Which of the following changes describe the pathophysiology involved in the production of pulmonary edema in patients with CHF? (AIPG 2011)
|A||Decreased plasma oncotic pressure|
|B||Widespread endothelial damage|
|C||Increased hydrostatic pressure|
|D||Increased vascular permeability|
a. Edema is the accumulation of excess fluid in the interstitial tissue or body cavities.
b. It may be caused by inflammation (inflammatory edema) or it may be due to abnormalities involving the Starling forces acting at the capillary level (noninflammatory edema or hemodynamic edema).
c. Inflammatory edema is caused by increased capillary permeability which is the result of vasoactive mediators of acute inflammation.
Exudate is inflammatory edema fluid resulting from increased capillary permeability.
· It is characterized by a high protein content, much cellular debris, and a specific gravity greater than 1.020.
· Pus is an inflammatory exudate containing numerous leukocytes and cellular Debris in contrast; transudates result either from increased intravascular hydrostatic pressure or from decreased osmotic pressure.
· They are characterized by a low protein content and a specific gravity of <1.012.
· Non- inflammatory edema is the result of abnormalities of the hemodynamic Starling) forces acting at the level of the capillaries.
· Increased hydrostatic pressure may be caused by arteriolar dilation, hypervolemia, or increased venous pressure.
· Hypervolemia may be caused by sodium retention seen in renal disease, and increased venous hydrostatic pressure can be seen venous thrombosis, congestive heart failure, or cirrhosis.
· Decreased plasma oncotic pressure is caused by decreased plasma protein, the majority of which is albumin.
· Decreased albumin levels may be caused by loss of albumin in the urine, which occurs in the nephrotic syndrome, or by reduced synthesis, which occurs in chronic liver disease.