Vasc. U4(2) Lymph Formation FINAL PDF PDF

LYMPH FORMATION Vascular Pathology and Physiotherapy: Unit 4 (Part 2) UNIT 4 LEARNING OBJECTIVES  To be able to describe lymph and it’s contents  To understand how lymph is formed- Starling’s Law  To understand what oedema is  To be able to describe mechanical and dynamic oedema  To be able...

LYMPH FORMATION Vascular Pathology and Physiotherapy: Unit 4 (Part 2) UNIT 4 LEARNING OBJECTIVES  To be able to describe lymph and it’s contents  To understand how lymph is formed- Starling’s Law  To understand what oedema is  To be able to describe mechanical and dynamic oedema  To be able to describe potential causes of dynamic oedema  To be able to describe causes of lymphoedema (mechanical)  To be able to describe the classifications of lymphoedema, and sub classifications of primary lymphoedema  To be able to describe the potential causes of secondary lymphoedema  To be aware of lymphangitis and it’s pathophysiology KNOWLEDGE RECAP- PRESSURE CALCULATIONS & REASONS Filtration= Reabsorption= 1) Hydrostatic pressure at venous end of capillary = 31 2) Oncotic pressure at both ends of capillary = 7 3) Oncotic pressure at both ends of interstitial space = 12 Difference= In favour of: Filt / reab Filtration= Reabsorption= Difference= In favour of: Filt / reab Hydrostatic Oncotic TYPES OF OEDEMA Oedemas can be divided into one of two types Dynamic Insufficiency Mechanical Insufficiency MECHANICAL INSUFFICIENCY  Malfunction to the lymphatic system which limits fluid transport capacity  Therefore, mechanical insufficiency describes: OEDEMAS OF LYMPHATIC ORIGIN  Presence of oedema with high protein concentration  Evolutionary process of disease leads to chronic inflammation and fibrosis OEDEMAS OF LYMPHATIC ORIGIN Positive Stemmer’s sign Can be painless Principally no changes to skin colour More commonly unilateral Increased skin folds at joint line of affected area Commonly present dorsum of hand or foot OEDEMAS OF LYMPHATIC ORIGIN  ‘Malfunction’ refers to organic or functional defects of the lymphatic system  These malfunctions may be linked  Examples of organic (physical/structural) changes:  Filaments to lymphatic capillaries broken  Aplasia- lymph capillaries, collectors or nodes are missing  Hypoplasia- the diameter or number of collector vessels is below normal level  Hyperplasia- the diameter or pre collectors/early collectors is larger than normal  Examples of functional changes:  Spasming of smooth muscle layer within lymphangion  Valve insufficiency CLASSIFICATION OF LYMPHOEDEMA Primary Secondary PRIMARY LYMPHOEDEMA • Hereditary/congenital forms of lymphoedema • Underlying cause present at birth but symptoms apparent at differing ages • Due to triggering event/worsening condition causing lymphatic system to be overloaded • Localised lymphatic malformations • Due to malfunction at differing levels of lymphatic pathway • Affects 1 in 6000-10000 of population, all ethnicities PRIMARY LYMPHOEDEMA  Primary lymphoedema can be classified into 3 forms, determined by the age of onset of symptoms Congenital lymphoedema (Milroy Disease) Lymphoedema Praecox (Meige Disease) Alongside classification, symptoms of lymphatic disorder can appear in clusters with other symptoms, forming syndromes • Cutaneous-lymphatic-vascular alteration • Klippel-Trenaunay • Proteus • Polymalformative syndromes • Turner • Noonan Lymphoedema Tarda CONGENITAL LYMPHOEDEMA- MILROY DISEASE ▪ ▪ ▪ ▪ ▪ ▪ Genetic mutation Mutation is autosomal dominant 10-25% of all primary lymphoedema cases Symptom onset birth-1 year old Females > Males Causes bilateral lymphoedema in lower limbs (maybe most obvious at feet and lower legs, and scrotum) ▪ Causing aplasia or hypoplasia of vessels, with minimal collateral channels ▪ Accompanied by other symptoms such as upturned toenails LYMPHOEDEMA PRAECOX- MEIGE DISEASE  Genetic mutation, autosomal dominant  65-80% of all primary lymphoedemas- most common  Symptoms can onset birth - 35 years, but normally during puberty  Females > Males  70% of cases are unilateral  Left > right extremity  Lower limb > upper limb LYMPHOEDEMA TARDA  < 10% of primary lymphoedema cases- most rare form  Onsets after the age of 35 years  Likely hyperplastic malfunction- increased diameter of vessels, with functional disorder of ineffective valves CLASSIFICATION OF LYMPHOEDEMA Primary Secondary SECONDARY LYMPHOEDEMA  An acquired defect to the functioning of the lymphatic system  Therefore, no