There are many studies of single lung ventilation (SLV), which are mostly limited to reducing lung damage by changing ventilation strategies or comparing differences in lung damage caused by different lung isolation devices. There is no study comparing the morphological changes of ventilated lungs using different strategies of artificial lung ventilation. The aim of the study was to examine pathomorphological changes in the ventilated lung during thoracic surgery using SLV. A randomized study was performed on 40 patients who underwent thoracic surgery using SLV. After signing the informed consent, the patients were divided into two groups. In the control group (40 patients) with ventilation “by volume” (VCV), in the study group – ventilation “by pressure” (PCV) with the addition of PEEP 5 mm. During surgery in the thoracic cavity with the help of SLV performed transbronchial biopsy of the parenchyma of the ventilated lung to study the pathomorphological changes after ventilation with different modes. The biopsy was performed using a bronchoscope, which was inserted through the endotracheal tube into the lung, opposite the side of the operation (after the end of SLV and “inclusion” of the collapsed lung). The morphological changes caused by the ventilator were investigated. Pathomorphological examination of the non-collapsed lung (which participated in gas exchange during SLV) was as follows: the control group found significant changes in the alveolar wall with its edema, thickening of the interstitial lung, vascular occlusion, severe inflammatory cell infiltration and damage to alveolar structures. The alveoli collapsed and disappeared. The alveolar structures of the study group were better than the control group: pulmonary interstitial and alveolar exudates, as well as inflammatory cell infiltration were significantly reduced compared to those in the control group. The results of the study suggest that the use of PCV with “moderate” PEEP can significantly improve oxygenation and reduce acute ventilatory injury of the lungs compared to VCV during SLV.

Annotation. One lung ventilation (OLV) is one of the most difficult intraoperative methods of respiratory support for anesthesiologists. OLV should provide the most comfortable surgical field, maintaining proper gas exchange and minimizing damage to both lungs. This anesthetic procedure has a significant inflammatory response, so using perioperative corticosteroid therapy to suppress inflammatory mediators is recommended as an approach to improving prognosis. Therefore, the aim of this study was to determine how the preoperative administration of methylprednisolone affects the systemic proinflammatory response of cytokines during thoracic surgery. The analysis was performed for 80 patients who underwent surgeries in the thoraco-abdominal department of the Shalimov National Institute of Surgery and Transplantology. Patients were divided into 2 groups (study – 40 patients who were administered methylprednisolone 10 mg / kg intravenously during induction of anesthesia and control – 40 patients without methylprednisolone). Before surgery and in the postoperative period on days 1, 3 and 5, the surface phenotype of peripheral blood lymphocytes and the expression of IL-6 by monocytes were determined by flow cytofluorometry. The author's MedStat package was used for statistical analysis (Lyakh Yu.E., Guryanov V.G., 2004–2012). Postoperative indicators of IL-6 monocyte expression in the blood of patients administered methylprednisolone were significantly lower on the 1st and 3rd postoperative day (p<0.001). Thus, preoperative administration of methylprednisolone reduces the release of pro-inflammatory cytokines and improves the condition of patients after thoracic surgery. We consider it expedient to conduct further research on the administration of methylprednisolone for several days in the postoperative period.

For the purpose of single-lung ventilation, various methods of lung isolation are used in the world, which is a prerequisite for many thoracic, cardiac and esophageal surgeries. Numerous studies have reported various methods for determining the optimal suitability between the diameter of the tube and the diameter of the left main bronchus for adequate ventilation and gas exchange during operations on the thoracic cavity. However, there is no consensus among anesthesiologists on the choice of tube size for effective lung ventilation and isolation. We have developed a new mathematical formula for determining the appropriate size of the left bilateral luminal endobronchial tube (LDT). The aim of the study was to determine the effectiveness of the developed standardized mathematical formula for determining the appropriate size of LDT for use in thoracic anesthesiology. The study was performed on 192 patients with diseases of the thoracic cavity (esophagus, lungs, mediastinum), operated on in the thoracoabdominal department of the Shalimov National Institute of Surgery and Tranplantology. A retrospective comparison group – 96 patients after thoracic surgery, which used the choice of LDT size according to the well-known Slinger method “according to the patient’s height”. The study group consisted of 96 patients after thoracic surgery, in which the choice of the size of the bifurcated endobronchial tube was used according to the developed method (according to the formula that evaluates morphometric indicators of height, sex and diameter of the left main bronchus). The application of the proposed method reduces (p = 0.001) the risk of pulmonary complications, HR = 0.39 (95 % CI 0.22-0.70) compared to traditional methods. The risk decreased 2.5 times.

