Is All Edema Lymphedema?
Updated: Feb 6
Summary and additional comments by Margaret Latham, DPT, CLT-LANA, ALM
The following is a more technical article primarily for clinicians and physicians. Dr. Margaret adds her thoughts in several sections and at the end about how these concepts affect aftercare treatment and healing for plastic surgery clients.
This information was provided by Heather Hettrick, PT, PhD, CWS, AWCC, CLT-LANA, CLWT, CORE, Professor for the Physical therapy program at Nova Southeastern University at a webinar sponsored by Lympha Press on February 17, 2022.
Is all Edema Lymphedema?
The short answer is YES! This is because we now know that the lymphatic system is responsible for returning nearly all excess fluid that accumulates in tissues to the venous system, whether temporary or not.
What is Edema?
It is swelling in the tissues related to fluid buildup. This fluid is lymph, which is what makes all edema lymphatic fluid.
Lymphatic load is everything absorbed by the lymphatic capillaries and transported by the lymphatic system which includes (1)
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Stagnant lymph can be toxic to the skin and cause lymphorrhea (leakage of lymph onto the skin) and ultimately lead to denudement or a chemical-like burn of the skin.
Edema Can be Anywhere!
Peripheral edema – localized to the feet, ankles, and lower leg
Pulmonary edema – lungs
Cerebral edema – brain
Ascites – edema in the abdominal spaces
Anasarca – full body edema
Third spacing – an outdated term where fluid moves from the vascular system to spaces between cells or body cavities that normally contain little to no fluid
Puffy Head Bird Leg Syndrome – 2-liter fluid shift from lower body to trunk/head due to loss of gravity (astronauts)
Causes of Edema
There are numerous (30+) causes of edema, however all are associated with the lymphatic system as it is all lymph fluid.
Severe inflammation
Burn injury
Trauma
Surgery
Immobility
Obesity/fat disorders
Poor nutrition
Allergic reaction
Medications
Congenital vascular malformations
Infections (viral, bacterial, parasitic)
Various disease states (CHF, CVI)
End-stage disorders (e.g., end stage renal disease)
Regardless of the cause, this edema is all still lymphatic fluid that increases our lymphatic load.
Lymphatic System and Circulation
The lymphatic system is a nodal-centric immune-vascular system. The lymphatics are the mortar that manages the interstitial fluid environment and mediates immunity and inflammation. (2)
The lymphatic system is the body’s drainage system. Fluid is taken from the tissues through the lymphatic vessels and lymph nodes.
lymphatic capillaries -> pre-collectors ->
collectors -> lymph nodes
The lymph nodes process molecules and debris in the fluid and the fluid continues through the lymphatic vessels until it returns to the venous system at the attachment of the lymphatic system to vein (venous angle) near the neck.
Classic Functions of the
Lymphatic System
Maintain interstitial fluid / protein balance.
The lymphatic system acts as a safety valve for fluid overload and helps keep edema from forming.
Fat absorption from the intestinal tract.
Immune response to infectious agents.
The homeostasis of the extracellular environment is maintained by the lymphatic system, and it cleanses the interstitial fluid and provides a blockade to the spread of infection or malignant cells in the lymph nodes. Langerhans cells (LCs), maintained in the skin, also serve to prevent unwanted organisms from entering our systems. These cells reside in the epidermis as a dense network of immune system sentinels. These cells determine the appropriate adaptive immune response (inflammation or tolerance) by interpreting the microenvironmental context in which they encounter foreign substances. In a normal physiological, “non-dangerous” situation, LCs coordinate a continuous state of immune tolerance, preventing unnecessary and harmful immune activation. Conversely, when they sense a danger signal, for example during infection or when the physical integrity of skin has been compromised as a result of a trauma, they instruct T lymphocytes of the adaptive immune system to mount efficient effector responses. (3)
Newly Appreciated Functions of the Lymphatic System
Reverse cholesterol transport.
Indirect regulation of brain function via cerebral lymphatics and “glymphatics.”
Organ growth and repair (i.e., cardiomyocytes, hair follicles)
Complications associated with the lymphatic system span a wide spectrum, including congenital disorders, cancer and side-effects of cancer treatments, cardiovascular disease, diabetes, and parasitic infections. While some lymphatic disorders are genetically related, lymphatic complications most often arise as a secondary complication following cancer, cardiovascular disease, and immunological diseases.
