the accumulation of excess fluid in a fluid compartment. Formerly called dropsy
. adj., adj
edem´atous. This accumulation can occur in the cells (cellular edema
), in the intercellular spaces within tissues (interstitial edema
), or in potential spaces within the body. Edema may also be classified by location, such as pulmonary edema or brain edema; types found in certain locations have specific names, such as ascites
(peritoneal cavity), hydrothorax
(pleural cavity), or hydropericardium
(pericardial sac). Massive generalized edema is called anasarca
. Classification by location does not indicate whether the edema is cellular or interstitial or occupies a potential space (for example, brain edema may be either cellular or interstitial). Edema can be caused by a variety of factors, including conditions that affect osmotic pressure, such as hypotonic fluid overload, which allows the movement of water into the intracellular space, or hypoproteinemia, which decreases the concentration of plasma proteins and permits the passage of fluid out of the blood vessels into the tissue spaces. Other factors include poor lymphatic drainage; conditions that cause increased capillary pressure, such as excessive retention of salt and water and heart failure; and conditions that increase capillary permeability, such as inflammation.
Edema formation. With trauma, increased capillary permeability and dilation cause leaking into tissue space. Initially clear, exudate in the tissue space becomes more viscous with an increase in plasma protein. From Copstead and Banasik, 2000.
alveolar edema pulmonary edema in the alveoli, usually with hypoxemia and dyspnea.
a manifestation of congestive heart failure
, due to increased venous and capillary pressures and often associated with renal sodium retention.
cellular edema edema caused by the entry of water into the cells, causing them to swell. This may occur because of decreased osmolality of the fluid surrounding the cells, as in hypotonic fluid overload, or increased osmolality of the intracellular fluid, as in conditions that decrease the activity of the sodium pump of the cell membrane, allowing the concentration of sodium ions within the cell to increase.
cerebral edema swelling of the brain caused by the accumulation of fluid in the brain substance. It may result from head injury, stroke, infection, hypoxia, brain tumors, obstructive hydrocephalus, and lead encephalopathy; it may also be caused by disturbances in fluid and electrolyte balance that accompany hemodialysis and diabetic ketoacidosis. The most common type is vasogenic edema, which may result from increased capillary pressure or from increased capillary permeability caused by trauma to the capillary walls. Cellular edema may occur in ischemia or hypoxia of the brain. Because the brain is enclosed in the solid vault of the skull, edema compresses the blood vessels, decreasing the blood flow and causing ischemia and hypoxia, which in turn result in further edema. Unless measures are taken to reverse the edema, destruction of brain tissue and death will result.
dependent edema edema of the lowermost parts of the body relative to the heart; it is affected by gravity and position, so that the lower limbs are affected if the individual is standing, but the buttocks are affected if the individual is supine.
generalized edema edema that is caused by poor venous return; it is not localized by the effects of gravity, in contrast to dependent edema.
1. edema caused by the accumulation of fluid in the extracellular spaces of a tissue.
2. pulmonary edema in the interstitial tissues; there is dyspnea but no hypoxemia.
edema in which pressure does not leave a depression in the tissues, such as in cellular edema
. See also pitting edema
pedal edema swelling of the feet and ankles.
peripheral edema edema affecting the extremities; seen in heart disease, Crohn's disease, and amyloidosis.
edema in which external pressure leaves a persistent depression in the tissues (see pitting
); it occurs because the pressure pushes the excess fluid out of the intercellular spaces in the tissue. See also nonpitting edema
diffuse extravascular accumulation of fluid in the tissues and air spaces of the lung
due to changes in hydrostatic forces in the capillaries or to increased capillary permeability. It is most often symptomatic of left ventricular heart failure
, but can also be a complication of mitral stenosis
, aortic stenosis
, altitude sickness
, acute hypertension
, volume overload during intravenous therapy, or reduced serum oncotic pressure, as in patients who have nephrosis
, or hypoalbuminemia
During the initial stage of pulmonary edema, patients may complain of restlessness and anxiety and the feeling that they are getting a common cold
. Other signs include a persistent cough, slight dyspnea
, and intolerance to exercise. On auscultation
can be heard over the dependent portion of the lung. As fluid continues to fill the pulmonary interstitial spaces the dyspnea
becomes more acute, respirations increase in rate, and there is audible wheezing. The cough becomes productive of frothy sputum tinged with blood, giving it a pinkish hue. Eventually, if the condition persists, the patient becomes less responsive to stimuli as levels of consciousness decrease. Ventricular arrhythmias develop and breath sounds
diminish. In some patients these phases are telescoped as the pulmonary edema develops rapidly and the final stages of respiratory insufficiency are evident in a very short period of time.
Treatment is aimed at enhancing gas exchange, reducing fluid overload, and strengthening and slowing the heart beat. To accomplish these goals the patient is often given oxygen by mask or through mechanically assisted ventilation. Drug therapy includes diuretics
to remove excess alveolar fluid and morphine
to relieve anxiety and reduce the effort of breathing. Administration of other medications depends on the cause of the edema, as well as what other problems the patient may be having.
that characterized by increased permeability of capillary endothelial cells; the most common form of cerebral edema
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.
Patient discussion about pedal edema
Q. My son's face and feet are very swollen when he wakes up. What is it? Can it infect my other boy? My 12 years old son's face and feet are very swollen when he wakes up. I saw it for the first time last week. He feels well and didn't notice anything by himself. Is it normal? I too have a swollen face when I wake up after sleeping with my face on the pillow but my legs are never swollen.
Another issue is that this boy sleeps in the same room with his 9 year old brother. Can he infect his brother? Do I need to separate them?
A. Swelling issues can be normal but might be pathologic. the major pathological issues that can cause it are autoimmune and thus not infections.
You should go and seek professional help, but unless the situation is getting worse or your son start develops another symptoms I advise you not to rush to the GP and definitely not to separate the kids.
Q. My left foot is swollen and painful. Can it be flesh eating bacteria? I am a 24 years old lady and my left foot is swollen and painful. To be more specific it is not just swollen it's red, painful and hot.
I just saw a TV show few days ago about "flesh eating bacteria". I know it sounds like I have hypochondria but I am very afraid.
A. To get a serious skin infection you need a port of entry for it. Think if you had any cosmetic therapy for your legs lately. If you can find a port of entry you can read here about cellulites - the name for swollen red and painful area of the skin. More discussions about pedal edema
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