There have been presented the results of lung cancer cryosurgery simulation using numerical solutions of enthalpy equation according to Godunov method. For the cryodestruction improvement purposes we successfully calculated the effective freezing time taking into account the evolution of an ice ball covering the tumor area. Geometrical transformation parameters of an ice ball have been measured by calculating the temperature distribution and the interface position in biological tissue. Mathematical cryosurgical procedures are described by heat transfer equations in solid and liquid phases. Numerical results for one-dimensional case were verified by comparing with exact solutions. In twodimensional modeling an effective cryotherapy time, which corresponds to freezing time of all tumor parts, was calculated as the area of forming ice balls covering all tumor region. The findings enable to set the effective time of a cryosurgical procedure in lung cancer. The knowledge of temperature distribution and interface position in biological tissue offers an opportunity to a cryosurgeon to finish the procedure within a certain time period to minimize the healthy tissue damage and destroy tumor cells to the maximum. Simulation application enables to schedule cryotherapy in lung cancer more effectively and to a good quality.

Objective. The aim of this paper is to study the pattern of blood coagulation abnormality signs among patients with severe combined craniofacial trauma and their relationship with the trauma outcomes. Materials and methods. A comparative analysis was carried out of the signs of trauma-induced coagulopathy (platelet count, international normalized ratio and activated partial thromboplastin time) on the 1st and 3rd days of hospital stay in two groups of patients with severe combined craniofacial trauma. The first group included 21 patients with a favorable outcome, the second — 37 patients with an unfavorable outcome. Also, a comparative analysis was carried out of the unfavorable outcome frequency among patients, depending on the trauma-induced coagulopathy presence on the 1st and 3rd days of hospital stay. Results. The analysis revealed the presence of statistically significant differences in the mean values of activated partial thromboplastin time on the 1st and 3rd days of hospital stay and of international normalized ratio on the 3rd day of hospital stay among patients with favorable and unfavorable outcomes (p<0.05). Differences in the platelets count on the 1st and 3rd days of hospital stay were not statistically significant (p>0.05). The proportion of patients with signs of trauma-induced coagulopathy on the 1st day was 63.8% (37 patients). On the 3rd day, their proportion increased up to 84.5% (49 patients). The frequency difference of the unfavorable outcomes among patients with signs of trauma-induced coagulopathy and those with blood coagulation signs within the physiological norm on the 1st and 3rd days of hospital stay was not statistically significant. Conclusion. Trauma-induced coagulopathy often occurs in patients with severe combined craniofacial trauma in its acute period, which must be taken into account when performing surgical interventions and intensive care for the patients. According to the study results, it is not possible to confirm the significant impact of this pathology on the outcomes of severe combined craniofacial trauma.

Objective. The purpose of this work is to optimize the surgical approach, in the treatment of patients with craniofacial trauma by using an anatomical and physiological trauma scoring method. Materials and methods. This paper presents an analysis of the main examination and treatment results of 160 patients with craniofacial trauma who were admitted to the first neurosurgical department for treating patients with combined cranio-facial trauma and injuries of the hearing and vision organs of the city hospital named after Alexander N. in St. Petersburg in the period from 2015 to 2019. Results. The surgical approach based on using the trauma anatomical and physiological scoring methods leads to a reduction of the trauma complications and hospital time treatment, including the intensive care unit (ICU) treatment period. Conclusions. The trauma scoring method shown in this paper (including its anatomical and physiological varieties) is an effective tool in determining the surgical tactic. The significance of this method is especially manifested when treating patients with severe injuries.

The authors described the variants of initial surgical d-bridement on the basis of experience of treatment of 183 patients of multistaged treatment program.

Objective. The purpose of this study is to search for the main physiological syndrome complexes that characterize the physical status of patients with combined midface trauma, and to study their clinical significance for assessing the severity of patients’ physical status during their hospital stay. Materials and methods. The study was conducted at the Intensive Care Unit No. 2, as well as at the first neurosurgical department (for patients with combined craniofacial trauma and damage to the hearing and vision organs) of the Alexander Hospital in St. Petersburg in the period from 2016 to 2020. The study included 95 patients with combined midface trauma. 22 physiological parameters that fully characterize the severity of patients’ physical status were measured. The measurement was carried out on the first, third, seventh and fourteenth days of patients’ hospital stays. For patients with an unfavorable outcome data were also collected on the last day of their hospital stays in a retrospective manner. A comparative analysis of the physiological parameters in patients with favorable and unfavorable outcomes was performed, based on the dynamics of the principal component. Results. A statistically significant differences were determined in the average values of the coefficients of the first main component (factor) which was formed basing on data collected on the last day of hospital stay for patients with an unfavorable outcome (the main contributions to which were made by the leukocyte index of intoxication, neutrophil-lymphocyte ratio, absolute numbers of lymphocytes and monocytes) among patients with favorable and unfavorable outcomes on the 1st, 3rd, 7th and 14th days after injury. Conclusions. The analysis carried out showed that the variables leukocyte index of intoxication, neutrophil-lymphocyte ratio, absolute numbers of lymphocytes and monocytes can be used to assess the severity of patients’ physical status and best characterize the physical status of patients with unfavorable outcomes at the last day of their hospital stay. The extrapolation of the revealed combinations of variables has the greatest influence on the division of the group of patients with favorable and unfavorable outcomes on the third day after injury.