Lymphatics and Obstetrics Flashcards
Function of the lymph system
- collection and transportation of fluids and other materials that are not reabsorbed by the venous system
- maintenance of fluid balance within the body
- immune system defense
- The lymphatic system is normally responsible for collecting 10-20% of the interstitial fluid, while the venous system collects the other 80-90%.
What is lymph?
- Fluid transported by the lymphatics
- originates as component of interstitial fluid and primarily consists of water, proteins, fatty acids, and cellular components.
What does the lymphatic system consist of?
- network of both superficial and deep lymph vessels that transport lymph throughout the body.
- lymph vessels are located anywhere that a blood supply exists, except for the brain and spinal cord.
- Initial lymph vessel: The first lymph vessel within the lymphatic system is the smallest vessel
- located near blood capillaries and are responsible for collecting fluid from the interstitium that is not picked up by the venous system.
- The lymphatic system also transports the majority of extracellular proteins since they are often too large to be transported by the venous system.
- Initial lymph vessels – lymph collectors –lymphatic trunks (from smallest to largest)
Draining of the R lymphatic duct and thoracic duct
R lymphatic duct: drains lymph from R arms and R side of head
Thoracic duct: drains lymph from remainder of the body
These vessels empty lymph directly into the venous system via the subclavian veins.
What controls the lymphatic system?
- Under the control or the autonomic nervous system
- Produces contractions of smooth muscle within the lymph vessel walls to help move the lymph fluid along.
- Skeletal muscle contraction can also help to compress the lymph vessels and move lymph.
- One-way valves help maintain the unidirectional flow of lymph throughout the entire lymphatic system.
Where are lymph nodes found?
- Lymph nodes are specialized structures contained throughout the lymphatic system,
- Found most commonly in the neck, axilla, chest, abdomen, and groin.
- The lymph nodes collect lymph from several adjacent areas and function primarily to filter waste products and foreign materials from the lymph (e.g., bactena, viruses) and provide immune system defense with the use of T and B lymphocytes.
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Other components of the lymph system
Other components of the lymphatic system include the thymus. bone marrow, spleen, tonsils, and ever patches in the send intestine. These structures are involved in the production d lymphocytes, which are important to the functioning of the
immune system
Lymphedema
- A chronic, incurable condition and is characterized by the accumulation of protein-rich fluid (i.e., lymph) in the body.
- The result is edema that typically presents in the extremities, but can occur anywhere in the body including the face, neck, abdomen, genitalia, and trunk.
- Fluid accumulation occurs secondary to damage to the lymph structures, which affects the normal flow of lymph.
*Lymphedema is categorized as either primary or secondary based on the etiology.
Primary lymphadema
- Due to an abnormal development of the lymphatic system. Though this may occur from birth, it may take several years before the patient becomes symptomatic.
- Abnormalities of the lymph system may include the absence of lymph vessels, a decrease in the number or size of lymph vessels, and/or an increased size of lymph vessels, which makes the valves incompetent.
- This type of lymphedema occurs more frequently in females and is usually seen in the lower extremities.
Secondary lymphadema
- Result of some other disease or injury that causes damage to the lymphatic system.
- This may include trauma, surgery, radiation, tumor growth, multiparity, chronic venous insufficiency or infection.
- In the US, breast cancer surgery and treatment is the most common cause for secondary lymphedema.
- When a patient has treatment for breast cancer, the risk for lymphedema increases significantly with axillary lymph node dissection and/or radiation therapy.
- More radical mastectomy procedures are also associated with an increased risk of developing lymphedema.
3 types of insufficiencies in the lymphatic system
- 3 types of insufficiencies in the lymphatic system that can lead to lymphedema.
- Dynamic insufficiency
- most common type of insufficiency and occurs when there is excess lymph circulating in the lymphatic system that exceeds the transport capacity of the system.
- Results in pitting edema.
- Examples of this type of insufficiency include chronic venous insufficiency, congestive heart failure, and pregnancy.
- Mechanical insufficiency
- transport capacity of the system is reduced due to damage to the lymph system.
- This type of insufficiency results in the more protein-rich lymphedema (i.e., non-pitting).
- Combined insufficiency
- occurs when there is both an increase in lymph fluid as well as a decrease in transport capacity.
Symptoms of lymphedema
- Primary sign of lymphedema is swelling in the extremities.
- Because the lymphatic system can no longer handle the volume of fluid that it normally would, excess fluid builds up in the interstitium and leads to enlargement of the affected limb.
- Patients will complain of achiness, fullness, and heaviness of the affected limb.
- As lymphedema progresses, the valves expand and become incompetent, which leads to further fluid accumulation.
- If the fluid stasis continues, the proteins begin to degrade which leads to the development of chronic inflammation and eventually fibrotic changes to the surrounding tissues.
- Fibrosis results in local hypoxia in the tissues, which causes further chronic inflammation and an increased risk for infection.
Imaging techniques to help diagnosis lymphadema
- typically diagnoses with thorough medical hx and physical exam
Direct lymphography:
- Injection of a contrast medium into a lymph vessel that allows for visualization of the entire lymph system through radiography.
- It is not commonly used due to complications caused by the contrast medium.
Indirect lymphography:
- Injection of a contrast medium (water-soluble) just under the skin to allow for visualization of the smaller superficial lymph vessels.
