Albumin is the most abundant protein in the blood. Because albumin is used to make many new cells, blood levels of albumin drop very quickly during critical illness. Normally, albumin and other proteins are too large to move across the walls of blood vessels. Following major surgery, trauma or critical illness, blood vessels often become very "leaky". This allows additional albumin to escape into the tissues, making the blood albumin level even lower.

Water is attracted to protein. When albumin moves into the tissues, the tissues fill up with water. Water that accumulates in the tissues is called Edema. Low albumin, inflammation, obstruction of the lymph nodes or increased pressure in the blood vessels can produce edema. Edema can cause tremendous swelling and puffiness throughout the body. Edema that collects under the skin is called peripheral edema. Edema can also collect around the lung, causing breathing problems. Edema around the lung is called pulmonary edema.

Edema fluid tends to travel in a pattern that matches gravity. Individuals who are standing or walking will develop more edema around the ankles. Patients lying in bed will develop more edema in their tailbone region or toward the back lobes of the lungs. During critical illness, edema can often become so severe that the patient's whole body becomes swollen and distorted looking. Edema fluid may even begin to weep from the skin surface. This seepage of fluid has a yellowish appearance, similar to the water portion of the blood (called plasma).

Although the change in the patient's appearance can be upsetting, edema fluid does go away when the patient gets better. We feed patients early to try to provide enough dietary protein, however, until the patient begins to recover, blood albumin levels often stay low.

ABOVE: Edema in the legs




Last Reviewed: October 23, 2014



LHSCPatients, Families & Visitors

Last Updated October 23, 2014 | © 2007, LHSC, London Ontario Canada