Edema
Edema | |
---|---|
Other names | Oedema, œdema, fluid retention, water retention, dropsy, hydropsy, swelling |
physical exam[3] | |
Treatment | Based on cause[2] |
Edema, also spelled oedema, and also known as fluid retention, dropsy, hydropsy and swelling, is the build-up of fluid in the body's tissue.[1] Most commonly, the legs or arms are affected.[1] Symptoms may include skin which feels tight, the area may feel heavy, and joint stiffness.[1] Other symptoms depend on the underlying cause.[2]
Causes may include
Treatment depends on the underlying cause.
Signs and symptoms
Specific area
An edema will occur in specific organs as part of inflammations,
- Peripheral edema (“dependent” edema of legs) is extracellular fluid accumulation in the lower extremities caused by the effects of gravity, and occurs when fluid pools in the lower parts of the body, including the feet, legs, or hands. This often occurs in immobile patients, such as paraplegics or quadriplegics, pregnant women, or in otherwise healthy people due to hypervolemia or maintaining a standing or seated posture for an extended period of time. It can occur due to diminished venous return of blood to the heart due to congestive heart failure or pulmonary hypertension. It can also occur in patients with increased hydrostatic venous pressure or decreased oncotic venous pressure, due to obstruction of lymphatic or venous vessels draining the lower extremity. Certain drugs (for example, amlodipine) can cause pedal edema.
- Cerebral edema is extracellular fluid accumulation in the brain.[1] It can occur in toxic or abnormal metabolic states and conditions such as systemic lupus or reduced oxygen at high altitudes. It causes drowsiness or loss of consciousness, leading to brain herniation and death.
- pleuralcavity.
- Edema may also be found in the cornea of the eye with glaucoma, severe conjunctivitis, keratitis, or after surgery. Affected people may perceive coloured haloes around bright lights.
- Edema surrounding the eyes is called periorbital edema(puffy eyes) . The periorbital tissues are most noticeably swollen immediately after waking, perhaps as a result of the gravitational redistribution of fluid in the horizontal position.
- Common appearances of western poison oak,[5] the latter of which are termed contact dermatitis.
- Another cutaneous form of edema is hyaluronin) deposited in the tissue matrix. Edema forms more easily in dependent areas in the elderly (sitting in chairs at home or on aeroplanes) and this is not well understood. Estrogens alter body weight in part through changes in tissue water content. There may be a variety of poorly understood situations in which transfer of water from tissue matrix to lymphatics is impaired because of changes in the hydrophilicity of the tissue or failure of the 'wicking' function of terminal lymphatic capillaries.
- Myoedema is localized mounding of muscle tissue due to percussive pressure, such as flicking the relaxed muscle with the forefinger and thumb. It produces a mound, visible, firm and non-tender at the point of tactile stimulus approximately 1-2 seconds after stimulus, subsiding back to normal after 5-10 seconds. It is a sign in hypothyroid myopathy, such as Hoffmann syndrome.[6]
- In radiotherapy, or infiltration of the lymphatics by infection (such as elephantiasis). It is most commonly due to a failure of the pumping action of muscles due to immobility, most strikingly in conditions such as multiple sclerosis, or paraplegia. It has been suggested that the edema that occurs in some people following use of aspirin-like cyclo-oxygenase inhibitors such as ibuprofen or indomethacin may be due to inhibition of lymph heart action.
Generalized
A rise in
Causes of edema which are generalized to the whole body can cause edema in multiple organs and peripherally. For example, severe heart failure can cause pulmonary edema, pleural effusions, ascites and peripheral edema. Such severe systemic edema is called anasarca. In rare cases, a parvovirus B19 infection may cause generalized edemas.[8]
Although a low plasma oncotic pressure is widely cited for the edema of nephrotic syndrome, most physicians note that the edema may occur before there is any significant protein in the urine (proteinuria) or fall in plasma protein level. Most forms of nephrotic syndrome are due to biochemical and structural changes in the basement membrane of capillaries in the kidney glomeruli, and these changes occur, if to a lesser degree, in the vessels of most other tissues of the body. Thus the resulting increase in permeability that leads to protein in the urine can explain the edema if all other vessels are more permeable as well.[9]
As well as the previously mentioned conditions, edemas often occur during the late stages of pregnancy in some women. This is more common with those of a history of pulmonary problems or poor circulation also being intensified if arthritis is already present in that particular woman. Women who already have arthritic problems most often have to seek medical help for pain caused from over-reactive swelling. Edemas that occur during pregnancy are usually found in the lower part of the leg, usually from the calf down.
Hydrops fetalis is a condition in a baby characterized by an accumulation of fluid in at least two body compartments.
