The paper gives the results of a study conducted in 3 groups of neurosurgical patients in the analysis of autoptic material over 15 years in order to detect pulmonary arterial thromboembolism (PATE) as a cause of postoperative death in neurosurgical patients. In the latter, the incidence of PATE was ascertained to be 5.4%, as evidenced by autopsy and the distribution of the onset of a fatal outcome was biphasic. The informative value of determination of the blood level of fibrin D-dimer was analyzed in neurosurgical patients as a screening method for diagnosing prethrombosis. The method has shown to be of high informative value (about 90% sensitivity) and may be used in clinical practice. The effectiveness and safety of the combined procedure of preventing venous thromboembolic events (mechanical method with a subsequent switching over to pharmacological methods on days 3) were evaluated. The method has proven to be effective and safe.