Effect of Platelet-Rich Fibrin on Inflammatory Response in Refractory Wounds
Objective:To investigate the effect of platelet-rich fibrin(PRF)on inflammatory response in refractory wounds.Methods:From September 2020 to December 2022,40 patients with refractory wounds diagnosed in the Department of Burns and Plastic Surgery of the Affiliated Hospital of Chengde Medical Uni-versity were randomly divided into the PRF group and the control group,with 20 cases in each group.After admission,all patients underwent wound debridement and iodine disinfection.The PRF group was treated with PRF on the wound surface,and the dressing was changed every other day.The control group was treated with sterile dressing change.Wound tissue was collected before treatment,on the 7th and 14th day after treatment for HE staining to observe the pathological changes of the wound.Venous blood was drawn to detect the chan-ges of white blood cell(WBC),C-reactive protein(CRP),and procalcitonin(PCT)levels.Immunohisto-chemical staining of CD34 was performed on the wound tissue to observe the vascularization of the wound be-fore and after treatment.Flow cytometry was used to compare the changes of CD4+T cells and CD8+T cells in the blood of patients before and on the 7th day after treatment,as well as the CD4+T/CD8+T ratio.Results:There was no statistically significant difference in gender,age and course of disease before admission between the two groups(P>0.05).HE staining showed that before treatment,there was a large number of inflammato-ry cell infiltration and a small number of vessels in the wounds of both groups.On the 7th day after treatment,the inflammatory cell infiltration in the PRF group was reduced,and new vessels were formed.On the 14th day after treatment,the inflammatory cells in the PRF group were significantly reduced,the epithelium prolif-erated,and new skin appendages appeared.There was no statistically significant difference in WBC,CRP,and PCT levels before treatment(P>0.05).On the 7th and 14th day after treatment,the inflammatory indi-cators all decreased,and the differences between the two groups were statistically significant(P<0.05).On the 7th and 14th day after treatment,the number of CD34 positive cells in the PRF group was more than that in the control group,and the number of new vessels was more.The epithelialization of the wound also ap-peared earlier than that in the control group.There was no statistically significant difference in CD4+T cells,CD8+T cells,and CD4+/CD8+ ratio between the two groups before treatment(P>0.05).On the 7th day after treatment,the CD4+T and CD4+/CD8+ ratio cells in both groups increased,and the CD8+T cells decreased.There were statistically significant differences in CD4+T cells,CD8+T cells,and CD4+/CD8+ ratio between the two groups(P<0.05).Conclusion:PRF can reduce inflammatory response,improve blood circulation and immune function in refractory wounds.