Exploring the Role of Perfusion in Skin Graft Viability on the Scalp and Lower Limb: An Analysis of Graft Bed, Margin, and Donor Skin Using Laser Speckle

Abstract

Background/Objectives: Reperfusion is a major determinant of skin graft viability. The contributions of the perfusion status of the wound bed, wound margin, and donor skin to the success of the skin graft are unclear. We aimed to evaluate the relationship between perfusion variables and graft necrosis extension on the scalp and lower limb. Methods: A prospective study was conducted on adults undergoing skin graft closure after skin cancer excision on the scalp (n = 22) and lower limb (n = 20). Perfusion was measured intraoperatively and non-invasively with laser speckle contrast imaging on the graft bed, margin, and donor skin. By day 28, graft necrosis extension was quantified. Results: On the scalp and lower limb, graft bed perfusion very strongly correlated with necrosis extension (r = −0.82, p < 0.001 and r = −0.94, p < 0.001, respectively). A significant correlation (r = −0.57, p = 0.01) between margin perfusion and necrosis extension was only observed on the lower limb. The donor skin perfusion and necrosis extension did not correlate in either location (p > 0.05). The graft bed perfusion explained 68% and 89% of the variation in necrosis extension on the scalp and lower limb, respectively. Regression models of necrosis extension based on graft bed perfusion were obtained. For each unit increase in the perfusion of the graft bed, a similar decrease in necrosis extension was observed on the scalp and lower limb (40 and 48 percentage points, respectively). Conclusions: Unlike the perfusion of the wound margin and donor skin, wound bed perfusion plays a significant role in skin graft viability and can predict necrosis extension.