Lymphedema Assessment Methods – Some Considerations

Lymphedema Assessment MethodsLymphedema is a progressive chronic condition that affects a significant number of people and can have harmful effects on the patient’s physical and psychosocial health. Often defined as swelling of one or more limbs that may also include a portion of the corresponding trunk, lymphedema can also affect the breast, head, neck or genitalia. While primary lymphedema is mainly associated with other anomalies and genetic disorders such as Turner syndrome, Xanthomatosis, Klinefelter syndrome, congenital absence of nails, Trisomy 21 and Distichiasis lymphedema syndrome, the secondary or acquired condition results from damage to the lymphatic vessels and/or lymph nodes, or from functional deficiency. If ignored, the condition may worsen and become difficult to manage.

The diagnosis of lymphedema can also be confirmed through other imaging modalities, including CT or MRI. Careful attention should be given to patient risk factors and specific findings on physical examination. Risk factors for lymphedema includeseroma formation, obesity, hypertension, insertion of pacemaker, orthopedic surgery, poor nutritional status, chronic skin disorders and inflammation, air travel and more.

In patients with chronic condition, a large amount of subcutaneous adipose tissue may form. For patients who are unresponsive to conservative therapy, several surgical options with varied proven efficacies have been used in appropriate candidates.

Lymphedema Assessment

An accurate assessment is critical for the appropriate treatment of lymphedema. Medical assessment is used to diagnose the condition and exclude other causes of swelling. In most cases, diagnosis will be on the basis of medical history and physical examination. Lymphedema assessment should be performed at the time of diagnosis and repeated periodically throughout the treatment. These assessment findings should be documented systematically using wound care software programs. Digital photography is also recommended as an appropriate means to subjectively record and monitor facial and genital lymphedema.

Assessment of the patient should be structured and ongoing, and patient records should include further details such as:

  • extent, location and duration of the edema
  • presence of lymphadenopathy (swollen lymph nodes)
  • involvement/quality of skin and underlying tissue
  • degree of shape distortion of the affected area
  • circumference and volume of the affected limb
  • presence of pitting (indicates excess interstitial fluid)

Methods to Measure Limb Volume

Limb volume measurement determines the severity of the condition, the appropriate management and the effectiveness of treatment.

  • Water displacement method - The ‘gold standard’ for calculating limb volume, this is the only reliable method available for the measurement of oedematous hands and feet. The method uses the principle that an object will displace its own volume of water.
  • Circumferential measurement – This most widely used method is easily accessible and its reliability can be improved if a standard protocol is followed. These measurements of limbs entered into a computer program determine both individual and excess limb volume.
  • Perometry - This assessment method uses infrared light beams to measure the outline of the limb, which helps to calculate the limb volume quickly and accurately.
  • Bioimpedance - The method measures tissue resistance to an electric current to determine extracellular fluid volume. However, this technique is currently of limited use in bilateral swelling.
  • Limitations of excess limb volume - Measurement of excess limb volume can be used to track sequential changes in limb circumference to indicate treatment progress. In patients with severe thickening of the outer skin layer (hyperkeratosis) or hardening of the skin with deep skin folds (elephantiasis), a proportion of the excess volume will be due to factors other than fluid accumulation.

Effective pain assessment includes documenting the cause, nature, frequency, timing, site, severity and impact of the pain. Nutritional assessment involves determining obesity and evaluating the patient’s diet. Using an advanced wound EMR, these assessment details can be documented much faster and more accurately.