Patient is having anaphylactic shock due to allergy to peanuts. Given chest x-ray shows diffuse infiltrates in bilateral lung fields in a bat wing's pattern with normal size of hea ruling out any cardiac pathology. Noncardiogenic pulmonary edema is caused by changes in capillary permeability as a result of a direct or an indirect pathologic insult, while cardiogenic pulmonary edema occurs due to increased capillary hydrostatic pressure secondary to elevated pulmonary venous pressure. Major causes of noncardiogenic pulmonary edema are drowning, fluid overload, aspiration, inhalation injury, neurogenic pulmonary edema, acute kidney disease, allergic reaction, and adult respiratory distress syndrome. Noncardiogenic pulmonary edema shows the classic "batwing" pattern of pulmonary opacities radiating centrifugally from the hila with air bronchogram. Cardiomegaly, pleural effusion, and mediastinal widening are usually not seen. Cardiogenic edema is caused by factors leading to elevated left atrial pressures, such as atrial outflow obstruction (mitral stenosis, atrial myxoma), left ventricular systolic dysfunction (congestive hea failure), left ventricular diastolic dysfunction, left ventricular volume overload, left ventricular outflow obstruction, dysrhythmias, cardiomyopathies, and myocardial infarction. Cardiogenic pulmonary edema shows mediastinal widening in the form of increased vascular pedicle width (>53 mm), pleural effusion, cardiomegaly, peribronchial cuffing, upper lobe pulmonary venous diversion in the form of prominence of bronchovascular markings, Kerley B lines, opacities involving both the central as well as the peripheral lungs, and reduced lung volume.