Cutaneous Vasodilation and Sweating In Grafted Skin During Heat Stress 6–9 Months and 26–38 Months Post‐Surgery

The aim of this investigation was to identify the consequence of skin grafting on active cutaneous vasodilation and sweating in split thickness grafted skin during indirect whole body heating (WBH). Skin blood flow (SkBF) and sweat rate (SR) were assessed from grafted skin and adjacent healthy control skin in subjects 6–9 months (n=13) and 26–38 months (n=13) post‐surgery during normothermia (NT) and WBH (increased internal temperature ~0.8 °C). SkBF and SR were assessed in areas not exposed to direct heating. Cutaneous vascular conductance (%CVC max ) was calculated from the ratio of SkBF to mean arterial pressure and normalized to maximal responses obtained by local heating at 42 °C following WBH. Cutaneous vasodilation was not observed during WBH in grafted skin 6–9 months post‐surgery (NT=38±7%; WBH=39±6%; P=0.51), whereas slight vasodilation was observed in grafted skin 26–38 months post‐surgery (NT=15±5%; WBH=38±8%; P<0.01). Sweating was significantly lower (P<0.01) 6–9 months post‐surgery (ΔSR=0.01±0.03 mg/cm 2 /min) compared to 26–38 months post‐surgery (ΔSR=0.22±0.08 mg/cm 2 /min). Cutaneous vasodilator and sweating responses in both groups were significantly lower compared to adjacent control skin. Attenuated cutaneous vasodilation and sweating during WBH suggests impairment of key controllers of thermoregulation in grafted skin, thereby diminishing the contribution of this skin to overall temperature control. However, cutaneous vasodilation and sweating in grafted skin may improve over time following surgery. Project funded by NIH GM68865 & GM71092