Oedema

Also called Swollen ankles, Fluid retention, Swollen legs

Swelling from fluid in the tissues. Both legs usually means the heart, kidneys, liver or a drug; one leg means look for a clot.

What it is

Swelling caused by fluid collecting in the tissues, most often in the ankles, feet and lower legs.

The most useful diagnostic question is whether it is one leg or both.

**Both legs** usually means a systemic cause: heart failure, chronic kidney disease, cirrhosis, low protein from malnutrition, or simply immobility and gravity. Medicines are a very common and very fixable cause, particularly calcium channel blockers such as amlodipine, and also anti-inflammatories, steroids, gabapentin and pregabalin.

**One leg** means think about a deep vein thrombosis, cellulitis, or a local problem, and is the presentation that most often needs same-day assessment.

Long-standing oedema damages skin. It causes leg ulcers, fragile weeping skin, and lymphoedema when the lymphatic system becomes overwhelmed.

Treating oedema means treating its cause. Diuretics are appropriate for heart failure and inappropriate for swelling caused by immobility or by a calcium channel blocker, where they cause dehydration and acute kidney injury without helping. That is a common and harmful error.

Signs you might notice

Swelling of the ankles, feet and lower legs, often worse by the evening and better after a night lying flat.

Skin that pits when pressed and takes seconds to spring back.

Tight, shiny skin, and difficulty getting shoes on.

Weight gain over days, which is the most sensitive early measure in heart failure.

Same-day: swelling of one leg with pain, warmth or redness; swelling with breathlessness or chest pain; swelling that appears suddenly.

999: severe breathlessness, especially lying flat, or breathlessness with frothy or pink sputum.

Urgent: swelling with reduced urine output, or with weeping skin that is breaking down.

How it can affect day-to-day life

Daily weights are the single most useful measurement, particularly in heart failure. A rise of two to three kilograms over a few days is fluid, and it is the trigger for action long before anybody is breathless.

Elevation genuinely works, and it has to be above hip level to do anything. Feet on a footstool is not elevation.

Compression helps in venous oedema and is dangerous if the arteries are narrowed, so an arterial assessment comes first. See peripheral arterial disease.

Weeping legs are a nursing emergency of sorts: the skin breaks down quickly and becomes infected, and getting district nursing and appropriate dressings early prevents months of ulceration.

Salt intake matters more than fluid restriction in most cases, and is rarely discussed.

In care settings, prolonged sitting with legs down is a major and preventable cause; moving people and elevating legs matters as much as any medicine.

Supporting someone well

Establish whether it is one leg or both. That question directs everything.

Get one-sided swelling assessed the same day.

Weigh daily at the same time, and report a gain of two to three kilograms over a few days.

Elevate the legs above hip level for periods during the day, and keep moving; ankle pumps in a chair help.

Ask for a medication review, particularly amlodipine and similar drugs, which cause a great deal of unnecessary swelling.

Do not add a diuretic for drug-induced or immobility-related swelling; change the cause instead.

Get arterial circulation checked before using compression.

Protect the skin, moisturise, and get weeping legs seen by a nurse promptly.

Reduce salt.

Where to get help

A GP practice for new or worsening swelling, and for a medication review.

Same-day assessment for one-sided swelling, or swelling with breathlessness.

999 for severe breathlessness or chest pain.

British Heart Foundation on 0808 802 1234, and Legs Matter for leg and skin problems.