Knowledge Base

Bioelectrical Impedance Spectroscopy & Lymphoedema

With bioelectrical impedance spectroscopy (BIS), medical patients and healthcare professionals can develop a greater understanding of the fluid changes in the body that may be associated with the condition lymphoedema.

BIS can be used as an effective early indicator to identify lymphoedema, preventing the progression of the condition, which can worsen if not diagnosed and treated.

This quick and non-invasive test indicates and monitors fluid changes, enabling lymphoedema patients to manage their condition alongside medical professionals.

What is BIS (Bioelectrical Impedance Spectroscopy)?

Bioelectrical impedance spectroscopy works by sending a low-level electrical current through the body and measuring the impedance (resistance) to the flow of this current - spectroscopy does this across 50 frequencies. BIS calculates body composition and hydrational values using Cole-Cole analysis.

After analysis, a summary of the values are displayed. These include; fat, water and lean tissue (fat free tissue). Allowing for a full the estimation of body composition and a detailed look at the patients health.

With equipment such as Bodystat’s Multiscan 5000, this procedure can be undertaken at the bed-side if required for complete ease and comfort to the person being measured.

What is BIS (Bioelectrical Impedance Spectroscopy)?

A picture is formed since muscle, fat, lean tissue and water will all have different resistance levels to the current.

Illustration showing difference between a healthy arm and one affected by lymphoedema.

Arm affected by lymphoedema (left).

Illustration showing difference between a healthy leg and one affected by lymphoedema.

Leg affected by lymphoedema (right).

What is Lymphoedema?

Lymphoedema is a condition characterised by swelling in the body’s tissues; this is caused by excess levels of lymph, a fluid responsible for transporting nutrients around the body. Lymphoedema is a long-term condition and typically presents as swelling in the arms or legs, although it can affect any part of the body.

Alongside swelling, lymphoedema symptoms may include:

Aching in the body parts affected
Reduced mobility
Skin infections
Fluid leaking through the skin
Other changes to the skin, such as thickening

What Causes Lymphoedema?

The lymphatic system is a network of vessels and glands in the body which helps to fight infection and drains excess fluid from tissues.

Lymph fluid is naturally occurring within the body and usually drains back into the bloodstream through lymph vessels. If these vessels become blocked or damaged, lymph fluid can build up and the resulting swelling is called Lymphoedema. There are primary and secondary causations of lymphoedema.

Primary lymphoedema is genetic, and can develop at any age, though it commonly begins anytime from infancy to early adulthood.
Secondary lymphoedema is the more common type. It can be caused by cancer treatment, an infection, injury, inflammation of the limb or lack of limb movement.

Cancer is a prominent cause of secondary lymphoedema. This can be a cancer involving the lymph system, surgery, or a treatment to the lymph nodes, such as radiotherapy and chemotherapy. Breast cancer, vulval cancer and penile cancer are some examples of cancer types that affect the lymph system.

What Is Extracellular Fluid and How Does It Relate to Lymphoedema?

Extracellular fluid refers to fluid that is not contained in cells; it can be found in blood, lymph, muscular and other body tissues. This fluid is crucial to providing a constant environment for healthy cell function.

The swelling associated with lymphoedema is caused by an increase in extracellular water and intracellular water, due to the failure or blockage of the lymphatic system when removing excess fluid. An increase in extracellular fluid is characteristic of early lymphoedema.

How Does BIS Detect Lymphoedema?

BIS can determine total body fluid, distinguishing both extracellular water (ECW) and intracellular water (ICW) separately.

When detecting lymphoedema, there is a proportional correlation between the increase in extracellular fluid and the decrease in impedance. This can be used to identify subclinical lymphoedema; the ability to do this is a current deficiency in other methods such as water displacement or measuring limb circumference.

The accuracy and reproducibility capability of BIS enables detection of changes to fluid volume which may be used in the identification of lymphoedema in subclinical stages, as well as management of the condition over time. Early detection of lymphoedema can reduce the severity of the condition, potentially preventing it from progressing to the chronic stage; the role of BIS and level of information it can provide regarding changes in fluid composition can be key to this.

How Does BIS Help to Provide Better Health Care Analysis for Those Living with Lymphoedema?

The use of BIS in subclinical detection is evident. However, lymphoedema cannot be cured, so managing the condition over time is also critical for a patient’s wellbeing.

Bioelectrical impedance spectroscopy can aid those living with chronic lymphoedema, by tracking changes and monitoring the condition to determine effective treatment of symptoms. BIS is suitable for this due to its convenience – it is carried out with portable equipment and can be undertaken at home or in healthcare facilities. It is also painless, eliminating trauma experienced by a patient who has undergone repeated uncomfortable procedures.

With the ability to identify subclinical lymphoedema, and its potential to help manage long-term symptoms, bioelectrical impedance spectroscopy can vastly improve our understanding and therefore management of lymphoedema. This can have a great impact in preventing chronic lymphoedema, as well as a patient’s well being living with the condition.