Optimization of Abdominal Cavity Limitation Method for Prolongation of Peritoneal Dialysis in Experiment

Abstract

Introduction. It is known that there are places in the peritoneum where secretory resorption processes occur hundreds of times more actively, in particular Douglas and subdiaphragmatic space, namely, they bear the main burden in the process of peritoneal dialysis. In the available literature, cases of successful and prolonged course of peritoneal dialysis in patients with exclusion, due to the adhesion process, of large peritoneum area are described. We proposed to use the laparoscopic separation (preservation of the upper floor of the peritoneum) with the help of laparoscopic pexia of the large omentum to the parietal peritoneum at the navel level. The main problem in this case is the formation of hermetic floors of the peritoneum without interconnections, which can be achieved by laparoscopic pexia of the large omentum to the parietal peritoneum at the level of the navel. The aim of the study. To improve experimentally the method of fixing the large omentum to the parietal peritoneum to prolong the procedure of peritoneal dialysis. Materials and methods. An experimental study was conducted on 60 Wistar rats. The main group consisted of 30 rats, for which the separation of the upper and lower floors was performed using the patented laparoscopic cross­сutter and bio welding technology. The comparison group was made of 30 rats, for which the separation of the upper and lower floors was carried out by quilting the large omentum to the parietal peritoneum with a continuous seam using a 4­0 polyglycid ligature. All of the rats had two soft polychlorovinyl drainages in the upper and lower abdominal cavity floors through the individual counterparts on the back. After 14 days, 5.0 ml of 0.9% physiological solution painted with “diamond blue” was injected through the “bottom” drainage to the rats. Through the “upper” drainage, 3.0 ml of 0.9% physiological solution was injected and if, after the aspiration, brilliant green was detected, there was no tightness. Also the strength of the formed scar, both functionally and histologically was assessed. The functional test was to determine and compare the pressure of the fluid that depressurizes the floors. To do this, the colored solution, starting with 5.0 ml, and gradually adding of 0.5 ml with a single control aspiration from the upper floor was added to the lower floor. Also during the study, the time taken for omentopexy, the histologic reparative properties of the peritoneum and the omentum on the 1st, 3rd, 7th and 14th day of the experiment were compared. Results. The average duration of the omentoperitoneal pexia experiment in the main group was 19.0 ± 70.0 min, and in the comparison group ­ 35.0 ± 14.0 min. More prolonged duration of omentopexy in the comparison group was due to the frequent erosion of the delicate tissues of the large cap and parietal peritoneum by the ligation, the need for the application of additional nodular seams in the places where insufficient sealing was applied, whereas there was no such cases in the main group when using the bio welding device. In case of unsatisfactory connection the omentum tissue was moved to 0.5 cm above or below the problem area. For the 1st and 3rd day, the number of leukocytes in the blood of the rats of both groups did not differ, however, on the 7th day in the rats of the comparison group, this value was lower than in the main, and on the 14th day the indices almost equaled, however, it was slightly higher in the main group. Histologic signs: in the rats of the main group, necrotic scrub with active leukocyte infiltration was clearly visualized. In the rats of the comparison group, the minor inflammatory processes, leukocyte infiltration were present. On day 3 after the surgical intervention in the rats of the main group ­ active phagocytosis of the burn scrab, many leukocytes and erythrocytes were seen, there were also seen the signs of proliferation with fibroblasts in the center of the compound, whereas in rats of the comparison group around the ligation ­ leukocytes, moderate number of macrophages, isolated red blood cells were visualized. On the 7th day in the main group, the active proliferation processes were determined, the burn scrab almost disappeared, infiltrative­proliferative strain with a pronounced vascular net, multiple fibroblasts were formed, while in the comparison group, the histological changes were not significant, and only single vessels were formed. On the 14th day in the main group the mature connective tissue elements along with young fibrocytes, elastic fibers and fibroblasts were observed. In the comparison group there were weakly defined areas of the formation of connective tissue around the ligation. Consequently, in the rats of the main group, strong connection of the cap with parietal peritoneum was formed, whereas in rats of the comparison group it was maintained only due to the ligation. Comparison of the tightness in the rats of the main group showed satisfactory results in 48 cases (96.0%), in comparison one ­ in 32 cases (64.0 %). Comparison of the functional capabilities of the connection showed that in the main group the starting point of the depressurization began at 7.0 ml, and 100.0 % of depressurization occurred at 11.5 ml. In the comparison group, the depressurization occurred starting with 6.0 ml and 100.0 % ­ after conducting of 8.5 ml. Conclusions. The use of a bio welding device allows improving the abdominal cavity limitation technique for prolonging the peritoneal dialysis and ensuring the formation of the reliable connection between the cap and parietal peritoneum, which is 74.5 % stronger than the ligature.

Keywords

• omentopexy
• peritoneal conservation
• peritoneal dialysis