Noncardiogenic Pulmonary Edema in Dogs. Noncardiogenic edema is caused by an increased permeability (or the ability to pass through, as by osmosis) of the blood vessels of the lungs. This increased permeability results in the leakage of fluid into the lung, causing edema, or swelling. If this becomes severe, the edema may be accompanied by an inflammatory response and an accumulation of inflammatory cells in the lung.