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Unit 8: Authorised Assignment Brief for Learning Aim B – Physiology of Human body. Lymph Vessels The lymphatic system spreads widely across the entire body and is made up of many different parts, those parts consist of the lymph vessels, lymph nodes, valves, thymus gland, tonsils, lacteals, and the spleen. The lymph vessels are thin-walled and valved, they are with endothelial cells and consists of a smooth, thin muscle wall and the outer wall binds the vessels to tissue that surrounds it. The endothelial is simple squamous epithelium, which has a highly permeable membrane, it also has junctions where the endothelial cells over-lap each other on these vessels in order to allow lymph in but not out. The smooth muscles bellow them are in a circular fashion and allows for the lymph to be pumped slowly around the body, and is involved with vasoconstriction and vasodilation, vasoconstriction increases blood pressure and vasodilation is the dilation of blood vessels, which decreases blood pressure. The outer layer is known as the adventitia and made out of collagen mostly and mainly acts to hold the lymph vessels stable within the body, but not all vessels contain the adventitia. Much like the vessels that transport blood around the body in the circulatory system, the lymph vessels transport lymph around the body, it carries it from the tissue through the lymph nodes and delivers cleaned fluids back to the blood. The lymph travels through the vessels due to smooth muscles, valves, and compression when the adjacent skeletal muscle and arterial pulsation compresses. Lymph Nodes Lymph nodes are small glands that are bean shaped. They are split into nodules and each nodule contains an outer cortex and then a paracortex, with the medulla inside. They are surrounded in connective tissue; this creates the capsule. The nodules are the store for the P-cell and T-cell lymphocytes and white blood cells are stored in its medulla. There are five major nodes known as axillary, supratrochlear, abdominal, inguinal, and popliteal nodes. Nodes can be found in all areas of the body other than the central nervous system. They filter lymph fluid and then return it to the blood, they maintain blood volume and pressure, defend against infection, and prevent fluid build-up in tissues. Axillary Nodes: The axillary nodes are located in the armpit and its main role is to perform filtration and conduct lymph. These nodes can be split into five different groups: the pectoral, lateral, subscapular, central, and subclavicular. Each of these nodes are all important in the transportation of nodes. The pectoral groups are made of four or five nodes in the superior border of the pectoralis. The afferent vessels send lymph too these nodes and efferent vessels carry lymph away from these nodes to the central lymph node. Lateral group boarders the lateral edge of the pectoral group and consist of between four and six different nodes that cluster around the axillary vein. Lymph from the upper arm flows into the lateral group and then into the central lymph nodes via the efferent vessels. Subscapular groups are located in the back of the shoulder blade and consists of six to seven nodes. It filters the lymph from the back of the neck and upper back. Efferent vessels take the lymph from them into the central lymph nodes. Central nodes consist of three or four nodes within the adipose tissue in the bottom of the axilla. They further filter the filtered lymph from the pectoral, lateral, and subclavicular nodes. The lymph from there is then taken to the subclavicular node bellow the collar bone. The subclavicular node is composed of between six and twelve nodes and they are the final filtration process the lymph goes through before going on to the subclavian trunk. These different groups are all regions that make up the axillary node.
