Despite the absence of high-quality data, in separate reports the thromboembolism phenomena at critically sick patients with COVID-19 are described. In a number of the centers with the growing experience in the sphere of treatment of COVID the guides to performing system anticoagulating therapy were developed. At the moment accurate proofs that anticoagulating therapy at sepsis or septic shock improves rates of mortality no.
Nevertheless, the large number of cases of trombotichesky complications at a new koronavirusny infection is described. In this connection antitrombotichesky therapy for these patients is strongly recommended.
At patients of standard risk performing prevention of a deep vein thrombosis according to the adopted guidelines by means of unfractionated heparin for hypodermic introduction or low-molecular heparin is strongly recommended; attention at the same time has to be paid to the correct dosage calculated taking into account weight at obesity or morbid obesity. For simplification of introduction it is recommended to use low-molecular heparin.
For patients of the increased risk, with signs of inflammation, for example, of quickly increasing D-dimera levels, S-jet protein or ferritin, it is recommended to increase a dose of low-molecular heparin for prevention of a deep vein thrombosis.
Infusional administration of heparin has to remain tactics for treatment of the patients entering into group of high risk. The initial target value of an indicator Xa has to be low, about 0.2-0.4. Monitoring by means of the activated partial tromboplastinovy time (APTT) can be unreliable as the AChTV basic value often is raised. Separate proofs demonstrate that maintenance of a condition of patients with COVID-19 within therapeutic range is difficult. It is worth paying attention that the level of triglycerides> 600 can affect results of the chromogenic analysis and it is wrong to overestimate indicators of anti-Xa. If at the patient the level of triglycerides is increased, it is more preferable to use enoksaparin instead of heparin.
It is necessary to avoid use of new oral anticoagulants for therapy of critically sick patients, considering lack of widely available drugs of retroaction.
It is not recommended to use a fabric plasminogen activator for treatment of COVID - the associated thrombosis if only it is not used according to other indications (a stroke, a massive thrombembolia of a pulmonary artery, etc.). Use of a fabric plasminogen activator in cardiac standstill cases when the probability of the preliminary diagnosis of a thromboembolism of a pulmonary artery is high, has to be considered in lower dosages.
Before strengthening anticoagulating therapy without proof of a thrombogenesis, it is necessary to execute the patient's assessment regarding risk of development of bleeding.
The analysis of the retrospective data obtained from China shows increase in rate of mortality among patients who do not undergo therapy by means of preventive doses of heparin or low-molecular heparin, especially among persons with the D-dimera level, exceeding the upper bound of norm more than by 6 times. It is well known that system inflammation can activate alarm functions of a thrombogenesis though the specific therapeutic techniques aimed at elimination of this problem did not lead to improvement of clinical indicators.
For lack of these observation and prospective clinical trials concerning COVID-19 and thrombosis, many authors consider that it is impossible to recommend anticoagulating therapy absolutely for all patients. Taking into account it it is necessary to pay attention to the following specific clinical characteristics which can be the indication for purpose of anticoagulating therapy in the absence of contraindications. The need for an intensive care in itself does not mean need of performing medical anticoagulating therapy, but it is possible to consider a question of strengthening of prevention or anticoagulating therapy for patients without considerable danger of developing of bleeding in the conditions of significantly the raised inflammatory markers.
If the question of performing anticoagulating therapy is considered, it is more preferable to use not low-molecular heparin, but unfractionated heparin as it is reported about its ability to connect and neutralize inflammation mediators and also about the dynamic nature of clearance of creatinine at a critical form of a disease.