Definition
The lymph (lat. lympha = clear water) is a watery light yellow liquid, which is located in the lymphatic vessels. The lymph is a tissue fluid pressed out of the blood vessels.
The many individual lymph vessels and lymph nodes are collectively known as the lymphatic system and, along with the bloodstream, are the most important transport system in the human body. It serves primarily to transport nutrients and waste products. In addition, the cells in the lymph nodes in particular serve to defend against bacteria and other foreign bodies.
Properties of the lymph
Due to a pressure gradient, part of the blood plasma flows from the smallest blood vessels (capillaries) into the surrounding tissue and nourishes it. At the same time, this process serves to remove metabolic end products. Since the cells of the blood cannot penetrate the vessel walls, this tissue fluid consists only of water and dissolved substances.
About 90% of the tissue fluid then returns to the blood vessels with the substances intended for removal and is excreted via the kidneys. The remaining fluid is called lymph. It collects in the lymph channels and is then removed. In humans, about 2-3 liters of lymph are produced per day.
Lymph drainage areas
The lymph of the face is transported via fine lymph vessels in the direction of the neck and contains fluid from the tissue as well as waste products of the cell metabolism in the facial area. If the drainage is obstructed, swelling of the face may occur. Here, manual lymph drainage by an experienced physiotherapist can be very effective.
In addition, skin defects can lead to activation of the lymphatic system, which can also be accompanied by swelling of the local lymph nodes. These are located, for example, on the neck, in the back of the neck and on the lower jaw below the chin. The fine lymph drainage system of the eye absorbs the fluid between tissue and blood vessels and transports it towards the neck into larger lymph vessels.
Swelling in the area of the eyes, for example swelling of the eyelids, indicates a disturbed lymphatic outflow and can be alleviated by targeted massage in the area of the face by experienced physiotherapists. The lymph drainage of the ear flows into the larger lymph channels of the neck. The first smaller lymph nodes are located in the immediate vicinity in front of and behind the auricle.
If inflammation occurs in the area of the outer ear, these lymph nodes become swollen. Inflammations in the inner part of the ear drain into deeper lymph node stations. The lymph vessels in the neck are a special feature of the human body.
Basically, lymph flows from superficial pathways towards deeper lymph vessels. The connection between the superficial and the deep lymphatic system is particularly pronounced in the neck and in the armpit and groin region. The connection points have numerous lymph nodes, which effectively filter potential pathogens before they can penetrate the deeper system.
Infections in the neck region, such as tonsillitis or a cold, cause swelling of the local lymph nodes in the neck, which can then be easily palpated from the outside. Once the infection subsides, the swelling also goes down again. From an anatomical point of view, lymph nodes are always located in the catchment area of a particular organ and are often also affected by cancer.
If cancer occurs in the neck area, the lymph nodes must also be sufficiently removed in addition to the cancer focus. This is ensured by a so-called “neck dissection“. The lymph of the breast is closely connected to the lymph drainage of the armpit.
In the case of diseases of the breast, the lymph nodes in the armpit swell up quickly.The corresponding diseases of the breast include inflammation of the breast, lumps in the breast, but also cancer. If, for example, the lymph nodes of the armpit have to be removed as part of the therapy of breast cancer, there are a few things to consider. Clothing that is too tight should be avoided in order to avoid constrictions and thus a congestion of the tissue fluid.
Blood pressure measurements on the arm of the affected side should be avoided, as should blood samples. These measures prevent lymphedema of the arm. The lymph of the legs runs strictly along the vascular system in close proximity to the muscles.
Thus, their flow is particularly well stimulated by muscle activity. The muscles of the legs tense up when walking, the lymph is pressed head first in the lymph vessel and lymph vessel valves prevent backflow. The lymph of the legs flows in the groin region through closely connected lymph node stations.
In case of infections in the leg region such as infected wounds, these lymph nodes filter pathogens and swell. They are now very palpable and represent a clinical parameter for inflammatory activity. Lymphedema in the legs is particularly impressive, since an increase in circumference and size is often the first thing that stands out.