Supratrochlear Node: The supratrochlear node is located within the elbow and consists of two nodes. There afferent vessels work to drain the forearm, hand, ring finger, little finger, and middle finger. There efferent vessels join the deeper vessels and are alongside the basilic vein. The lymph drained is then filtered in the supratrochlear node and is then sent to the lateral group of the axillary node where it is further filtered. Cross drainage in these vessels is possible as they are in free communication from other vessels in the forearm. Abdominal Nodes: The Abdominal nodes are sorted into two different groups: The superficial group and the deep group. The superficial group is the first drainage point of the abdominal wall and the deep groups work to send the lymph from the superficial group into the abdominal viscera, of which they are usually associated with, and the superficial group is associated with the subcutaneous blood vessel, the lymph from the superficial abdominal node is drained into the superficial inguinal nodes. The abdominal region can be split into the upper and lower abdominal wall, the deep abdominal nodes drain from the lower abdominal wall into the circumflex iliac. The drainage point of the adnominal viscera would mainly be through the thoracic duct. Inguinal Nodes: Inguinal nodes have two layers that are below the inguinal ligament, this runs from the largest bone at the front of the ilium to a bottom centre of the pelvis in the public region. The two layers are the superficial inguinal nodes and the deep inguinal nodes. The superficial inguinal nodes are located in the upper, inner thigh and consists of ten nodes and drains into the deep inguinal nodes. The deep inguinal nodes are located below the connective tissue of the upper, inner thigh along with being on the medial side of the femoral vein and consists of three to five nodes. There is also another type of inguinal node known as the Cloquet’s node and it is the top-most deep inguinal node and is below the inguinal ligament. These nodes work to drain the lymph into the external iliac node, then the pelvic node and finally, the paraaortic nodes. These nodes still do the same basic function that all nodes do which is to filter waste, maintain fluid balance in the bloodstream, and help play a role in immune defence but inguinal nodes main purpose is to drain the reproductive organs and the bladder as well as the pelvic region. Popliteal Nodes: Popliteal nodes are located behind the knees and consists of six or seven nodes, and they work on the lower legs, feet, and toes. Most people have between two and nine popliteal nodes that form as a big cluster. There are two sets of popliteal nodes known as: the deep popliteal node and the superficial popliteal node, the deep popliteal node is located close to the popliteal vessels and the superficial popliteal node is located with the small saphenous vein. The superficial and deep popliteal nodes drain lymph from the toes, feet, and legs and then the popliteal nodes drain the lymph from those, sometimes on rare occasions even draining the overlying skin. These nodes also do the same filtration and balancing as all of the other nodes. Valves: The valves are one of the lymphatic vessel’s main features, they are semilunar valves that are attached to sides of the endothelium. They are only located in the larger lymph vessels along with the collecting vessels but would not be found in the lymphatic capillaries. The role of the valves is to prevent backflow of fluid so that the lymph will be flowing forwards instead of falling backwards.
and becomes significantly
bigger when you are ill or injured. The spleen has a main job of filtering the blood and it manages the number of red blood cells carrying oxygen around your body and the number of platelets, this is achieved as the spleen breaks down abnormal, old, or damaged cells and it also removes them. The spleen also produces lymphocytes whenever it detects viruses, bacteria, or any other germs in your blood in order to help fight off infection. Lymph & Lymph Formation Lymph: Lymph is formed from interstitial fluid which surrounds the body cells. When arterial blood enters the arterial capillaries most of it will flow into the venous capillaries and some of the blood plasma escapes and forms interstitial fluid around the body cells, this is where it picks up waste products, tumours, bacteria, and toxins. When the interstitial fluid enters the lymphatic capillaries, it then becomes lymph, this process is known as lymphogenesis. The role of the lymph is to destroy dangerous bacteria and cancer cells along with filtering waste and toxins. The lymph also works alongside the circulatory system to assist in delivering hormones and nutrients to the tissues of the body. This lymph is transported via a system of vessels, and the flow is controlled by muscle contraction, which moves the lymph forward through the system, and valves, which prevent lymph from flowing backwards. The lymph travels around the body and foreign materials are removed in the lymph nodes and when filtered is sent back into the blood stream. Lymphocytes: Lymphocytes are the immune cells and can be found in the blood and lymph nodes, there are two main types of lymphocytes known as B lymphocytes and T lymphocytes. Lymphocytes are created in the bone marrow; the bone marrow creates stem cells which can turn into any type of white blood cell but most commonly turn into T and B lymphocytes. 25% of lymphocytes remain in the bone marrow and mature to become B cells and the 75% of lymphocytes will travel to the thymus where they mature and become T cells. The bone marrow will undergo a process known as haematopoiesis which is where the stem cells differentiate into several different kinds of blood cells. This is where are lymphocytes originate from, then they again differentiate further into specific types of lymphocytes, this whole process is called lymphopoiesis. The main job of the lymphocytes is to bind themselves to antigens and remove them from the body. Lymphocytes travel around the body in the lymph fluid and the leave the node via efferent vessels in order to travel to different parts of the body and perform adaptive immune response functions. The process of the lymphocytes is very important as they ensure that the body is kept safe and healthy, working with the rest of the immune system to ensure nothing that may harm us stays inside us. Interstitial Fluid: The interstitial fluid surrounds the cells of our body and if it were not removed different areas of the body would start to swell up. The lymphatic system actively works to remove this fluid, preventing this from happening by returning it to the blood plasma. Once the fluid enters the vessels it then will contain many different cells and other substances that will help with immune response. It does this by letting white blood cells to locate and destroy any harmful bacteria or viruses that had infected cells. Metabolic waste also tends to be removed into interstitial fluid by cells and the waste is then cleaned throughout the lymphatic system.
