (pulmonary capillary pressure) rises and approaches 18-25 mmHg intersitial edema occurs initially and alveolar edema develops at higher pressures > 25 mm Hg.Note:o Pulmonary> edema may result from damage to the alveolar capillary> membrane or from fall in the oncotic pressure.o Alveolar Pulmonary edema from elevated hydrostatic pressure (Cardiosenic) is npicallv associated with PCWP > 25 mm Hg. Elevated PCWP but with Pressure < 25mm Hg is usually associated with intestitialpulmonary edema and not true alveolar pulmonary edema.PCWPStageInterpretation in relation to Hydrostatic Pulmonary Edema5-12 mm Hg (Normal)NormalNo Pulmonary Edema12-17 mm HgStage 1Excess fluid can still be cleared by lymphatic drainage X-ray-cephalisation of pulmonary vessel18-25 mm Hg (Moderate Increase)Stage 2Characterized by the presence of interstitial edema Some fine cracking breath sounds may X-ray kereley B lines, suppleural efffusion>25mmHg (Severe Increase)Stage 3Characterized by alveolar pulmonary edema (fluid and proteins enter the alveolar space) due to rupture alveolar membrane Physical findings are prominent and include clinically significant hyproxemia,tachypnea, respiratory distress, diffuse crackles, and wheezing breath sounds X-ray- pulmonary edema (infiltrates and vascular engorgement)
>6mmHg
0mmHg
15mmHg
25mmHg
Respiratory