Major Risk Factors Contributing to Split Thickness Skin Graft Failure

Abstract

A retrospective review was done for each wound (n = 223) in all patients (n = 191) who underwent Split Thickness Skin Graft (STSG) placement in the Wound Division at Georgetown University Hospital from January 2014 to March 2017 in order to determine the factors that significantly affect STSG take. In doing so, these factors that prove to significantly affect STSG take can be used to predict the possibility of graft failure, and, thus, determine if additional measures must be taken in order to improve the success of the skin graft. Patient medical records were examined for patient demographics, comorbidities, wound parameters, wound bed prep, post-operative dressing, 30 day graft outcomes, and 60 day graft outcomes. Statistical analysis was performed to determine the significance of each factor, and further analysis was done to determine the association and risk of the statistically significant factors. Statistical analysis showed a significant association between Negative Pressure Wound Therapy (NPWT) for wound bed dressing after STSG placement and successful STSG outcome compared to use of bolster only for the post-surgical wound (χ<sup>2</sup> = 4.66, p=0.0308). The odds of STSG failure in patients who underwent NPWT were approximately 80% less than those who had bolster dressing used for their post-surgical dressing (OR = 0.203). These results indicate that NPWT after skin graft placement yields a greater success rate for split-thickness skin grafts than conventional bolster dressing. In terms of comorbidities, there was also a significant association between congestive heart failure (CHF) and STSG failure (χ<sup>2</sup> = 4.12, p=0.0422). Patients with CHF were approximately 2.55 times more likely to have their STSG fail (OR = 2.55), indicating that CHF is a good predictor of split-thickness skin graft failure. It was also found that bacterial presence and STSG failure also showed an association (χ<sup>2</sup> = 4.66, p=0.0308), in which patients with bacterial presence on the wound prior to debridement were approximately 2.89 times more likely to have STSG failure (OR = 2.89). Although bacterial presence prior to debridement showed an association with STSG failure, bacterial presence after debridement just prior to STSG placement did not show a significant correlation with STSG failure [n<sub>f</sub> = 52 (73.2%) versus n<sub>s</sub> = 95 (62.5%), (p = 0.1150)]. These results suggest that bacterial presence may also be a good predictor of graft failure, however it is possibly the strain of bacteria, not the presence of bacteria that predominantly affects skin graft take. In order to elucidate the role that bacteria plays in the success of STSG take, further experimental analysis is warranted.