Treatments: Lymphoedema is an uncurable disease but there can be types of treatment to help reduce its affects. There are two common types of procedures that can be used: Pneumatic compression which is an inflatable sleeve which puts pressure on the affected limb to try and push the lymph away from the affected area. In cases of severe lymphoedema then lymphoedema surgery is another procedure that can be considered. There are a few different procedures that you can undergo some of those being Liposuction, this is used when lymphatic fluid begins to spill into your surrounding tissues causing inflammation and fat stems cells begin to grow, the process involves your surgeon removing the extra fat, usually resulting in short recovery time and an outpatient procedure. Another is lympho-venous bypass/lymphatic venous, this is when the surgeon uses microsurgical techniques and equipment in order to reroute your lymphatic system, this includes bypassing damaged nodes and directly connecting lymphatic channels into your veins, this is also an outpatient procedure and has a quick recovery time. Lymphovenous transplant is another form of surgery that can be used, this will involve transplanting a group of healthy nodes from one part of your body to the affected area, basically rewiring your system, this procedure is an inpatient one and recovery time can be up to a few days. A skin graft is also possible treatment that can be used, this can also be known as debulking and can be used for small cases as well as severe ones this involves removing the affected tissue and using part of a skin graft to repair that area, this procedure will take up to a month in recovery time and will need more extensive care on site after the surgery. Therapy is another method that can be used to help reduce the disease; massage therapy is one of these types of therapy. Massage therapy is used to help fluid movement out of the limbs, this is a manual lymph drainage which can encourage lymph fluid flow from the arm or leg, however, this is not recommended if you are already suffering with blood clots, skin infections, or an active lymph disease in the drainage areas involved. Another method is complete decongestive therapy (CDT), includes a combination of therapies which includes lifestyle changes. The final type of therapy being physical therapy simple exercises that help movement of the affected limbs and cope with everyday activities by wrapping a bandage around the affected limbs. You can also practise recommended exercises in order to reduce stress, these include simple exercises that will help the protein to be reabsorbed from the lymph fluid which can diminish arm lymphoedema symptoms. Another exercise is called ball squeeze, this is a seated exercise and is a good way to slowly work your way into other exercises. Elbow flexion is another exercise which is completed whilst sitting and it uses your upper arm muscles to release stress on your axillary lymph nodes. Elbow extension is a floor exercise and can be done with both arms and works the muscles in your upper and lower arm as a form of releasing stress on the nodes in those areas. It is also a good idea to avoid foods with high sodium content, processed dairy products, carbonated drinks, and processed grains. Also try to eat foods with high protein content and increase your intake of fruit and vegetables, keeping to this diet and lifestyle can help to adhere to an anti-inflammatory way of going about your day and being able to combat the inflammation so that it does not affect you as much. Benefits & Side-effects: Whilst there are obvious benefits from using these treatments some of these treatments can also lead to some risk/side-affects. Compression has the obvious benefit of maintenance therapy for lymphoedema along with causing a decrease in pain and discomfort and the pneumatic compression mimics the lymphatic system in order to decrease the discomfort, but it also has the chance of causing a number of side-affects that may not be a huge risk but are still risks none the less. It can
