Aim: To investigate the morphology of the rat diaphragmatic pedicles in the normal state and to evaluate the changes that occur under modelled carboxyperitoneum of different durations. Materials and Methods: The study was conducted on sexually mature rats of the reproductive period, housed in an accredited vivarium. The animals were divided into six groups: intact, control, and four main groups. In the main groups, carboxyperitoneum at standard pressure was modelled for one, three, and five hours. Results: The study of microdissections revealed the destruction of the basal membranes of muscle fibres, which, upon histological examination, appeared as a continuous, heterogeneous, structureless mass. The mass also contained single or grouped preserved pyknotic nuclei and macrophages. The muscle fibres were deformed and fragmented in large areas, and transverse striations were absent. The myofibrils were uncoiled and partially lysed or coagulated, acquiring an intense homogeneous eosinophilic colour. The nuclei in the areas of fibre lysis were absent. The capillaries present in the endomysium were full-blooded, while the arterioles in the perimysium contained plasma or a small number of erythrocytes. Conclusions: The assessment of the intensity of the noted changes in the experimental groups with varying durations of carboxyperitoneum revealed a direct correlation between the observed histological changes and the duration of pneumoperitoneum, with notable implications for the morphology of the right and left crus of diaphragm.
Kritsak et al. (Mon,) studied this question.