269-OR: Thermal Regulation of the Diabetic Foot and Its Impact on Blood Perfusion

Abstract

Diabetic foot ulcers (DFU) cause approximately 100,000 amputations every year in the US. Current preventive methods provide suboptimal prevention as several reports indicated that amputation rates are on the rise or have not decreased. Our group has previously developed temperature regulating insoles (TRI) that maintain plantar temperatures at 28°C, as previous research demonstrated that cooler tissue is resistant to ulceration. Our purpose in this study was to explore whether blood perfusion is affected by the cooling effect, via quantifying tissue oxygen saturation (StO2). Twelve subjects were recruited after providing informed consent. Inclusion criterion included being able to walk w/o assistance and not having active DFU. All subjects wore the instrumented shoes, with TRI only in the right shoe. Subjects completed two bouts of 5-minute walking on treadmill at self-selected speeds. Plantar temperatures and StO2 images were collected before and after treadmill walking with hyperspectral (Kent Imaging, CA) and thermal (FLIR® Systems, Inc, USA) cameras. Results indicated that while temperature regulation was on target in the forefoot and heel areas around 28°C (~4°C reduction compared to control side) the average difference in StO2 was only 3.0% (standard deviation of difference=2.8%, p=0.22). This suggests that cooling of the diabetic foot to prevent DFU does not necessarily lead to impaired blood perfusion. Disclosure A. Ersen: None. R. T. Myers: None. K. M. Raspovic: Consultant; Self; Orthofix Medical Inc. M. Ramos-roman: None. T. Lalli: None. Y. Salem: None. G. B. Hirschman: Board Member; Self; Vivonics Inc., Stock/Shareholder; Self; Vivonics Inc. M. Yavuz: None. Funding National Institutes of Health (R43DK109858, UL1TR001105)