Annotation. Pulmonary complications are a key problem in the postoperative period in patients with diseases of the thoracic cavity. They are characterized as the main factors of longer recovery and hospital mortality. The aim of the study was to compare the indicators of oxygenation of patients and the number of postoperative pulmonary complications after thoracic surgery, depending on the method used to select a dual endobronchial tube. The study was performed on 192 patients with diseases of the thoracic cavity (esophagus, lungs, mediastinum), operated on in the thoracoabdominal department of the Shalimov National Institute of Surgery and Tranplantology. A retrospective comparison group – 96 patients after thoracic surgery, which used the choice of DLT size according to the well-known method of Slinger “according to the patient's height”. The study group consisted of 96 patients after thoracic surgery, in which the choice of the size of the dual endobronchial tube was used according to the developed method (according to the formula that evaluates morphometric indicators of height, sex and diameter of the left main bronchus). EZR v 1.54 statistical software was used for statistical calculations. (graphical user interface for statistical software R version 4.0.3, R Foundation for Statistical Computing, Vienna, Austria). Pulmonary complications developed in 33 (34.4%) patients of the control group and in 13 (13.5%) patients of the study group, the difference was statistically significant, p=0.001. One-factor analysis revealed a link between the risk of complications and the indicators method, sex, PaCO2, PaO2. For the study group, the risk of complications is lower (p=0.001), BP=0.30 (95% CI 0.15-0.61) compared with the control group. The risk of complications for men is higher (p=0.048), BP=2.33 (95% CI 1.01–5.37) compared to women. An increase in the risk of complications with an increase in PaCO2 (p<0.001), BP=1.34 (95% CI 1.21-1.49) with an increase in the indicator by 1 unit, respectively. With increasing PaO2, the risk of complications decreases (p<0.001): BP=0.96 (95% CI 0.94-0.98) – with increasing 1 unit. Thus, the application of the proposed method in comparison with the traditional method reduces (p=0.001) the number of postoperative pulmonary complications by 2.5 times (from 34.4% to 13.5%).

Introduction. Pulmonary complications are one of the most common after surgery on the thoracic cavity. Although the incidence of pulmonary complications is gradually decreasing, recent studies have shown that they still occur in 26% -38% of cases. Pulmonary complications are also a major cause of hospital mortality and may be an independent risk factor for worse long-term survival [1, 2, 3]. The goal of the work. Therefore, the aim of the work was to improve the results of treatment of patients after thoracic surgery by developing an algorithm for anesthesia for perioperative prevention of pulmonary complications. Materials and methods. The study was performed on 192 patients with diseases of the thoracic cavity (esophagus, lungs, mediastinum), underwent surgery in the thoracoabdominal department of the Shalimov’s National Institute of Surgery and Transplantation. Retrospective control group – 96 patients after thoracic surgery, which used conventional methods of perioperative management. The study group – 96 patients after thoracic surgery, which used perioperative anesthesia algorithm for the prevention of pulmonary complications. Statistical software EZR v. 1.54 was used for statistical calculations (graphical user interface for statistical software R version 4.0.3, R Foundation for Statistical Computing, Vienna, Austria). Results and discussion. One-factor analysis revealed a relationship (p = 0.001) of the risk of complications with the method of prevention of pulmonary complications. When conducting a multifactor analysis, it was found that the proposed method of prevention of pulmonary complications can reduce (p = 0.001) the risk of development, HR = 0.27 (95% CI 0.13-0.58) compared with the control group (with standardization by sex, weight, ASA of the patient). Pulmonary complications developed in 33 (34.4%) patients of the control group and in 13 (13.5%) patients of the study group, the difference was statistically significant, p = 0.001. Thus, the use of the proposed technique reduces (p = 0.001) the risk of complications, HR = 0.39 (95% CI 0.22 - 0.70) compared to traditional methods. Conclusions. Thus, the developed algorithm for the prevention of pulmonary complications after thoracic surgery has significantly improved the results of surgical treatment of patients by reducing the number and reducing the risk of these complications by 2.5 times (from 34.4% in patients in the control group to 13.5% in patients in the study group).