Often underestimated: thrombosis

It’s terrible enough lying in bed sick. And here, in addition to the actual disease, there is a great danger: thrombosis. People who sit for a long time and a lot also have an increased risk of thrombosis. Overall, about two out of every 1,000 people in Western countries get a thrombosis every year. These blood clots tend to form in the deep leg and pelvic veins, more rarely in the arteries. There is an increased risk of thrombosis even weeks after surgery, especially in older patients.

Blood coagulates – fortunately.

Were it not for the fantastic ability of blood to clot, we would bleed to death from the slightest injury. The body treats internal and external injuries at lightning speed by constricting the blood vessels and then attaching the blood platelets, the thrombocytes, to the edge of the vascular injury. Together with numerous coagulation factors in the blood and tissue, they close the wound.

However, this protective mechanism has the opposite effect in certain diseases when blood in the body, more precisely in the vascular system, coagulates. This can lead to a blood clot, a so-called thrombus, forming in a vessel. The thrombus can completely seal the vessel – no blood flows at all. But when blood stops flowing, the supply of oxygen stops. The result is that tissue dies, and specific organs may even fail.

 

The veins are particularly affected.

The veins are primarily affected by thrombosis. Veins are the part of the blood vessel system that carries oxygen-poor blood back to the heart. From there, it is pumped through the lungs and then through the arteries back into the systemic circulation to supply all organs with oxygen again. Unlike the arteries, the veins have valves that are very important for transporting blood to the heart. In most cases, the valve pockets of the calf veins are the thrombosis’s starting point.

Everyone is familiar with one type of blood clot: varicose veins. These are dilated veins just under the skin. One in five Germans suffers from it; mainly, it affects women. If a blood clot forms there, it is usually harmless.

Symptoms of thrombosis

The symptoms of venous thrombosis are severely painful swellings in the leg, which usually feel overheated and turn blue. Read here how to recognize a thrombosis.

Due to the constant congestion of blood, a chronic venous disease can develop – often with leg ulcers ( ulcus cruris).

 

Embolus: When a thrombus migrates

However, a thrombus can also be carried away by the bloodstream and become a “wanderer”, the embolus. It is washed away from the point of origin and occludes a vessel elsewhere – resulting in a life-threatening embolism.

We want to prevent this at all costs. This is where the “anticoagulants” come into play. Various coagulation factors in the body are named with Roman numerals in the order in which they were discovered.

anticoagulant factors

The coagulation factors are blood proteins and are formed in the liver. Anticoagulants delay blood clotting by reducing the body’s production of specific coagulation proteins. The clotting time is specifically extended, and the formation of unwanted clots, which can block a blood vessel, is prevented.

For example, patients with artificial heart valves have to take the active ingredient coumarin. Patients who have to lie in bed for a long time because of an operation are given unloved thrombosis stockings and daily heparin injections.

Heparin and thrombosis stockings

Heparin is a drug that stops blood from clotting and is injected just under the skin. Patients who have to lie down a lot at home because of a broken leg, for example, inject their medication themselves – usually in the abdominal wall below the navel.

The intake of acetylsalicylic acid is repeatedly recommended, but its effectiveness in preventing traveller’s thrombosis is disputed since it only affects the arteries and not the veins.

Thrombosis stockings, or compression stockings, are used preventively: They support the veins through increased tissue pressure from the outside, facilitating blood return. They are also recommended for high-risk patients embarking on more extended air travel.

 

treatment of thrombosis

Treatment of thrombosis should be given as soon as possible to prevent further progression of the thrombosis and to reduce the risk of complications, which can be life-threatening. Bed rest in the case of thrombosis from the hollow of the knee upwards, while activities such as walking around are among the first measures in the case of thrombosis in the lower leg veins.

The legs are wrapped with bandages until the swelling subsides, after which a compression stocking must be worn. Blood flow can be restored by dissolving the thrombus with medication.

Large blood clots can also be removed surgically; sometimes the blocked section of the vessel is bridged using an angioplasty, the so-called  bypass .

Risk factors for thrombosis

The following factors mean an increased risk of thrombosis:

• prolonged bed rest
• Lack of exercise, such as sitting for long periods on long-distance flights or in the car
• Lack of fluids
• congenital coagulation disorders
• increased blood clotting tendency after major operations or childbirth
• Arteriosclerosis  and varicose veins, often in old age
• Women taking the contraceptive pill
• Pregnancies
• overweight
• Smoking