Variability in split-thickness skin graft depth when using an air-powered dermatome: A paediatric cohort study

•Air dermatomes are not consistent in depth of STSG harvested.•The median depth is close to the dialed depth at 0.007 in.•Only 50% of grafts are within 0.002 in. each side of the dialed depth.•Pre- or intra-operative variables cannot be identified that may improve consistency.•This potentially confounds dressing studies using donor site wounds as the test bed.

AimSplit-thickness skin grafts (STSG) taken using calibrated powered dermatomes are assumed to yield a graft of uniform thickness, though this assumption has never been analysed statistically. This study aims to test that assumption in a paediatric population.MethodSTSGs from a consecutive cohort of paediatric patients were analysed for mean thickness, measured from a central biopsy. All STSGs were taken from the thigh at a dialled thickness of 0.007 in. Data were analysed using non-parametric methods.ResultsThere were 140 STSGs taken from 91 children. The median thickness was 6.94 thousandths of an inch, with a spread of thicknesses about this median (IQR 5.05-9.28). There were no significant differences when results were analysed by surgeon, patient age or gender, swipe number within the case, or the number of previous passes with the same blade.ConclusionSTSG thickness is inconsistent, with a broad spread about a median value. This study provides no data to suggest there are pre-operative predictors of STSG thickness being significantly more or less than that dialled on a powered dermatome.