Abstract : Despite the apparent advantages, laparoscopic surgery and carbon dioxide (CO2) affect numerous organs and systems of the body, including the brain, lungs, kidneys, and liver. During laparoscopic surgery, the diaphragm is displaced caudally by 2-3 cm due to the presence of pneumoperitoneum, resulting in a reduction in lung volume. The aime of this study was to investigate the histological changes in the cruses of diaphragm in cases of obstructive jaundice in combination with pneumoperitoneum. In order to achieve the objective of this study, a total of 60 healthy, mature rats, all of which were six months of age, were divided into four separate experimental groups. The induction of obstructive jaundice was modelled by means of ligation of the common bile duct, while pneumoperitoneum was created using an insufflator connected to a carbon dioxide cylinder through a Veresch needle. Histological material was then stained with haematoxylin and eosin. The presence of circulatory disorders in the microcirculatory system and medium-sized vessels was detected under the influence of bilirubin intoxication. Morphological signs of endothelial dysfunction were observed, and small lymphocytic infiltrates were also detected in the endomysium and perimysium. On longitudinal sections, transverse striation was often weakly expressed or not visualised, and there were foci of sarcoplasmic disintegration and fragmentation of the fibres themselves. Under the influence of intra-abdominal pressure, the morphological picture deteriorated. The presence of areas of dystrophic and degenerative changes in muscle fibres, manifesting as sarcoplasmic homogenisation and eosinophilia, was observed. Intermuscular spaces were characterised by increased cellular infiltration. Upon longitudinal sections, fibres of varying diameters exhibited uneven staining and disarrayed myofibrils, while transverse striations were also uneven and poorly expressed. Foci of sarcoplasmic disintegration and fibre fragmentation were identified. Polymorphonuclear cell infiltrates were detected in the endomysium and perimysium, in which lymphocytes and macrophages predominated. Stromal oedema increased, resulting in the loss of compactness of the muscle layer. Based on the histological data obtained, it was stated that obstructive jaundice leads to structural changes in the diaphragm and that the injury caused by pneumoperitoneum depends on the duration of intra-abdominal pressure.