Information on pitting and non-pitting edema.
Select a Topic
- Types of Edema
- What are the Symptoms of Edema?
- What Causes Edema?
- Edema in Children & Infants
- Diagnosing Edema
- Treatments for Edema
- Tips for the Prevention of Edema
What is Edema?
Edema is the noticeable swelling resulting from fluid accumulation in certain body tissues. It is most commonly found in the feet, ankles, and legs although it may also affect the face, hands and other parts of the body and body organs. Pregnant women and older adults are often affected by this condition, but it can happen to anyone.
The swelling also referred to as dependent edema, is brought about by the accumulation of excess fluid beneath the skin in the interstitial spaces or compartments within the body tissues that are outside of the blood vessels. Excess fluid accumulation in the lower regions of the body, such as the ankles, feet, and legs, is referred to as peripheral edema.
Types of Edema
Clinically there are two types of edema – pitting and non-pitting edema. Pitting edema is the term used to describe edema when pressure applied to the skin of the swollen area is released and an indentation is left behind (e.g. when the skin is pressed with a finger or when stockings or socks induce indentation). Non-pitting edema is the term used to describe edema when this pressure-induced indentation does not occur. Non-pitting edema usually occurs in the arms and legs.
Occasionally pitting edema and non-pitting edema can occur without an underlying disease and it is then known as idiopathic edema. This is most common in women who experience it in their legs and feet when they are pre-menstrual or pre-menopausal – it is then often known as cyclical edema.
What are the Symptoms of Edema?
Symptoms of edema may include:
- Persistent indentation of the skin (Pitting)
- Swollen feet, ankles and legs
- Painful skin sensations such as burning, soreness, tingling
- Water retention or interstitial fluid
- Abdominal bloating
- Night sweats
- Skin that is warm or hot to the touch
What Causes Edema?
There are many factors that can contribute to the causes of edema. Since it is often related to an underlying condition, it’s important to get a proper diagnosis to be sure of the cause.
Possible Causes of Edema
- Pregnancy can cause edema in the legs as the uterus puts pressure on the vena cava, a major blood vessel that returns blood to the heart from the legs, and progesterone relaxes the walls of the blood vessels. Fluid retention during pregnancy also can be caused by a more serious condition called pre-eclampsia.
- High blood pressure (Hypertension), liver, kidney and thyroid diseases can cause edema
- Being largely overweight or obese. Excess weight can put added pressure on the knee and ankle joints and the lower limbs.
- Standing or sitting for long periods of time particularly in hot weather can cause excess fluid to accumulate in feet, ankles and lower legs.
- Low protein levels in the blood caused by malnutrition, kidney and liver disease can also cause edema. The proteins help to hold water inside the blood vessels so fluid does not leak out into the tissues. If a blood protein, called albumin, gets too low, fluid leaks out the blood vessels and edema occurs, especially in the feet, ankles and lower legs.
- Flying (Air Travel)
- Low Blood Pressure
- Poor Circulation
- Eating food with high salt content.
- Spider & Insect Bites
- Congestive heart failure is a condition in which the heart can no longer pump efficiently, and causes fluid buildup in the lungs and other parts of the body. Swelling is often most visible in the feet and ankles.
- Severe chronic (long-term) lung diseases, including emphysema and chronic bronchitis, increase pressure in the blood vessels that lead from the heart to the lungs. This pressure backs up in the heart and the higher pressure causes swelling in the legs and feet.
- Tiny valves inside the veins of the legs can become weakened, causing a common problem called venous insufficiency. This makes it more difficult for the veins to pump blood back to the heart and leads to varicose veins and a buildup of fluid.
Edema in Children & Infants
Most incidences of edema in children and infants are related to serious health conditions, so changes in your child should be monitored to avoid complications.
Children with acute or chronic upper airway obstruction are at risk for negative-pressure pulmonary edema, associated with upper airway obstruction. This condition may also occur after head injury, seizure, or accidental chemical ingestion or inhalation.
While quite rare, Nephrotic Syndrome (NS), a disorder of the kidneys, can cause edema in children. As the main symptom of NS, edema is commonly seen around one or both of the eyes, also referred to as periorbital edema, but may be found in other parts of the body such as the legs. Children with NS typically experience weight gain as a result of fluid accumulation. A urine test can confirm the diagnosis.
Periorbital edema should be closely monitored, as it may be the result of a more serious condition, such as congestive heart failure and liver diseases. Other causes of periorbital edema in children and infants may include allergies or infections, such as conjunctivitis.
Children and infants with diabetes may also experience edema as a side effect of insulin treatment. However, children with diabetes should report this to their pediatrician, as it may be a symptom of cerebral edema (brain swelling), a rare but serious complication of diabetes.
The diagnosis of pitting and non-pitting edema is determined by the symptoms upon physical examination. The doctor will examine the skin over the swollen area to check whether it may be stretched or shiny. By pushing gently on the swollen area for approximately 15 seconds, a dimple or indentation may be caused. Additional tests such as a urine test, blood test, a chest X-ray and electrocardiogram (ECG) may also be performed to confirm the cause of the edema.
Edema itself is usually a symptom of an underlying condition and can be noticed as swelling or puffiness of your face, hands, feet, legs, or around your eyes. Amongst others, edema can indicate disease of the heart, liver, thyroid, lymphatic system or kidneys (causing salt retention).
If you experience shortness of breath, chest pain, redness or heat in a swollen edematous area, or a swelling of only one limb, consult a doctor immediately. Also, pregnant women who notice signs of edema should seek medical help. Because edema can be a symptom of a serious underlying disorder and can cause serious consequences itself, it is always important to seek medical advice.
Treatments for Edema
Depending on the causes of edema and whether it is temporary or permanent, treating edema usually focuses on treating the condition that is causing it. A low dose of a diuretic (water pill) may be prescribed to reduce the swelling and help you expel the excess fluid, but it is important to remember this just treats the symptom and is not necessarily addressing the cause.
If a blocked or damaged blood vessel is suspected as one of the causes of edema, surgery may be needed to improve the flow of blood. Blood thinners may also be prescribed to treat blood clots, which can cause edema. As the clot begins to break down, fluid drainage improves and thus swelling is reduced.
Treating edema should include protecting any swollen, edematous areas of the body from pressure, injury and extreme temperatures. The skin over swollen areas becomes more fragile over time. Cuts, scrapes, and burns in areas that have edema take much longer to heal and are open to infection.
Tips for the Prevention of Edema
- Follow a low salt diet
- Avoid drinking too many fluids
- If you are overweight or obese, try to lose weight and reduce the pressure on your lower limbs and joints
- Elevate your legs above the level of your heart to keep swelling down and improve blood flow
- If your ankles and feet are swollen during pregnancy, keep your legs elevated and lie on your side rather than your back
- When you do lie down, place a pillow under your legs
- Wear support or compression stockings to improve the flow of blood through the veins
- Avoid leg swelling on long trips by standing up and walking around often or get up every hour
- Exercise your feet and lower legs while sitting as this will help the veins move blood back toward the heart
- Avoid smoking and drinking alcohol
- Try massage therapy, which stimulates blood flow and improves circulation