Definition
Cardiogenic pulmonary edema (CPE) is defined as development of pulmonary edema as a consequence of increased capillary hydrostatic pressure secondary to elevated pulmonary venous pressure.
Pathophysiology CPE
(1) increased capillary hydrostatic pressure
(2) increased capillary permeability
(3) decreased plasma oncotic pressure
(4) lymphatic obstruction
Starling equation
Q = K(P.cap – P.is) - l(P.cap- P.is)
Q is net fluid filtration.
K is a constant called the filtration coefficient.
Pcap is capillary hydrostatic pressure
Pis is hydrostatic pressure in the interstitial fluid.
l is the reflection coefficient, which indicates the effectiveness of the capillary wall in preventing protein filtration.
Pcap is the colloid osmotic pressure of plasma
Pis is the colloid osmotic pressure in the interstitial fluid
When the pulmonary capillary hydrostatic pressure exceeds pulmonary interstitial pressure, transudation of fluid in the pulmonary interstitium and alveoli occurs.