Which of the following is a known cause of vascular permeability (noncardiogenic) pulmonary edema?

• A. Amniotic fluid embolism
• B. Hypertension
• C. Heart failure
• D. Valvular disease

Answer: (A)

Noncardiogenic pulmonary edema stems from a disruption of the alveolar-capillary membrane, leading to leakage of fluid into the lungs due to increased capillary permeability rather than high pressure from the heart. Amniotic fluid embolism is a classic cause in obstetrics because it triggers a systemic inflammatory response that injures the pulmonary capillary endothelium, creating that capillary leak and rapid edema formation.

In contrast, hypertension, heart failure, and valvular disease cause edema mainly through elevated hydrostatic pressure from a failing or stressed heart, leading to cardiogenic edema. Thus, amniotic fluid embolism is the known noncardiogenic, permeability-type pulmonary edema among the options.