cause a mild skin rash in the area that it has been treating, discomfort and sweating beneath the cuff, skin breakdown, and in some rare cases can cause nerve damage or pressure injury. Physical therapy is another example of a treatment that can come with both benefits and risk, physical therapy’s main benefits are to decrease the swelling caused by lymphoedema and the other is an improved range of motion, this means that you will be able to move your joints easier and further than you usually can. Physical therapy can also help to improve the quality of your sleep, alleviate headache tension, and help with stress whilst helping to treat your lymphoedema by reducing the build-up of lymph fluid. However, it can also cause a temporary soreness, low blood sugar levels, bruising, allergic reactions, and in some cases if a patient is already suffering with an ongoing bone disease, can cause fractures. Massage therapy may be helpful but has a small number of side-effects the two main side-effects from this are nausea and vomiting and sometimes bruising can occur in areas where firm pressure has been applied, although, diabetics may have an increased rate of side effects due to the massage therapy possibly having an effect on their blood sugar levels. Lymphatic surgery is usually a last resort as it is always best to stay away from doing surgery unless necessary with anything not just lymphoedema, the side-effects of lymphatic surgery however, can include limited movement in the affected area after the surgery along with numbness of the skin because the nerves that controls sensation travel through the lymph nodes area, in worse case scenarios, by performing lymph node surgery it can very rarely case lymphoedema to occur in a new area where the nodes have been moved from, giving this form of treatment another reason to be last resort. Overall, the best treatment for lymphoedema is the decongestive therapies such as compression, exercise and dietary changes, although these methods may time more time and more effort, they are the treatments with the least risks and side-affects and are very affective forms of treatment. These treatments are also the most commonly recommended forms of treatments by doctors for the same reason that they are most effective foe keeping lymphoedema under control. Bibliography A Bradford. (2018). Tonsils: Facts, Functions & Treatment. [Online]. LiveScience. [Viewed 22 March 2021]. Available from: Tonsils: Facts, Function & Treatment | Live Science BD Editors. (2017). Interstitial fluid. [Online]. Biology Dictionary. [Viewed 28 March 2021]. Available from: Interstitial Fluid - Definition and Quiz | Biology Dictionary Dr AP Singh. (2021). Supratrochlear Lymph Nodes. [Online]. Med Care Tips. [Viewed 18 March 2021]. Available from: Supratrochlear Lymph Nodes | medcaretips.com Dr C Troup. (2020). The hydrostatic pressure: General Principles, Application in medicine and differences with oncotic pressure. [Online]. Scope heals. [Viewed 01 March 2021] Available from: The Hydrostatic Pressure: General Principles, Application in Medicine and Differences With Oncotic Pressure - Scope Heal Dr M Hardy. (2020). What do tonsils do? [Online]. Patient. [Viewed 24 March 2021]. Available from: What do tonsils do? | Adenoids Function | Patient Dr M Hardy. (2020). What do tonsils do? [Online]. Patient. [Viewed 24 March 2021]. Available from: What do tonsils do? | Adenoids Function | Patient Dr R Miller. (2021). What is the role of lymph in my body? [Online]. Sharecare. [Viewed 26 March 2021]. Available from: What is the role of lymph in my body? | Immune System - Sharecare Healthline Editorial Team. (2018). Inguinal Lymph Nodes. [Online]. Healthline. [Viewed 19 March 2021]. Available from: Inguinal Lymph Nodes Anatomy, Diagram & Function | Body Maps (healthline.com)
Healthline. [Viewed 27 March 2021]. Available from: Lymphocytes: Definition, Counts, and More (healthline.com) T Taylor. (2015). Popliteal Nodes. [Online]. Innerbody research. [Viewed 20 March 2021]. Available from: Popliteal Nodes (innerbody.com)
T Taylor. (2017). Axillary nodes. [Online]. Innerbody research. [Viewed on 17 March 2021]. Available from: Axillary Nodes - Anatomy Pictures and Information (innerbody.com) The editors of encyclopaedia Britannica. (2020). Lacteal. [Online]. Britannica. [Viewed 24 March 2021]. Available from: Lacteal | anatomy | Britannica The editors of encyclopaedia Britannica. (2020). Lymphocytes. [Online]. Britannica. [Viewed 27 March 2021]. Available from: lymphocyte | Description & Functions | Britannica The NHS. (2019). Lymphoedema. [Online]. NHS. [Viewed 30 March 2021]. Available from: Lymphoedema - NHS (www.nhs.uk)
