[Translate to Englisch:] Thrombose
Thrombosis
The thrombosis is a disease of the vessels where blood clots are formed in a blood vessel. Even though thrombosis can occur in every vessel, colloquially a thrombosis in the deep veins- phlebothrombosis- is meant.
Symptomathology
Symptoms can differ referring to the kind and the size of the thrombosis, many thromboses are not even recognized by the affected people. Especially critical of the diagnosis is that even severe thromboses which can lead to pulmonary embolisms proceed symptom-free in advance and can not be detected.
At least distinct venous thrombosis is typical:
- swelling and a warm feeling of the affected part of the body
- reddened and tense skin, possibly bluish skin
- feeling of tension and pain in the foot, calf and the hollow of the knee (relief when feet are put up)
Vein thromboses concerns predominantly the legs and the pelvis, the arms and the pectoral girdle are rarely concerned. A deep vein thrombosis means that low lying veins that directly lead to the heart are problematic. To dissociate shallow thromboses are called thrombophlebitis. Varicose veins often cause those. Shallow thromboses can “grow” deeper or can be flushed into the vein system so that it can become a deep thrombosis. When there is any suspicion for a thrombosis a visit at a doctor is absolutely necessary.
Diagnosis
To diagnose a vein thrombosis assuredly an ultra-sound (double sonography) and phlebography (X-ray with contrast medium) is used. If there is a modern ultra-sound instrument and the examiner is experienced enough, the complex, and for the patient burdening examination, only has to be performed in rare cases. Fibrin split products, a degradation product of thromboses can be attested in the blood with a D-dimer test (?). It is safe to say that with a sensitivity of 95% a negative D-dimer Test with a simultaneous low risk-score after Wells eliminates the possibility of a leg vein thrombosis. Arguably, the accuracy of the D-dimer test is less than perfect. Therefore, D-dimer does not necessarily always diagnose thrombosis appropriately.
Complication: a feared complication is an embolism.
A thrombus that breaks away from its point of formation and is washed into the blood blow through the body is called an embolus. If the embolus blocks a narrow place of the vessel system the tissue of the affected spot is not sufficiently supplied with blood any more and damage is caused, an embolism occurs.
Especially threatened by embolisms after a vein thrombosis are the big and small vessels of the lung (pulmonary embolism) because the lung gathers and filters all the blood of the venous circulation system.
Causes of the development of a venous thrombus are (Virchowsche Trias)
-coagulapothy
- intensive blood clotting attributable to heredity or caused by medication; diminished ability to disolve blood clots, e.g. APC-resistance or coagulation-V mutation (fibrinolysis)
- certain nourishments or toxins that have an influence on the blood clotting
- pregnancy
- dehydration
-potential situations that can cause a severe slowdown of the blood stream (stasis):
- enlarged veins (varix) or varicose veins
- jammed extremities caused by external pressure
- not enough opportunities to move because of bedriddenness (after surgeries or because of casts)
- narrowly sitting for a long time (airplane/bus) in addition to other risk factors
- damage of the inner vessel wall (intima)
- damages caused by traumas (injuries, bruises, surgeries)
- degenerative changes (eg. age-related)
- inflammable changes of the vein
- diabetes
- hypoxmian wall damages caused by carbon-monoxide (smoking) are controverted
Risk factors
- unhealthy lifestyle like smoking, overweight or physical inactivity
- hereditary or acquired coagulopathy (eg. lach of synthesis when cirrhosis of liver)
- pregnancy or the intake of oral contraceptives (“pill”)
- lack of exercise during long flights or travelling by bus (in common parlance “economy-class-syndrom”) or because of plasters
- confinement in bed: patients who spend less than 6 hours per day outside of bed have a statistically higher risk of thrombosis
- body fluid deficit (exsiccosis) that lowers the blood flow
- affected with cancer
- a broad hint for a higher risk of thrombosis is usually the appearance of thrombosis in the past
Therapy
Especially to avoid embolism patients are dosed with medicine to thin down the blood- in Germany usually Marcumar. In the course of this a positive effect can be the regeneration of an untroubled blood flow. The thinning of the blood with drugs that was still practiced in the 90s of the last century will only be applicable in very rare cases of venous thrombosis in the future because of a higher risk of hemorrhage. Also the removal of venous thrombes by surgery is only practiced in special cases. A vascular substitute for impassable or destroyed veins is very difficult because of the structure of tissue of veins and it is only performed in exceptional cases.
Prevention: The most important prevention is exercise since the activity of the muscle (e.g. legs) supports the venous reflow (muscular pump). If exercise is not possible patients at a risk should wear elastic stockings. They support the veins with a higher pressure on the tissue from the outside what eases the circulation of the blood.
Travelling thrombosis: During long-distance travelling you should get up as often as possible, move the legs, drink a lot and avoid alcohol (alcohol dehydrates). Persons with a high risk of leg vein thrombosis wear elastic stockings and take an inhibitor for coagulation, especially heparin, that can be injected yourself. Still the intake of acetyl-epsilon-aminocaproic acid (ASS- Aspirin) is suggested even though there is no effect on thrombosis since the acetyl-epsilon-aminocaproic acid only affects the blood platelets that do not cause venous thrombosis. Medication based on ASS should not be taken in combination with inhibitors for coagulation, like heparin, Marcumar or falithrom, since the effects interact and the inhibition of coagulation becomes beyond one´s control. As a long-term prophylaxis a patient at risk can take inhibitors for coagulation like heparin or coumarin, e.g. “Marcurmar”.
The consequence of a deep thrombosis can be the so called post-thrombotic syndrome (PTS). Veins affected by thrombes can keep impassable, building-up collateral circulations near surface can expand like varicose veins. Very often the venous valves are destroyed or its function is limited due to the cicatrisation what causes a stronger reflow of the blood against gravity. Because of the chronic abundance of blood vessels of the concerned extremities are overly widened. These physical factors are measurable at an examination of a specialised doctor (phlebologist).
The patient can slow down the appearance of PTS or can lower its impacts by:
Getting a lot of exercise for the concerned extremities thereby stimulating the circulation of the blood. This can be achieved through sports, especially those that enable a non vertical position should be preferred (swimming, bicycle, especially the recumbent bike).
Constant compression of the concerned extremities by wearing elastic stockings to equalize the high pressure of fluidity in the tissue and to increase the blood flow.
Avoidance of sitting or standing for hours, constant pauses by vein gymnastics.
Whereas commercially available “vein-strengthening” products- often on the basis of chestnut- turned out to be ineffective.