A decrease in which of the following is the most likely cause of peripheral edema in a patient with long-term alcoholism and liver disease?
- Osmotic pressure of a solution is an indicator of the force of water movement resulting from its solute concentration. The higher the solute concentration of a solution, the greater its osmotic pressure. The plasma colloid osmotic pressure is often low in alcoholics with chronic liver disease (cirrhosis). The diseased liver cannot produce adequate amounts of albumin, which leads to a decrease in the concentration of albumin in the plasma (i.e., hypoalbuminemia).
- Because approximately 75% of the plasma colloid osmotic pressure can be attributed to the presence of albumin in the plasma, the decrease in plasma albumin concentration that occurs in the latter stages of cirrhosis often leads to peripheral edema. Cirrhosis also causes excess fluid to accumulate in the peritoneal cavity as ascites.
- In the case of ascites, the edema results not only from hypoalbuminemia, but also from portal vein obstruction (which increases capillary hydrostatic pressure) and the obstruction of lymphatic drainage of the liver. In fact, ascites is observed more often than peripheral edema in liver disease.
Capillary hydrostatic pressure
Interstitial colloid osmotic pressure
Interstitial hydrostatic pressure
Plasma colloid osmotic pressure