Yang X. Venous thromboembolism in surgery of abdominal organs: clinic, diagnostics, treatment and prophylaxis

In this thesis the results of perioperative risk factors study, clinical and laboratory criterias of venous thromboembolism in abdominal surgery are presented; the seasonal variations of the thrombotic complications frequency, the parameters of coagulation changes depending on the time of year in surgical patients are analyzed, the effectiveness and safety of various treatment regimens, prevention of venous thromboembolism in the postoperative period on the background of the factor Xa inhibitors, low molecular weight heparin, Vena cava filters usage in compared to classic heparin therapy are also assessed. In clinical follow-up was found, that the main prognostic factors in the origin of venous thromboembolism are the female sex, the age of patients more than 60 years old, with the presence of additional linear 5-year trend (р<0,05). Also previous diabetes mellitus of 2 type, ischemic heart disease, chronic heart failure are associated with the risk of thromboembolism in abdominal surgery. In thesis, we proved the influence of 3 or 4 category of surgical interventions by NCEPOD scale and the dependence of duration of intervention on thromboembolic outcome after abdominal operation. It was established that some laboratory parameters are reliably associated with the increased incidence of venous thromboembolism; which are - decreased of the antithrombin III and protein C activity, the growth of spontaneous platelet aggregation, shortened lag-phase of collagen-induced platelat aggregation, irreversible of ADP-induced platelet aggregation. It was verified that seasonal changes in the platelet hemostasis are characterized for the 4th quarter of the year, plasma hemostasis – for the 3rd quarter of the year. In manuscript we have found that the main localization area of thrombus formation after abdominal operations are general femoral vien and free femoral vien with the “unstable” floating ultrasound types of thrombi. We set that the best efficacy in the before surgical prophylaxis and in the treatment of venous thromboembolism is shown to the group of direct Xa factors inhibitors and low weight fractioned heparins (LWF-heparins) in contrast with classical use of non-fractioned heparins.