Lymphatic Vessel Engineering
Specific pathologies and areas that could benefit from improved lymphatic function or engineered lymphatic tissue are summarized in the graphic. Multiple areas of medicine and disease pathologies could benefit from advances in lymphatic tissue engineering. These include rescuing cardiac tissue after MI, clearing macromolecules from the brain to slow or hinder the onset of Alzheimer's disease, further understanding the pathways of cancer metastasis in order to effectively target cancer progression, designing improved organoids which would more accurately model native tissue, simulating lymphedema as an experimental model that could be used to design treatments for lymphedema beyond mechanical pumping, screening potential therapeutic agents to understand how they impact and interact with the lymphatic system, engineering superior skin grafts that incorporate the dermis and associated functionality, and promoting wound healing. (4)
Fluid Imbalance: Dynamic Insufficiency
Edema in the tissues is a symptom of another process such as injury or surgery. Our system becomes temporarily overwhelmed with fluid, but there is no damage to the lymphatic system.
Fluid Imbalance: Mechanical Insufficiency
We develop lymphedema as a disease process. The lymphatic system has some kind of permanent damage that prevents our system from being able to manage fluid accumulation effectively.
Lymphedema as a Disease
Most pathologies associated with the lymphatic system result in the clinical manifestation of edema/lymphedema. It is a chronic, uncurbable condition that is characterized by the abnormal collection of protein-rich fluid as a result of anatomical alterations to the lymphatic system (e.g., lymph node removal). It may lead to impairments in function, integument (skin) disorders, discomfort, and phycological issues.
Lymphedema can be primary (born with an issue, aka congenital) or secondary (acquired). It typically involves the arms or legs but can include the trunk, genitals, and other body locations. It can be on one side or both sides, but if it is on both sides, it is always asymmetrical.
Edema Versus Lymphedema
All edema is lymphatic fluid (must be removed by the lymphatic system).
Edema is the abnormal excess accumulation of serous fluid in the connective tissue. The lymphatic system is temporarily overwhelmed (lymphatic insufficiency), but not permanently damaged. This is low protein edema which has a watery consistency.
Lymphedema is the accumulation of protein rich fluid in an extremity or body part as a result of damage or loss (lymphatic impairment) to part of the lymphatic vessel/node system. Protein rich edema is progressive and permanent, and the fluid is viscous like honey in a Ziploc bag.
Think about lymphatic transport this way:
The lymphatics being temporarily overwhelmed is like going from a pick-up size transport capacity to a Fiat size transport capacity. This is most edema with more than 30 possible causes. It is transient lymphedema caused by processes such as injury, surgery, and congestive heart failure.
If the lymphatics are permanently impaired or damaged, this is the disease of lymphedema. Your Fiat is damaged beyond repair.
Food for Thought from Dr. Margaret
Where does post-op plastic surgery fit in? Off the cuff, as a plastic surgery recipient as well as a certified lymphedema therapist (CLT), I would say that most plastic surgery would result in a combination of normal, temporary post-op edema and a temporary, more prolonged edema caused by lymphatic system damage. We expect any lymphatic system damage to be healed within about 12 weeks, maybe less or maybe more depending on many factors.
Here is my new analogy about lymphatic transport after plastic surgeries:
Because you had surgery you downsized from a truck to a Fiat, but your Fiat gets wrecked as soon as you drive it off the lot. Fortunately, your new Fiat can be repaired by the local body shop with a little help from your CLT. (Pun intended :-) After your Fiat is repaired, you upsize it back to a pickup truck in a few months.
There is a significant component of lymphatic vessel damage with most body procedures (and some facial). The surgical effect of liposuction on the lymphatics is unique. Liposuction disrupts or destroys most lymphatic capillaries within the targeted adipose tissue. Fortunately, lymphatic damage from liposuction is not usually permanent. Lymphatic capillaries regenerate within a few weeks to several months after being damaged by a liposuction cannula. Damage may also occur due to severed vessels by incisions. We expect the lymphatic vessels to be able to be repaired by the body during healing, but this would likely take longer than the usual length of time for just post-op edema to resolve. Lymphatic vessels can regenerate and will normally regrow through scars less than about 3mm in width.
The result would be the likelihood of more prolonged swelling and its possible complications while the lymphatic system heals its “mechanical insufficiency” component as well as catches up from its post-op "dynamic insufficiency" component. In cases of lymphatic system damage from plastic surgery procedures, there is a combination of transient lymphedema caused by both a dynamic insufficiency as well as a (hopefully) temporary mechanical insufficiency of the lymphatic system. It is definitely food for thought in this context.
