Reasoning of rational antibacterial therapy for acute bowel obstruction (experimental study)

Abstract

Introduction. Acute intestinal obstruction (GCN) according to the data of both domestic and foreign literature is on the 3-5 place among acute surgical diseases of the abdominal organs. Many authors note that in the postoperative period a large number of complications develops: suppuration of wounds, failure of anastomoses, peritonitis, pyelonephritis, pneumonia. Aim of the study: To study the degree of accumulation of antibacterial drugs in the intestinal wall above the obstacle on the model of experimental obstructive ileus. Materials and methods. The experiment was conducted on 28 laboratory animals (rats) in which a model of obstructive ileus was formed. The control group consisted of 4 animals that did not have antibacterial therapy. In 8 animals, antibacterial therapy was performed with metronidazole; in 8 – ceftriaxone and 8 – ciprofloxacin. Animals were removed from the experiment after 12, 24, 36, and 48 h. At this time, they performed abdominal bioptates, which were located 1 cm above the obstacle. The first fragment was sent for histological examination, the second for the determination of the amount of antibacterial drug in the intestinal wall by high performance liquid chromatography (HPLC). Results of the study and their discussion. According to the chromatogram, metronidazole was accumulated in the intestinal wall above the obstruction site for 24 hours, reaching a peak after 24 h of experimental obstructive ileus, and subsequently, the metronidazole concentration in the intestinal wall continues to decrease up, and to 36 h on the chromatogram the drug is not determined. The study of the amount of ceftriaxone and ciprofloxacin in the intestinal wall in the model of obstructive ileus showed a similar decrease in the ability of the inflamed wall to cumulate these drugs as ileus progresses. It should be noted that in the wall of the inflamed gut, these drugs were found even after 48 hours in bactericidal concentrations. It is established that after 12 hours the existence of obstructive ileus in animals treated with metronidazole, the intestinal wall was thinned, and its size did not exceeded 0.5 mm. After 24 hours. changes from the previous ones were slight: the wall thickness remained 0.5 mm. Significant microscopic changes occurred after 48 hours. The swelling of the wall increased significantly, which caused it to thicken to 1 mm. The changes corresponded to the phlegmon of the intestinal wall, which was confirmed by leukocyte infiltration in all its layers. After 48 hours in the intestinal wall of animals treated with ciprofloxacin and ceftriaxone, destructive changes were manifested in the same manner as purulent inflammation. Conclusions. As the purulent inflammation progresses in the intestinal wall with obstructive ileus, there is a gradual decrease in its ability to accumulate ceftriaxone and ciprofloxacin. However, these antibacterial drugs were detected in bactericidal concentrations in the intestinal wall after 48 h. The accumulation of metronidazole at obstructive ileus at therapeutic concentration occurs in the unmodified intestinal wall during the first 24 hours and is of short duration, which is confirmed by the results of the experiment.