Introduction Fluid accumulation in air spaces and parenchyma of the lungs leads to impaired gas exchange and may cause respiratory failure Pathophysiology edema arises due to an imbalance in hydrostatic and/or oncotic pressure increased hydrostatic pressure in the pulmonary capillaries (Pc) login to view 1 more bullet decreased oncotic pressure in the pulmonary capillaries (πc) login to view 1 more bullet movement of fluid is driven by Starling forces Causes changes in pressure are of cardiogenic or non-cardiogenic origin cardiogenic causes include heart failure login to view 3 more bullets in all cases above, an increase in left ventricular end diastolic volume increases hydrostatic pressure in LV, LA, pulmonary vein, and pulmonary capillaries login to view 2 more bullets non-cardiogenic causes include infection login to view 2 more bullets aspiration login to view 2 more bullets drugs login to view 1 more bullet high altitude ARDS login to view 1 more bullet Presentation Symptoms dyspnea including orthopnea and paroxysymal nocturnal dyspnea (PND) Physical exam bibasilar inspiratory crackles due to air expanding fluid-filled alveoli rusty-colored sputum due to rupture of pulmonary capillaries from elevated hydrostatic pressure wheezing due to peribronchiolar edema "cardiac asthma" Evaluation CXR congestion in upper lobes perihilar congestion "bat wing configuration" alveolar infiltrates Kerley's lines due to septal edema Biopsy hemosiderin-laden alveolar macrophages ("heart failure cells") macrophages phagocytose blood following rupture of capillaries Treatment Treat underlying condition nitrates and diuretics used for cardiogenic causes Respiratory support Non-invasive positive pressure ventilation supplemental oxygen