congenital abnormalities Examples of causes of secondary lymphoedema: • • • • • Trauma Surgical trauma Tumours Cancer radiation Lymphangitis (infection, usually if recurrent) • • • • Chronic Venous Insufficiency (CVI) Obesity Filariasis Lipoedema LYMPHANGITIS = Inflammation of the lymphatic vessel walls, normally due to infection within the lymph (originating distal to the affected vessel)  As well as being a cause of secondary lymphoedema, lymphangitis is a frequent complication of lymphoedema  Due to the mechanical insufficiency, the immune system is not as reactive when someone has lymphoedema, putting them further at risk of lymphangitis There are 3 common forms of lymphangitis:  Acute lymphangitis  Erysipelas  Dermatolymphangioadenitis (DLA) ACUTE LYMPHANGITIS  Local, non-systemic infection within the superficial lymphatic system  Commonly due to a bacteria, but can have other causes  Common example is normal skin flora of the patient accessing the lymphatic system  Symptoms include an increase in swelling and redness in affected limb  May have a tracking red line  In more severe cases may also include fever, vomiting and pain TREATMENT OF ACUTE LYMPHANGITIS  Early antibiotics (if bacterial cause identified)  Rest and elevation of the affected limb  Removal of compression garments (and K tape)  Avoidance of Manual Lymphatic Drainage  Improvements should be shown within 3-4 days  If no real change, assessment by doctor for consideration of intravenous antibiotics ERYSIPELAS LYMPHANGITIS= inflammation of lymphatic vessel, often acute, often due to bacterial infection. ERYSIPELAS= particular acute bacterial infection of lymphatic vessels.  Infection of superficial dermis  Extends to superficial lymphatic system  Caused by a bacterial infection (streptococcus)  Identified by having a very distinct border (much more so than differential diagnoses e.g. cellulitis/lymphangitis)  Bright red, firm, dimpled, painful  Most commonly affects legs, secondly face  Systemic effects: fatigue, fever, chills  Populations at risk: those with lymphoedema, older adults, babies DERMATOLYMPHANGIOADENITIS (DLA) Affects dermis Affects vessels Affects nodes  Infection of the subcutaneous tissues and superficial lymphatic vessels caused by ambient bacterial flora  Leads to inflammation of the vessels and lymphatic nodes in proximal direction of lymph flow  Can sit latent in the body, and therefore has the tendency to reoccur  Causes an increase in swelling to the affected limb and redness  Swelling often increases with each episode of DLA  Some evidence to support a decreased incidence, and duration of DLA with the adoption of daily foot hygiene and emollient application, compression (in moderate to severe cases), and exercises WHAT IS THE PATHOPHYSIOLOGY OF THE OTHER CAUSES OF SECONDARY LYMPHOEDEMA? • Trauma • CVI • Tumours • Filariasis • Cancer radiation • Surgical trauma • Obesity MATCH TO THE ANSWERS • • • • Trauma CVI Tumours Filariasis • • • Cancer radiation Surgical trauma Obesity  Crushing and burns damage or obstruct the lymphatic vessels, reducing flow.  This is commonly a cancer related treatment and involves dissection and excision which reduces the number of pathways available for lymph flow.  Malignancies can grow within or in close proximity to components of the lymphatic vessel system which obstructs flow and damages the vessels, which in turn can cause backflow.  This cancer related treatment can cause fibrosis of tissues, including lymphatic vessels, which impedes flow. MATCH TO THE ANSWERS • • • • Trauma CVI Tumours Filariasis • • • Cancer radiation Surgical trauma Obesity  With chronicity, the increased workload placed on the lymphatic system can cause insufficiency, this is called phlebolymphedema.  This leads to chronically increased lymph load which in turn causes insufficiency.  More common in Asia and the Eastern side of the world, this is a parasitic disease spread by mosquitos. The adult parasitic worm lives within the lymphatic system and impairs flow as well as damaging the vessels. The person can be treated with a year long course of medication, however the damage cannot be reversed. FILARIASIS https://www.youtube.com/watch?v=gMOGG_w1LeE THANK YOU https://www.lymphcareusa.com/professional/lymph-a-what/what-is-lymphedema/what-causeslymphedema.html https://emedicine.medscape.com/article/1087313-overview#a4 https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/starling-equation STAGES OF LYMPHOEDEMA