Experimental Study On The Effect Of Dermabrasion Surgery Combined With Hydrocolloid Dressing On Deep Partial-thickness Burn Wound In Rats

Objective:To observe the effect of dermabrasion operation combined with hydrocolloid dressing on the wound healing of deep partial-thickness burn in rats and to investigate the mechanism of the effect.Methods:60 SD rats were selected and divided into three groups A,B and C according to random number table method,with 20 rats in each group.The skin burn model of the back of rats was established,and the depth of burn was verified by pathological section after the injury.Model group A was treated without any treatment after burn;In group B,dermabrasion treatment was performed early after burn.In group C,the wound was covered with hydrocolloid dressing after early dermabrasion operation.The dermabrasion area and healing area of the wound were measured on the 3rd,7th and 14 th days after modeling,and the decrustation rate and healing rate of the wound were calculated.Wound tissues were collected at each time point,and HE staining and Masson staining were performed to observe the morphological changes of the tissue.The expression of CD68 and CD34 in wound tissues of each group was detected by immunohistochemical method,and the content of macrophages and microvessel density(MVD)were calculated.Results:1.Wound decrustation rate: On the third day after injury,there was no significant difference in wound decrustation rate of each group.On the 7th and 14 th day after injury,thewound decrustation rate of rats in groups B and C was significantly increased,group C> group B > group A,and there was statistical significance(P < 0.05).2.Wound healing rate: On the third day after injury,there was no significant difference in the wound healing rate of each group.On the 7th and 14 th day after injury,the wound healing rate of rats in groups B and C was significantly increased,group C> group B > group A,and there was statistical significance(P < 0.05).3.Histological observation of the wound: On the third day after injury,the inflammatory reaction of the wound in groups B and C was less than that in group A;On the 7th day after injury,a large number of microvessels were formed in group B and group C,and new epithelium and collagen fibers were orderly arranged.On the 14 th day after injury,inflammatory cells were still infiltrated in group A,collagen arrangement was disordered,and neoepithelial proliferation was not obvious.4.The content of wound macrophages: the content of wound macrophages in each group began to increase on the 3rd day and reached the peak on the 7th day,and the content of wound macrophages in group C was higher than that in group A and B,with statistical significance.On the 14 th day after injury,the content of macrophages decreased in each group,and the difference was not statistically significant.5.Wound microvessel density: the wound microvessel density in each group increased first and then decreased.On the 7th day after injury,the microvessel density in group C was significantly higher than that in the other two groups,and the difference was statistically significant.Conclusion:1.Early dermabrasion treatment and hydrocolloid dressing can improve the wound decrustation rate and wound healing rate of burn wound in rats.2.Compared with dermabrasion treatment alone,dermabrasion combined with hydrocolloid dressing can promote the microangiogenesis and improve the microcirculation of the wound in rats with deep partial-thickness burn.Hydrocolloid dressing can stimulate the formation of macrophages,reduce the inflammatory response,accelerate the formation of collagen and promote the wound healing.