Análise comparativa de controles positivos no processo de cicatrização de feridas cutâneas em ratos

Abstract

Introduction: Healing is a physiological process that involves several complex mechanisms, such as the interaction between cells and inflammatory factors that aim to restore the morphological and physiological characteristics of this injured tissue. Many factors interfere in this process, such as wound hydration and use of substances with healing potential. Furthermore, both in practice and in a situation in the experimental field, it is not yet well established which is the ideal substance to assist in the healing process. Therefore, the objective of this work will be to analyze the effect on the healing of skin wounds in rats with the following positive controls: PVPI, Chlorhexidine, Saline, Hydrogel and Sunflower Oil. Objectives: To compare the effect observed in the treatment with 0.9% saline solution, Sunflower Oil, Hydrogel, Chlorhexidine and aqueous PVPI on the healing of induced skin wounds in rats. Methodology: Experimental, prospective, longitudinal, statistical-comparative study. Thirty-five rats, 5 animals destined for the pilot group and the others were randomly distributed in 5 study groups, with 5 animals each. For this, a surgical wound in the dorsal region of the animals was performed and the substances mentioned were applied daily in each experimental group, every 12 hours. On the 3rd, 7th, 14th and 21st day, macroscopic analysis of the wound was performed and after the last analysis the animals were euthanized and histological tissue processing was performed for microscopic analysis. Negative Control Group (GCN): animals that receive an application of saline solution. Sunflower Oil Group (SOG): animals that receive treatment with Sunflower Oil. Hydrogel Group (HG): animals receiving wound treatment with hydrogel. Chlorhexidine Groupp (CG): animals that were treated with chlorhexidine. Aqueous PVPI group (APG): animals that were treated with aqueous PVPI. Results: In the macroscopic evaluation, there was a decrease in the areas of mean injury over the course of days, in all groups, more pronounced from the 7th to the 14th day. On the 7th day, the OG group presented significantly larger area (mean of 560.6 mm2) when compared alone to the SF group (mean of 302.8 mm2), but the other groups did not differ significantly from each other on this day. On the 14th day, significant variation was also found (p = 0.0093, Kruskal-Wallis test), so that the LC group was statistically superior to the SF group (area means 148.4 mm2 and 66.4 mm2, respectively). There was no significant difference between other groups. In histological analysis, it was observed that the proportions of vascular proliferation did not differ significantly between the groups, with p-value not significant (p = 0.07755). There was a significant association only between the groups and the intensity of mononuclear cells (p = 0.0169) and between the groups and the intensity of collagen fibers (p = 0.0486). As for mononuclear cells, more cases were observed with marked manifestation of mononuclear cells in the HG group and discrete in the SF. There was a significant association only between the groups and the intensity of mononuclear cells (p = 0.0169) and between the groups and the intensity of collagen fibers (p = 0.0486). As for mononuclear cells, more cases were observed with marked manifestation of mononuclear cells in the HG group and discrete in the SF. Conclusion: It was concluded that there was a significant reduction within each group, in relation to the wound diameter, macroscopically more accentuated in the SF group. However, it cannot be concluded that this would be the best group for control due to more discrete collagen proliferation.