The venous system of the legs is made of veins embedded deeply and surrounded by strong muscle support, and surface veins embedded just after the skin - thin and delicate. It is on the surface veins that ugly, irregular balloon blisters, called varicose veins, form.
VIRUS, KEEP THE BLOOD TO THE HEART
The role of veins in the blood circulation
Tissues and organs, including energy-consuming muscle cells, receive oxygen and nutrients from arterial blood pumped through the heart. After using the resources of this blood in the so-called cellular combustion cells and tissues donate venous blood waste to decomposition of matter - carbon dioxide, urea, etc. This process of exchange is called microcirculation. Then, the deoxygenated and full of "dirty" metabolites, the blood goes to small veins, which fall into the larger veins leading, for example, from the legs "up", to the heart. In total, the venous system delivers about 7,000 liters of blood a day to the heart.
Two ways of venous blood from the legs to the heart
The leg venous system is composed of two parallel vascular systems.
1. The first are veins - deeply located, under the fascia covering the muscles of the legs. These veins, called deep or internal ones, flow from the legs to the heart about 90-95% of the blood.
2. The second way of blood to the heart is formed by surface veins, which, as their name suggests, run just below the surface of the skin of the leg.
The blood pathway inside the leg is well protected against damage
The veins are located in the vascular bundle between the leg muscles. In this bunch - deep veins and arteries are surrounded by muscles of the legs, which protects them well against injuries and protects against excessive expansion under the influence of blood pressure.
The surface veins do not support the muscle envelope
They run upwards on the surface of the leg, fixed only in the delicate adipose tissue. Thus, too much pressure of the blood pressed upwards relatively easily widens the thin walls of these vessels. The easier it is that the thin layer of the skin can not prevent injuries and damage to the surface veins.
The system of surface veins in the leg consists of a saphenous vein and a scapular vein.
Fig. 1.
The saphenous vein (1) is very long - it runs up the inner surface of the leg, from the foot to the groin. The shotgun (2) runs from the foot on the posterior surface of the shin and penetrates deep into the leg to form a deep vein
WHEN IS SPACE? BLOOD PRESSURE MECHANISM "UP"
Muscle-valvular pumps allow the return of blood from the legs to the heart
The rhythmic pressure of the leg muscles on the veins acts as a "plunger" of the pump. This is especially true for the deeply compressed large deep veins. Strained during movement or other physical effort, the muscles expanding in volume - push all the blood out of the contact vein towards the heart.
Squeezing the blood "up" thanks to the muscle pump allows venous valves.
Under the influence of muscle pressure and blood pressure - they drop and automatically block the "down" direction.
Microcirculatory disorders and venous diseases
Most circulatory insufficiency, due to diseases and heart failure, advanced atherosclerosis, venous diseases, etc. - secondary leads to blood stagnation in the veins and accumulation of excess tissue fluid around the venous capillaries. Their consequence is inflammation and perinatal edema. Venous pressure increases, venous valves are damaged. In advanced cases characterized by significant venous hypertension, arteriovenous fistulas with retrograde blood flow are opened. In the microcirculation this leads to the degeneration of arterioles and the formation of so-called capillaries. On arteriovenous fistulas with a backward flow of blood "down" the leg in the veins of calves and thighs leads to the formation of varicose veins.
When something starts to break in your veins
If blood can not flow to the heart in the simplest way, it retreats and bypasses the obstacle. Instead of a varicose vein clogged with a surface vein, which is just below the skin, it returns to the heart with deep veins. If the stabbing vessels - venous fistulas and deep veins are in working order; if their valves work well, in addition, the muscles of the legs support (massage) the walls of deep veins, this path is efficient and nothing bad happens. Problems start when one of these elements is damaged.
Other causes of poisoning
The walls of the veins lose their elasticity and thickness with age. It may cause damage to the venous valves. The passage of years, leg injuries, surgical operations, obstacles blocking circulation also contribute to the development of venous and varicose veins diseases. The tendency for varicose veins is often hereditary. Their creation may also contribute to pregnancy, onerous working and living conditions as well as standing or sedentary lifestyle.
The most important causes of varicose vein disease are:
1. Hereditary predispositions, inheriting defective venous valves, etc.
2. Frequent and long stay in a sitting or standing position
3. Overweight, flat feet and other posture defects
4. The influence of the endocrine system on venous vessels. The latter explains the development of varicose veins during pregnancy, during menopause, their more frequent occurrence in women and the tendency to venous thrombi as a result of hormonal therapy (HRT, contraception).
5. Obstacles in venous return - an obstacle in the form of a fibroma, clot in the small pelvis, etc.
6. Extrinsic factors such as: injuries of the body and veins, excessive effort, rapid heat (sauna, sunbathing, underfloor heating)
Causes of varicose veins and venous diseasesWhat to do when your legs swell?
ed. Edward Ozga-Michalski, MA
References 1.Chronic venous insufficiency. From the symptom and diagnosis to treatment dr med. Tomasz Zubilewicz, dr med. Jacek Wroński, prof. zw. dr hab. med. Jerzy Michalak from the Chair and Clinic of Vascular Surgery, Medical University of Lublin Head of the Department and Clinic: prof. dr hab. Jerzy Michalak; Medycyna Rodzinna - notebook 18 (2/2002) 2. Compensated and decompensated hemodynamics of venous circulation in the lower extremities Author: Dr hab. n. med. Zbigniew Rybak, prof. dr hab. n. med. Piotr Szyber, dr hab. n. med. Andrzej T. Dorobisz, MD Maciej Karasek, MD Mariola Oleszkiewicz, Esculap, 2005. 3. Preventive cardiology; editorship of prof. dr hab. med Marek Naruszewicz; Szczecin 2003, publisher of Verso s.c. 4. Troublesome varicose veins; bow. med. Marek Durakiewicz from the Department of Vessel Surgery SPSW im. Pope John Paul II in Zamość Branch Office: dr n. Med. Zbigniew Waga; Medycyna Rodzinna, issue 10 (2/2000) 5. Antithrombotic prophylaxis and treatment of thrombosis in various clinical conditions. Oral Anticoagulants, Antiplatelet Drugs - VI Guidelines of the American College of Chest Physicians. (2000) Medycyna Praktyczna ONLINE 2005 6. Varicose veins - prevention and treatment; Dr. Diner Reinharez, ed. WAB, 1993 / p. 58 /
