FEATURES OF THE EFFECT OF PNEUMOPERITONEUM ON THE COSTAL PART OF THE DIAPHRAGM IN THE PRESENCE OF MECHANICAL JAUNDICE

Background. Obstructive jaundice causes various pathophysiological consequences, including local effects on the biliary tree and systemic manifestations. Pneumoperitoneum leads to changes in systemic hemodynamics, pulmonary mechanics, and reduced intra-abdominal blood flow to the microcirculatory organs. Obstructive jaundice caused by ligation of the common bile duct is currently a useful experimental model for detailed study of the effects of bilirubin intoxication on organs and systems of the body as a whole. Aim: To analyze the results of histological examination of diaphragm preparations obtained from animals with simulated mechanical jaundice and under the influence of carbon dioxide insufflation with intra-abdominal pressure of 10 mmHg. Materials and methods. To achieve the set goals, 75 healthy sexually mature rats aged 6 months and weighing 220±25 g were selected. The animals were divided into 5 groups of 15 individuals each. The animals of each group except I were subjected to mechanical jaundice simulation. In groups III-V, along with jaundice, pneumoperitoneum was simulated with carbon dioxide for different times. Intra-abdominal pressure at the level of 15 mmHg in the human body causes similar systemic changes in the rat body at a pressure of 10 mmHg. After the experimental plan was completed, the costal part of the diaphragm was selected for histological examination. Results. The presence of mechanical jaundice for 7 days in animals led to a restructuring of the microscopic picture of the muscle section of the respiratory muscle in the form of edema, the presence of dystrophic and degenerative changes in muscle fibers, the presence of cellular infiltrates mainly in the form of lymphocytes. The addition of pneumoperitoneum formed by carbon dioxide contributed to the appearance of foci of cytolysis, the composition of cellular infiltrates included erythrocytes and plasma cells, edema around the vessels, and the endothelium was exfoliated. The greatest destructive changes were after 3 hours. Conclusion. The presence of mechanical jaundice leads to a restructuring of the muscle tissue of the diaphragm. Pneumoperitoneum leads to more pronounced changes, which depend on the duration of intra-abdominal pressure.