Do you know about pedal edema?

Sometimes individuals develop swelling over feet, known as pedal edema.  It becomes worrisome and generates anxiety. It can be due to multiple causes. Timely detection and treatment of underlying cause cures it.

Normally, plasma volume inside the body is kept constant by various forces. Any disturbance in these forces can cause edema. It is clearly visible to the naked eye and one can make an indent while pressing it.

Edema may develop over one feet or both. One sided edema can be due to acute or chronic infection, formation of clots in the leg, blockade of lymphatics by infection or   cancer, trauma, and etcetera. The swelling can remain confined to the foot. If the cause persists, it can spread to the entire leg.  The reason for edema can be detected by physical examination and investigations like Doppler examination. Any root cause detected can be treated.

Edema involving both feet can occur due to   disorders of heart, liver, kidney, thyroid or protein malnutrition. These disorders alter the hemodynamic forces maintaining fluid and electrolyte balance in various ways, leading to accumulation of fluid in the feet. In heart failure, edema initially appears in both feet after walking and then later becomes persistent. As disease advances, it spreads to the legs and then face and whole body.  The face looks puffy and tummy looks distended.  In kidney failure and protein deficient states, swelling over feet appears in later stages.

Fluid can collect in the lungs and even between coverings of the heart in severe disease due to any of these conditions.  This manifests as breathlessness on exertion and even on rest in later stages. A person finds it difficult to sleep in a supine position, as breathlessness is aggravated in this position.

Middle aged women can develop pedal edema due to changes in hormone levels. This is a benign harmless condition, which resolves by itself sometime after menopause. However, any sinister medical condition should be excluded by suitable investigations.

Swelling over feet should not be taken lightly. Something seemingly trivial may progress to some irreversible damage.  Once edema spreads from the feet to whole body, the functioning of heart and or lungs can be compromised.   But if diagnosed   early, the   condition producing bilateral pedal edema can be treated very well. Protein deficiency can be assessed by other clinical signs and estimating blood levels of proteins. It is reversible, after the deficiency is corrected.

The condition causing pedal edema can be diagnosed clinically by a good history and physical examination. Relevant tests can help to confirm or exclude a condition. These include tests for heart, kidney, liver and the thyroid gland. 

Salt restriction in the diet is useful to manage pedal edema. However, total absence of salt can cause muscle cramps and weakness, hence, one should be vigilant about it.   Diuretic drugs, that is, drugs which promote mobilisation of extra fluid and salt from the body are used in all cases of edema. When these are taken for a prolonged time, the swelling becomes refractory sometimes, necessitating increase of dose. The risk of side effects like electrolyte imbalance, muscle cramps, ringing sensation in ears, photophobia, and etcetera, is also increased. Thus, a vicious cycle is established where one cannot do without the diuretic drug and after taking it suffers from side effects. Rest reduces the metabolism of the body. This   provides   rest to the affected part by reducing work load on it and also helps reducing breathlessness due to edema.

The specific treatment is treatment of the underlying cause. Therefore, it is advisable that if edema is noticed on the feet anytime, it should not be neglected.