[A prospective study of the effect and mechanism of autologous platelet-rich plasma combined with Meek microskin grafts in repairing the wounds of limbs in severely burned patients].

To observe the effect of autologous platelet-rich plasma (PRP) combined with Meek microskin grafts in repairing the wounds of limbs in severely burned patients, and to explore the mechanism. The prospective controlled research method was used. From September 2016 to January 2020, 16 patients aged 18-69 years, with extensive deep burns, including 9 males and 7 females, who met the selection criteria were admitted to the Department of Burns and Plastic Surgery of the 909th Hospital of the Joint Logistic Support Force of PLA. The bilateral limbs with similar injury in 8 patients were divided into Meek skin grafting+PRP group and Meek skin grafting alone group according to the random number table; in the other 8 patients, the limbs with severer injury were included in Meek skin grafting+PRP group, and the limbs on the other side were included in Meek skin grafting alone group. The wounds of affected limbs in the two groups were treated correspondingly. On post surgery day (PSD) 10, the survival and fusion of Meek microskin grafts were observed and the survival rate and fusion rate were calculated; the histological morphology and the angiogenesis of the basal tissue of Meek microskin graft were observed by hematoxylin-eosin staining and immunohistochemical staining, respectively, with the microvessels being counted. Data were statistically analyzed with paired sample test. On PSD 10, the wounds of affected limbs in Meek skin grafting+PRP group were dry, and most of the transplanted skin grafts were closely adhered to the basal tissue; while a small amount of exudate could be found in the wounds of affected limbs in Meek skin grafting alone group, and a small part of the transplanted microskin grafts fell off or poorly attached to the basal tissue. On PSD 10, the survival rate and the fusion rate of Meek microskin grafts in the wounds of affected limbs in Meek skin grafting+PRP group were (94±3)% and (86±4)%, which were significantly higher than (89±4)% and (79±4)% of Meek skin grafting alone group, respectively (=3.633, 4.229, <0.01). On PSD 10, the basal epidermis was closely connected with dermis of Meek microskin grafts in the wounds of affected limbs in Meek skin grafting+PRP group, with more inflammatory cell infiltration and active microvascular hyperplasia, while the basal epidermis was less closely connected with dermis of Meek microskin grafts in the wounds of affected limbs in Meek skin grafting alone group, with obvious degeneration of collagen fibers under the dermis, less inflammatory cell infiltration, and slightly poor microvascular hyperplasia. On PSD 10, the distribution of microvessels in basal tissue of Meek microskin grafts in the wounds of affected limbs in Meek skin grafting+PRP group were densely clustered, while the distribution of microvessels in Meek skin grafting alone group were scattered, sparse, and dotted. On PSD 10, the number of microvessels in basal tissue of Meek microskin grafts in the wounds of affected limbs in Meek skin grafting+PRP group was 36±6 in each 400-fold visual field, which was significantly more than 29±7 of Meek skin grafting alone group (=2.671, <0.05). Autologous PRP can effectively promote the survival rate and fusion rate of Meek microskin grafts in the wounds of limbs after escharectomy in severely burned patients by promoting angiogenesis at the base of Meek microskin grafts.