The nurse should keep which concept in mind when providing care to a patient with cardiogenic pulmonary edema?

Question

A) Increased left ventricular pressure is reflected back to the pulmonary capillary bed.
B) This condition is caused by decreased oncotic pressure due to anemia.
C) Capillary endothelial injury makes the capillaries leaky.
D) Lymphatic blockage prevents drainage of interstitial fluid.

Answer 1

A) Increased left ventricular pressure is reflected back to the pulmonary capillary bed.

Explanation: A) There are four pathophysiologic mechanisms that cause the formation of pulmonary edema. The mechanism that causes cardiogenic pulmonary edema is left ventricular failure. The increased left ventricular pressure is reflected back into the pulmonary capillary bed. The increased pulmonary capillary pressure (wedge pressure > 20 mmHg) increases the hydrostatic drive for fluid to flow from the capillaries into the interstitial space.
B) Pulmonary edema may also be caused by a decrease of oncotic pressure due to anemia or a decrease in plasma proteins. The pulmonary hydrostatic pressure is normal, but the oncotic pressure is not adequate to resorb normal amounts of fluid from the interstitial space. However, this is not cardiogenic pulmonary edema.
C) Capillary endothelial injury makes capillaries "leaky" so more fluid leaks into the interstitial space can also lead to pulmonary edema. However, this is not cardiogenic pulmonary edema.
D) Blockage of lymphatic drainage prevents the removal of excess fluid from the interstitial space and can lead to pulmonary edema. Normally, excess fluid in the lung interstitial space is collected at the periphery of acini to drain through the lymphatic system. However, this is not cardiogenic pulmonary edema.