Interstitial pulmonary edema.
Florid pulmonary edema is frequently preceded by interstitial edema formation. Because of alterations in the balance of oncotic and hydrostatic pressures between the capillary and lung interstitium or changes in capillary permeability, edema fluid forms in the interstitial spaces of the lung. Once the capacitance of the pulmonary lymphatics is exceeded, interstitial and alveolar edemas become more prominent. Bronchoconstriction and increased vascular resistance lead to ventilation-perfusion imbalance, reduced lung compliance, and increasing symptoms. Early detection is possible by noting characteristic changes in gas exchange and chest radiograph. Awareness and early recognition of these changes, together with the predisposing clinical settings, can lead to the institution of appropriate therapy before patients become severely ill with frank alveolar pulmonary edema.
D006801:Humans; D011654:Pulmonary Edema / Q000175:diagnosis / Q000209:etiology / Q000628:therapy