Chapter 033. Dyspnea and Pulmonary Edema (Part 6) Distinguishing Cardiogenic from Noncardiogenic Pulmonary Edema The history is essential for assessing the likelihood of underlying cardiac disease as well as for identification of one of the conditions associated with noncardiogenic pulmonary edema. The physical examination in cardiogenic pulmonary edema is notable for evidence of increased intracardiac pressures (S3 gallop, elevated jugular venous pulse, peripheral edema), and rales and/or wheezes on auscultation of the chest. In contrast, the physical examination in noncardiogenic pulmonary edema is dominated by the findings of the precipitating condition; pulmonary findings may be relatively normal in the early stages. The chest radiograph in cardiogenic pulmonary edema typically shows an enlarged cardiac silhouette, vascular redistribution, interstitial thickening, and perihilar alveolar infiltrates; pleural effusions are common. In noncardiogenic pulmonary edema, heart size is normal, alveolar infiltrates are distributed more uniformly throughout the lungs, and pleural effusions are uncommon. Finally, the hypoxemia of cardiogenic pulmonary edema is due largely to ventilation-perfusion mismatch and responds to the administration of supplemental oxygen. In contrast, hypoxemia in noncardiogenic pulmonary edema is due primarily to intrapulmonary shunting and typically persists despite high concentrations of inhaled O 2 . Further Readings Abidov A et al: Prognostic significance of dyspnea in patients r eferred for cardiac stress testing. N Engl J Med 353:1889, 2005 [PMID: 16267320] Dyspnea mechanisms, assessment, and management: A consensus statement. Am Rev Resp Crit Care Med 159:321, 1999 Gillette MA, Schwartzstein RM: Mechanisms of dyspnea, in S upportive Care in Respiratory Disease , SH Ahmedzai and MF Muer (eds). Oxford, U.K., Oxford University Press, 2005 Mahler DA et al. Descriptors of breathlessness in cardiorespiratory diseases. Am J Respir Crit Care Med 154:1357, 1996 [PMID: 8912748] ———, O'Donnell DE (eds): Dyspnea: Mechanisms, Measurement, and Management . New York, Marcel Dekker, 2005 Schwartzstein RM. The language of dyspnea, in Dyspnea: Mechanisms, Measurement, and Management , DA Mahler and DE O'Donnell (eds). New York, Marcel Dekker, 2005 ———, Feller-Kopman D. Shortness of breath, in Primary Care Cardiology , 2d ed, E Braunwald and L Goldman (eds). Philadelphia: WB Saunders, 2003 . Chapter 033. Dyspnea and Pulmonary Edema (Part 6) Distinguishing Cardiogenic from Noncardiogenic Pulmonary Edema The history is essential for assessing. pulmonary edema. The physical examination in cardiogenic pulmonary edema is notable for evidence of increased intracardiac pressures (S3 gallop, elevated jugular venous pulse, peripheral edema) ,. and rales and/ or wheezes on auscultation of the chest. In contrast, the physical examination in noncardiogenic pulmonary edema is dominated by the findings of the precipitating condition; pulmonary