Abstract: Objective To investigate the clinical efficacy of allogeneic platelet rich plasma (PRP) for the treatment of chronic refractory wounds (CRW). Methods A total of 40 patients with CRW who could not be treated with autologous PRP from May 2021 to October 2022 were included. The patients were randomly divided into the treatment group and the control group with 20 cases in each group by using random number table. Patients in both groups underwent debridement after inpatient or outpatient visit. On this basis, patients in the treatment group were treated with allogeneic PRP external application, while patients in the control group were treated with regular wound dressing. The length and width of the wound were measured determine the curative effect. The visual analog scale (VAS) was used to evaluate the pain at the 10th and 20th days after treatment. Results After 10 days of PRP treatment, granulation growth was observed on the wound surface. Granulation tissue grew rapidly in the later stage and the epithelium of the wound margin crawled without obvious inflammatory reaction. After 30 days of treatment, the wound healing rate in the treatment group was 95.9%, which was higher than that in the control group (47.55%) (t=-16.74, P<0.05). The granulation tissue of the wound in the treatment group grew rapidly. The size of the wound was significantly reduced and even healed after treatment (Z=-4.32, P<0.05). The median wound healing time in the treatment group was 34.50 days (31.25, 36.00), which was shorter than that in the control group (50.00 days (45.25, 64.50)) (Z=-5.42, P<0.05). Four cases of wound healing and 16 cases of significant effect were observed in the treatment group, which was significantly better than that in the control group (χ²=40.00, P<0.05). After 10 and 20 days of treatment, the pain of patients in the treatment group was significantly reduced with a statistically significant difference (Z=-5.52, P<0.05). Conclusion For patients affected by restrictive factors such as thrombocytopenia or platelet dysfunction due to age and basic diseases, allogeneic PRP as an auxiliary method can significantly accelerate the healing process of chronic wounds, with good clinical efficacy.

Key words: Refractory wound, Platelet rich plasma, Allogeneic