How does this information affect the answer to the question: "Do I need manual lymph drainage (“lymphatic massage”) after a tummy tuck?" During a typical tummy tuck, lower abdominal skin and tissue (below the belly button) is removed and upper abdominal skin and tissue (above the belly button) is pulled down to be the new lower abdominal skin and tissue. The lymphatics from below the belly button that would normally flow toward the lymph nodes in the groin are now replaced with upper abdominal lymphatics that flow toward the axilla. Without any or much liposuction, the lymphatic system essentially remains intact and does not have the “mechanical insufficiency" component caused by liposuction. If the incision is not extended too far past the mid trunk, it shouldn’t affect the lymph flow from the lower back region to the lymph nodes in the groin. In this case the recovery likely only involves the normal post-op fluid edema with a lesser possibility of more prolonged edema from significant lymphatic system damage. These cases would be much less likely to “need” manual lymph drainage, but it could be helpful in relieving pain and speeding recovery like after any surgery that causes post-op edema. We should also note that the different techniques available for liposuction also play a role in post-op swelling and recovery.
The VAIL Concept & Why?
The venous, arterial, integumentary, and lymphatic systems (VAIL) are interrelated. Anatomically, physiologically and biochemically, these systems work in unison to maintain homeostasis. Dysfunction in one system will lead to dysfunction in the other systems, and this may manifest sub-clinically or be overt. Edema is the clinical manifestation of either an overwhelmed or damaged lymphatic system. One is transient and the other is a disease. Both are part of the lymphedema continuum.
All edema is lymphatic fluid
Lymphatic impairment leads to local areas of compromised skin barrier function rending the skin more prone to breakdown and impairments (chronic wounds, infection). (5-7)
Called lymphatic dermopathy
Movement enhances VAIL by promoting more optimal functioning (effects on muscle pump, pumping of lymph nodes near joints from ROM, and support for vascular integrity and health).
The venous and lymphatic systems are mutually interdependent. When dysfunctional, the result is a dual outflow system failure.
Tri system failure with integumentary impairments (venous leg ulcers, dermatitis, etc.)
Disorders of the lymph system, whether systemic (macro-lymphedema) or localized (micro-lymphedema) produce cutaneous regions susceptible to infection, inflammation, and carcinogenesis (lymphatic dermopathy = skin barrier failure; tri-system failure). (5-7)
The pathophysiology of lymphedema explains the propensity for infections (cellulitis) and hypersensitivity reactions in patients with chronic venous insufficiency (lymphatic dermopathy).
A functional lymphatic system is essential to an organism’s overall health given its role in fluid homeostasis, removal of cellular debris, and mediating immunity and inflammation. (8)
Lymph Stasis = Chronic Inflammatory State
Stagnating lymphatic load or lymph fluid results in a pathohistological stage of chronic inflammation resulting in fibrotic changes, thickening, and connective tissue proliferation. “Oxidation & degradation of interstitial proteins attracts monocytes that change into macrophages. Macrophages ingest the proteins and activate fibroblasts that, in turn, form collagen resulting in connective tissue proliferation.” It also triggers adipocytes, leading to fatty tissue proliferation. (1)
Macrophages -> Fibroblasts -> Fibrotic Tissue
**There is no re-absorption in the blood capillaries. Fluid is returned to the venous system / vascular compartment by the lymphatics alone. ***
“Arguably, it may be better to consider the presence of chronic edema as synonymous with the presence of lymphedema, inasmuch as all edema represents relative lymph drainage failure.”
- Dr. Stanley Rockson, Stanford Medical Center
“…all edema indicates an inadequacy or failure of lymphatic drainage…” (9)
“…lymphatic failure is responsible for all forms of peripheral edema…” (10)
These statements represent a significant paradigm shift.
How is all Edema Lymphedema? Starlings Law Redefined
What about Starlings Principle of the Microcirculation?
Our previous understanding of Starlings Law regarding capillary fluid exchange is based on hydrostatic pressure which favors filtration of plasma OUT of capillaries and on osmotic pressure which favors osmotic movement of interstitial fluid INTO capillaries with about 90% returned at the venous end and 10% via the lymphatics.
