Answer is D (>25mm Hg): Alveolar Pulmonary edema from elevated hydrostatic pressure (Cardiogenic) is typically associated with PCWP >25 ntm Hg. Elevated PCWP but with Pressure <25mm Hg is usually associated with interstitial pulmonary edema and not true alveolar pulmonary edema. Hydrostatic pulmonary edema is also known as cardiogenic pulmonary edema (since it typically arises from left hea failure). The inefficient left ventricle causes blood to back up in the *pulmonary circulation, increasing hydrostatic pressure in the pulmonary capillaries (Increased PCWP). High capillary pressure progressively forces fluid first into the interstitium (Interstitial Pulmonary Edema) and then into the alveoli (Alveolar Pulmonary Edema). Three stages of pulmonary edema can be distinguished based on the degree of fluid accumulation Stage 1 is characterized by excess fluid that can still be cleared by lymphatic drainage. Stage 2 is characterized by the presence of interstitial edema. Stage 3 is characterized by alveolar pulmonary edema (fluid and proteins enter the alveolar space) PCWP Stage Interpretation in relation to Hydrostatic Pulmonary Edema 6-12 mm Hg Normal No Pulmonary Edema (Normal) 12-18mm Hg Stage I Usually not associated with pulmonary edema (Mild Increase) Excess fluid can still be cleared by lymphatic drainage No Physical or X-ray Findings are usually evident 18 - 25 mm Hg Stage 2 Characterized by the presence of interstitial edema (Moderate Increase) Some physical findings including some fine crackling breath sounds may be evident X-ray evidences of pulmonary edema in the form of engorged pulmonary vessels and appearance of infiltrates may be seen >25 mm Hg Stage 3 Characterized by alveolar pulmonary edema (fluid and proteins enter the alveolar (Severe Increase) space) Physical findings are prominent and include clinically significant hypoxemia, tachypnea, respiratory distress, diffuse crackles, and wheezing breath sounds Obvious x-ray evidence of pulmonary edema (greatly increased infiltrates and vascular engorgement)