Cause
Heart
The pumping force of the
Kidneys
Another cause of severe water retention is
Liver
Cirrhosis (scarring) of the liver is a common cause of edema in the legs and abdominal cavity.[12]
Veins
Phlebetic lymphedema (or phlebolymphedema) is seen in untreated chronic venous insufficiency and is the most common type of edema (approx. 90%).[13] It is a combination venous/lymphatic disorder that originates in defective "leaky" veins that allows the blood to back flow (venous reflux), slowing the return of the blood to the heart (venous stasis). The venous pressure in the legs changes dramatically while standing compared to lying down. How much pressure there is depends on the person's height, in the average adult person, it is 8 mm Hg while lying down and 100 mm Hg while standing.[14]
In venous insufficiency, venous stasis results in abnormally high venous pressure (venous hypertension) and greater permeability of blood capillaries (capillary hyperpermeability), to drain the blood through the lymphatic system. The lymphatic system slowly removes excess fluid and proteins from the veins in the lower legs towards the upper body; however, as it is not as efficient as an unimpaired circulatory system, swelling (edema) is visible, particularly in the ankles and lower leg. Unfortunately, the chronic increased fluid in the lymphatic system and capillary hyperpermeability causes an inflammatory response which leads to tissue fibrosis of both veins and lymphatic system, opening of arteriovenous shunts, all of which then worsens the condition in a vicious cycle.[13][14]
Others
Swollen
Lack of exercise is another common cause of water retention in the legs. Exercise helps the leg
Certain
Mechanism
Six factors can contribute to the formation of edema:[23]
- increased hydrostatic pressure;
- reduced colloidal or oncotic pressure within blood vessels;
- increased tissue colloidal or oncotic pressure;
- increased blood vessel wall permeability (such as inflammation);
- obstruction of fluid clearance in the lymphatic system;
- changes in the water-retaining properties of the tissues themselves. Raised hydrostatic pressure often reflects retention of water and sodium by the kidneys.[24]
Generation of interstitial fluid is regulated by the forces of the
Changes in the variables in Starling's equation can contribute to the formation of edemas either by an increase in hydrostatic pressure within the blood vessel, a decrease in the oncotic pressure within the blood vessel or an increase in vessel wall permeability. The latter has two effects. It allows water to flow more freely and it reduces the colloidal or oncotic pressure difference by allowing protein to leave the vessel more easily.[citation needed]
Another set of vessels known as the
Diagnosis
Grade | Definition |
---|---|
Absent | Absent |
+ | Mild: Both feet / ankles |
++ | Moderate: Both feet, plus lower legs, hands or lower arms |
+++ | Severe: Generalised bilateral pitting edema, including both feet, legs, arms and face |
Edema may be described as pitting edema, or non-pitting edema.[29] Pitting edema is when, after pressure is applied to a small area, the indentation persists after the release of the pressure. Peripheral pitting edema, as shown in the illustration, is the more common type, resulting from water retention. It can be caused by systemic diseases, pregnancy in some women, either directly or as a result of heart failure, or local conditions such as varicose veins, thrombophlebitis, insect bites, and dermatitis.[30]
Non-pitting edema is observed when the indentation does not persist. It is associated with such conditions as lymphedema, lipedema, and myxedema.
Edema caused by malnutrition defines kwashiorkor, an acute form of childhood protein-energy malnutrition characterized by edema, irritability, anorexia, ulcerating dermatoses, and an enlarged liver with fatty infiltrates.
Treatment
When possible, treatment involves resolving the underlying cause. Many cases of
Treatment may also involve positioning the affected body parts to improve drainage. For example, swelling in feet or ankles may be reduced by having the person lie down in bed or sit with the feet propped up on cushions. Intermittent pneumatic compression can be used to pressurize tissue in a limb, forcing fluids—both blood and lymph—to flow out of the compressed area.[31]
References
- ^ a b c d e f g h Causes and signs of edema. Institute for Quality and Efficiency in Health Care (IQWiG). 2016.
- ^ a b c d e f g h i "Edema - Cardiovascular Disorders". Merck Manuals Professional Edition. Retrieved 8 December 2019.
- ^ a b c "Edema: Causes, Symptoms, Diagnosis & Treatment". Family doctor. Retrieved 23 December 2019.
- ^ Liddell H. "οἴδ-ημα". A Greek-English Lexicon. Tufts. Retrieved 8 December 2019.
- ^ Hogan CM (2008). Strömberg N (ed.). "Western poison-oak: Toxicodendron diversilobum". GlobalTwitcher. Archived from the original on July 21, 2009.
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- ^ PMID 30310422.
- ^ "Edema - Symptoms and causes". Mayo Clinic. Retrieved 2022-07-19.
- ^ "Edema - Symptoms and causes". Mayo Clinic. Retrieved 2022-12-23.
- ^ a b Publishing L, Guiboles (2009-11-24). "The causes of edema in chronic venous insufficiency". Servier - Phlebolymphology. Retrieved 2023-09-01.
- ^ PMID 24527138.
- The Merck Manual. Retrieved 9 August 2017.
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- ISBN 978-1-58890-284-9.
- ^ "Estrogens (Conjugated/Equine)". The Merck Manual. Archived from the original on 2 December 2007. Retrieved 9 August 2017.
- ^ "Beta-Blockers for High Blood Pressure". WebMD. Retrieved 9 August 2017.
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- ^ Scallan J, Huxley VH, Korthuis RJ (2010). Pathophysiology of Edema Formation. Morgan & Claypool Life Sciences. Retrieved 11 July 2022.
- ISBN 0-7216-0187-1.
- ^ Boron WF, Boulpaep EL (2012). "2e". Medical Physiology: A Cellular and Molecular Approach. Philadelphia: Saunders/Elsevier.
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- ISBN 978-0-78177-324-9.
- ^ Nutrition in Emergencies > Measuring œdema Archived 2017-02-18 at the Wayback Machine. Erin Boyd, reviewed by Diane Holland, Nutrition in Emergencies Unit, UNICEF. Retrieved Nov 2012
- ^ Booth S. "Pitting Edema". WebMD. Retrieved 1 January 2023.
- ^ Causes and signs of edema. Institute for Quality and Efficiency in Health Care (IQWiG). 30 December 2016. Retrieved 26 July 2022.
- PMID 25748341.