Lymphoscintigraphy:
- Injection of radioactive material that allows for visualization of the lymphatic system through nuclear medical imaging.
- The radioactive material is traced throughout the system to determine how effectively lymph is being transported.
- This method is preferred over direct lymphography since there are fewer complications.
- MRI and CT scan: These imaging techniques can be used to identify tumors that may be the cause of a patient’s lymphedema.
Circumferential measurement for lymphedema
(procedure, interpretation, and classification)
- most common method for measuring lymphedema
Procedure:
- Measurement made on a measuring board
- from a stand point of reference on the extremity that is replicable
- 7 circumference are recommended for UE and LE to deduce that fluid has been removed and not just redistributed.
Interpretation:
- compare to opposite limb when available
- difference of 2-3 cm b/n 4 comparative circumferences on BUE is evidence of lymphedema
Classifications:
- Mild: <3 cm diff b/n affected and unaffected
- Moderate: 3-5 sm diff b/n affected and unaffected
- Severe >5 cm diff b/n affected and unaffected
Staging of Lymphedema
0 = Latent/preclinical. No visible edema, though transport capacity of lymph system is affected
1 = REVERSIBLE lymphedema stage.
- PITTING EDEMA is present and increases with activity or heat.
- Diminishes with elevated or rest.
2 = Spontaneoulsly IRREVERSIBLE lymphedema.
- NON-PITTING EDEMA.
- NO CHANGE with elevated or rest.
- FIBROTIC CHANGE and increased infection.
- STEMMER SIGN (+).
3 = Lymphostatic ELEPHANTIASIS stage.
- Extensive non-pitting edema
- Significant fibrotic changes to skin
- presence of papillomas, deep skinfolds, and hyperkeratosis
- Infection is common at this stage
- Stemmer (+)
SPIT
Subclinical – Pitting edema – Irreversible – Trunk (elephantiasis)
Complete Decongestive Therapy and the 2 stages
- Treatment model that occurs in two different phases.
Phase I
- Intensive acute treatment phase
- Typically provided in an outpatient setting by a certified lymphedema therapist
- 4-6 weeks.
Phase II
- Self-management phase
- Consists of long-term management of symptoms utilizing various components of CDT.
- Patients may need to return to phase I treatment whenever a significant change in symptoms is noted.
- CDT consists of manual lymphatic drainage, compression therapy, exercise, and skin care.
Manual lymphatic drainage
- Techniques designed to move lymph around blockages in the lymphatic system and into desired areas where it can be drained.
- 1st: be directed at uninvolved areas to prepare those areas for new lymph flow,
- 2nd: then be directed towards the involved areas.
- It is important for therapists to know the location of lymph nodes since this will affect where they decide to perform manual strokes and in what direction.
- It is also important to know if lymph nodes are intact and functioning.
- Start with superficial massage to proximal segments and then move distally
Compression therapy for lymphedema
- Helps to maintain the reduction in edema that is achieved with MLD.
- Reduce limb size by improving the reabsorption ability of the capillaries and reducing the filtration of fluids into the interstitium.
- Can also help soften fibrotic tissues that may have formed.
- Phase I treatment = Short- stretch bandages are used due to low resting pressure and therefore do not constrict lymph flow like long-stretch bandages would.
- Phase lI treatment =
- Combination of compression garments (during the day) and compression bandages (during the night) are used.
- Compression garments should only be fitted once edema levels have plateaued.
- Bandages and garments should be graded compression.
Exercise for lymphedema
- Improve lymph flow by increasing lymph vessel contractions,
- Increasing fluid uptake in the initial lymph vessels,
- Improving the “muscle pump” to stimulate lymph flow,
- Increasing deep breathing which improves lymph flow in the thoracic duct.
- Must be monitored carefully when initiating an exercise program and their program should be gradually progressed.
- Low impact, aerobic activities are generally recommended at the onset since they are less likely to exacerbate the patient’s lymphedema.
Guideline:
- Starting with trunk exercises
- Followed by extremity exercises
(Working from the proximal joints to the distal joints.)
- The session should finish with additional trunk exercises and deep breathing to enhance lymphatic flow.
- Compression bandages garments should be used when exercising.
Skin care with lymphedema
- The skin is more prone to damage since the protein rich fluid of lymphedema impairs immune system function allowing for bacterial and fungal growth.
- Infections can lead to worsening of a patient’s lymphedema.
- Prevention is therefore of primary importance.
- The limb should be inspected and cleansed thorough each day
- Frequently apply moisturizing lotion.
- Any soaps or moisturizers should have low or neutral pH to avoid damage to the skin.
Contraindications to complete decongestive therapy
- Acute infection
- Cardiac edema
- Diabetes
- Hypertension
- Malignancy
- Renal insufficiency
- Deep vein thrombosis
Filariasis:
A disease caused by a parasitic infection that is most often seen in tropical climates.
It is one of the most common causes of secondary lymphedema worldwide.
Hyperkeratosis:
Thickening of the outermost layer of the skin, which is typically observed with stage 3 lymphedema.
Lymphadenitis:
Infection and inflammation of a lymph node, which may be acute or chronic.
Lymphadenomegaly:
Enlargement of lymph nodes, which commonly occurs secondary to cancer, infections, and allergic reactions.
Lymphadenopathy:
Any disease that affects the size, number or consistency of the lymph nodes.