Our new understanding is based on the Endothelial Glycocalyx Layer (EGL). This the the gel-like matrix with hair-like projections extending into the lumen of blood vessels. It acts as a molecular sieve regulating fluid and macromolecule movement. It allows for only a diminishing net filtration across the capillary bed. (11)
In 2010, Levick and Michel mathematically demonstrated that there is no net reabsorption of fluid back into the venous side of the blood capillaries. There is only diminishing net filtration across the capillary bed. (9)
Structure and Function of the Endothelial Glycocalyx
Hair-like projections are organized like bushes, with roots communicating with the base layer.
EGL is organized into a hexagonal matrix where blood flow shear forces act on the endothelial cells (mechanotransduction).
Vascular endothelial cells respond to the mechanical signals, producing and releasing Nitric Oxide which dilates the vessel. (11,13)
EGL sheds in response to inflammation, ischemia, sepsis, trauma, atherosclerosis, diabetes, intravenous fluid management as well as prolonged immobility. (11,14)
The EGL is dynamic and can “shed” in response to stimuli, such as during inflammation or disease states.
Shedding is conceptualized as a dog shedding its fur.
During inflammation, this shedding allows more fluid to escape through the EGL. (11,13)
The lymphatic system becomes overwhelmed leading to clinical edema. When you see edema, the EGL has been disrupted.
Key Lymphatic Considerations
The dense capsular design of the lymph nodes, placement in joint areas that are mechanically compressed by movement, and role of the EGL all work synergistically to facilitate fluid reabsorption back into the venous system via the lymphatics.
Conversely, immobility and decreased joint movement through the full range of motion, lymph node removal, or venous hypertension can have a significant impact on fluid retention in the dermis and subcutaneous tissues.
All fluid, proteins, and macromolecules are removed from the interstitium by the lymphatics alone (lymph capillaries, vessels, and nodes).
Lymphedema Risk Factors
Obesity
Chronic venous insufficiency
Post-thrombotic syndrome
Vein stripping or harvesting
Surgery (i.e. revascularization, TKA, THA, abdominal surgery, hysterectomy)
Decreased mobility
Congestive heart failure
Chronic kidney disease
Trauma
Scars
Burns
Lymph node dissection or removal
Radiation
Chronic wounds
Recurrent cellulitis
Congenital malformation of lymphatic vasculature
Tumors obstructing lymphatics
Travel to or living in Lymphatic Filariasis epidemic areas
Prolonged dependency of a limb or other body part
Hyperthyroidism
Medication with edema as a side effect
Chronic skin disorders and inflammation
Arteriovenous shunt (15,16)
Nutritional compromise
Fat disorders
Link Between Obesity and Lymphedema
There is an increase in multi-causal, obesity-related lymphedema
Why? Adipokines
Adipose tissue is an endocrine organ. It produces the hormone adipokinase.
Obese individuals suffer from greater immobility thereby a reduced muscle-pump which further impairs/impacts lymphatic function.
Overhanging abdominal wall can compress lymphatic and venous structures.
Obesity-Induced Lymphedema (OIL)
Obesity can cause lymphedema or worsen lymphedema.
A BMI threshold of 40 exists at which point lower extremity lymphatic dysfunction can occur.
The risk of OIL increases with elevated BMI. 90% of individuals with a BMI > 60 will have the disease (secondary lymphedema).
Patients with OIL, or at risk of the disease, are managed with weight loss.
Operative intervention to reduce extremity overgrowth is considered after patients have reduced their BMI to less than 40. (17)
CVI Pathophysiology and Phlebolymphedema
Etiology: Insufficiency of the venous system due to vascular failure of deep perforating or superficial veins.
Results in regurgitation of blood in the veins.
Creates dermal backflow of lymphatic fluid.
Impairs capillary function due to increased pressure.
This causes a dual outflow system failure and a tri-system failure with skin impairment.
Lymphatics are damaged from chronic venous insufficiency (CVI) and venous leg ulcers (VLU). (18,19)
All edema, including chronic venous insufficiency, is lymphedema beginning at stage C3:
Stage C0: No visible or palpable signs of venous disease
Stage C1: Telangiectasias or reticular veins, “spider veins”
Stage C2: Varicose (protruding) veins
Stage C3: Edema (fluid retention) visible
Stage C4: a. Pigmentation and/or eczema b. Lipoermatosclerosis and/or atrophie blanche
Stage C5: Healed venous leg ulcers
Stage C6: Active venous ulcers
How do we treat edema if it is all lymphedema?
Know the etiology or contributing factors for medical management.
What is the geography of the edema/lymphedema?
What is the patient’s vascular status?
What is the patient’s integumentary status (integrity, sensation)?
What is the patient’s functional status?