The role of aerosolized intraperitoneal heparin and hyaluronic acid in the prevention of postoperative abdominal adhesions

Research progress on animal models of peritoneal adhesion

Peritoneal adhesion is a common complication of abdominal and pelvic surgery that can cause various clinical symptoms, including abdominal pain, intestinal obstruction, and female infertility, significantly impacting patient quality of life. Animal models of peritoneal adhesion are important tools for studying the mechanisms of adhesion formation and evaluating the effectiveness of prevention and treatment. Various methods for constructing animal models of peritoneal adhesion include physical injury, chemical injury, ischemia, infection, foreign body stimulation, and simulated surgery; however, none can fully simulate peritoneal adhesion in patients clinically. Therefore, this review aimed to explore previous methods used to construct peritoneal adhesion animal models and summarize their principles, characteristics, and applications. Similarly, it summarizes macroscopic and microscopic evaluation indicators, such as peritoneal adhesion gross assessment, histological scoring, and molecular markers. On the basis of this, we proposed a new animal model of peritoneal adhesion that simulates the factors contributing to peritoneal adhesion formation in clinical surgery. peritoneal adhesion formation was stable and standardized using our proposed model, providing a foundation for the establishment and application of peritoneal adhesion animal models.

[Influence of unmodified and modified sutures on experimental abdominal adhesive process]

OBJECTIVE

Experimental assessment of the effect of modified and unmodified surgical suture material on abdominal adhesive process.

MATERIAL AND METHODS

The study was performed on male rats of the Wistar subpopulation. There were 5 animals in each group. In all animals, midline abdominal incision was followed by suturing the parietal peritoneum with modified and unmodified suture material. All animals were euthanized with carbon dioxide vapors in 14 days after surgery. Macro- and microscopic assessment of severity of abdominal adhesive process was carried out. Two types of preparation of excised complexes 'peritoneum-suture material-adhesion' were applied for histological examination: paraffin sections and embedding in epoxy resin. Specimens were stained by Van Gieson and with methylene blue solution. Histological specimens were examined using Axio Imager A1 light microscope (Zeiss, Germany).

RESULTS

Polypropylene filaments result extensive adhesions occupying about 75% of the area. Adhesions have a dense structure with signs of vascularization. Modification of suture material with solution of polyhydroxybutyrate/hydroxyvalerate and heparin reduce severity of adhesions. The use of modified suture material was followed by adhesions with more loose structure, no signs of vascularization. Adhesions occupied less than 25% of the area. Histological examination of excised complexes 'peritoneum-suture material-adhesion' revealed accumulation of inflammatory cells around the unmodified suture material, while there were no signs of tissue inflammatory process around the modified sutures.

CONCLUSION

Application of polyhydroxybutyrate/hydroxyvalerate and heparin on the surface of surgical sutures is an effective method for prevention of abdominal adhesions.

The role of oral fluvastatin on postoperative peritoneal adhesion formation in an experimental rat model

BACKGROUND

Postoperative peritoneal adhesions are a momentousness complication after abdominal surgery. Although varied means have been used to prevent and treat adhesions, the effects have not been satisfactory. Fluvastatin, a HMG-CoA reductase inhibitors, exhibits a variety of pharmacological effects. Aim of this study was to evaluate the effect of fluvastatin on postoperative peritoneal adhesion formation.

METHODS

Seventy-five male Wistar rats weighting 220-250g were randomly assigned equally to three groups. Group A was given sham operation without treatment, Group B was the model group in which postoperative peritoneal adhesion model was created without medication, and Group C was given oral fluvastatin treatment after postoperative peritoneal adhesion model created. After laparotomy on day 7, macroscopic and pathological assessment were evaluated, IL-1β and t-PA in plasma were performed to measure, and tissue samples were taken to measure MMP-9 protein.

RESULTS

There were significant differences between the groups on adhesion grade (p < .05), IL-1β content of the plasma and t-PA activity of the adhesions (p < .05). The grading of adhesion demonstrated significant differences between all groups. The levels of the IL-1β content of plasma, t-PA activity and MMP-9 of adhesion showed pivotal changes in Group B compared with Group A and C, while the difference between Group A and C was not statistically significant.

CONCLUSION

Oral fluvastatin application could reduce formation of intra-abdominal adhesion by promoting expression of MMP-9 level, lowering the levels of IL-1β and increasing the activity of t-PA after abdominal surgery.