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French cardiologists has published the results of studies that have shown that deep vein thrombosis was detected in 65% patients and 79% of patients transferred to the intensive care unit, and 94% of those who were in the ICU more than two days, despite anticoagulant prophylaxis
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Scientists study dangerous side effect COVID-19 – coronavirus causes the formation of blood clots in large vessels. Severe thrombotic complications occur in at least half of patients with coronavirus pneumonia, according to studies conducted by physicians of the Netherlands and France.
But practitioners are referred to more alarming figures. “There is a lot of research. Some of them indicate that 70% of critically ill patients with the coronavirus develop blood clots,” says Professor of medicine the London clinic King’s College Hospital Rupin Aria.
For example, the French cardiologists recently published in the journal JAMA Open Network results of studies that have shown that deep vein thrombosis was detected in 65% patients and 79% of patients transferred to the intensive care unit, and 94% of those who were in the ICU more than two days, despite anticoagulant prophylaxis.
Thrombosis can develop in just a couple of days and lead to death.
Researchers believe that thrombosis may explain why many patients with COVID-19 suffer not only from disorders in the respiratory system, but also lose their sense of smell, and also experience digestive problems and various malfunctions of the circulatory system.
Like other complications, blood clots develop from the overreaction of the human immune system to the coronavirus. Doctors-hematologists argue that not previously seen anything like it.
“Usually, the thrombus is part of the response of an organism to a small injury, but the reaction we observed in patients with COVID-19, just rolls. And thrombosis is observed not only in large and small blood vessels. The scale of the inflammation, which we have seen is that in addition to the usual blood clots in many patients formed blood clots in the smallest blood vessels. This applies particularly to the lungs, but also affects other organs – kidneys, heart, intestines…” – quoted by “Voice of America” Professor of King’s College Hospital Rupina Aria.
In many patients thrombosis develops rapidly. Blood clots formed in leg veins, causing thrombophlebitis; in the vessels of the brain, causing a stroke; in the system of coronary circulation (heart), causing a heart attack; in the lungs, causing pulmonary embolism; in the bowel, causing ischemia, etc.
“It is amazing how many manifestations of tromboobrazovaniu we see when COVID-19. And more amazingly, they are formed in young patients. And all this in the absence of primary lesions. Not even the usual atherosclerotic plaques,” – said Professor of Hematology at Harvard Medical School (institution of higher medical education at Harvard University) Robert Flaumenhaft.
Now anyone entering the hospital with COVID-19 in the United States try to give drugs to thin the blood such which are usually given to patients with stroke. But these anticoagulants increase the risk of bleeding, so doctors are urged to be careful – on the one hand need to be protected from blood clotting, on the other – do not cause bleeding.
One of the most popular blood-thinning medications – heparin. However, platelet insufficiency caused by heparin may spontaneously arise in patients with coronavirus infection even if they have never taken this drug. This fact also explains the high mortality rate of coronavirus patients.
The study showed, the body of patients COVID-19 produces antibodies to heparin. The result of the antibody attack not only heparin, but also platelets associated with it. Thus there is massive cell death, the formation of new clots and old ones dissolve. Amid coronavirus reaction develops spontaneously and immediately after the first administration of heparin. According to statistics, these complications are observed in 40% of patients in the intensive care unit with a severe infection. This applies particularly to patients connected to the artificial kidney. In this regard, physicians are encouraged to refrain from heparin using other thinning medications.
The researchers also found that the standard doses of blood-thinning drugs simply do not work – so thick becomes the blood of patients with coronavirus infection.
“According to studies using standard doses of anticoagulants in almost 50% of patients have large blood clots and potentially life-threatening blood clots. So in some hospitals, increase the dose of drugs, especially in patients with severe lesions that are in intensive care,” – said the Professor Aria.
In some patients there is a sharp increase in the blood level of protein, which is formed by the decay of blood clots (D-dimer). Its presence is a sign of the presence of probability of lethal outcome in patients with COVID-19.
“If the patient is prone to blood clots, if they already have a clot, the rate of this protein in the blood ranges from 0 to 200. And patients COVID-19 this figure is from 50 000 to 100 000, indicating a huge amount of blood clots,” says hematologist Jeffrey Lawrence.
These studies, published in the journal Nature, explain why patients with the coronavirus in weeks are on artificial lung ventilation (ALV). After all, even fed through them, the oxygen hardly penetrates into the blood due to a blockage of the blood vessels of the lungs.
“During the autopsies of deceased patients with COVID-19 we discovered the blood clots in the blood vessels, but found no other abnormalities characteristic of extensive pneumonia. The clinical picture was different: less inflammation, destruction of blood vessels, but significantly more blood clots,” – said Dr. Lawrence.
Doctors believe that blood clots often explains sudden death in patients COVID-19, as well as a sharp and sudden deterioration of their condition.
Since there is no cure for coronavirus no, scientists have to identify those who are most susceptible to the formation of blood clots.
Alas, the thrombosis is striking today about 70% of people. The development of thrombosis contributes to the defeat of the walls of blood vessels, increase blood clotting and slowing blood flow. Thrombosis may occur as a result of trauma of blood vessels, poor lifestyle and nutrition, due to the constant anxiety and stressful situations. At risk are the following categories of people: men aged 40 years; women older than 50 years; people suffering from obesity; patients with malignant tumors, are diagnosed with deep vein thrombosis (DVT) and pulmonary embolism (PE); people who have had extensive surgical intervention; patients on hormonal drugs; people who abuse alcohol, smokers, etc.