title: Characterizing human skin blood flow regulation in response to different local skin temperature perturbations.
abstract: Small nerve fibers regulate local skin blood flow in response to local thermal perturbations. Small nerve fiber function is difficult to assess with classical neurophysiological tests. In this study, a vasomotor response model in combination with a heating protocol was developed to quantitatively characterize the control mechanism of small nerve fibers in regulating skin blood flow in response to local thermal perturbation. The skin of healthy subjects' hand dorsum (n=8) was heated to 42°C with an infrared lamp, and then naturally cooled down. The distance between the lamp and the hand was set to three different levels in order to change the irradiation intensity on the skin and implement three different skin temperature rise rates (0.03°C/s, 0.02°C/s and 0.01°C/s). A laser Doppler imager (LDI) and a thermographic video camera recorded the temporal profile of the skin blood flow and the skin temperature, respectively. The relationship between the skin blood flow and the skin temperature was characterized by a vasomotor response model. The model fitted the skin blood flow response well with a variance accounted for (VAF) between 78% and 99%. The model parameters suggested a similar mechanism for the skin blood flow regulation with the thermal perturbations at 0.03°C/s and 0.02°C/s. But there was an accelerated skin vasoconstriction after a slow heating (0.01°C/s) (p-value<0.05). An attenuation of the skin vasodilation was also observed in four out of the seven subjects during the slow heating (0.01°C/s). Our method provides a promising way to quantitatively assess the function of small nerve fibers non-invasively and non-contact.
authors.affiliation: Department of Biomechanical Engineering, Delft University of Technology, Mekelweg 2, 2628CD Delft, The Netherlands. Electronic address: yusang.wu@tudelft.nl.
authors.forename: Y
authors.initials: Y
authors.lastname: Wu
authors.affiliation: Department of Anesthesiology and Pain Medicine, Erasmus MC University Medical Center, P.O. box 2040, 3000CA Rotterdam, The Netherlands. Electronic address: m.nieuwenhoff@erasmusmc.nl.
authors.forename: M D
authors.initials: MD
authors.lastname: Nieuwenhoff
authors.affiliation: Department of Anesthesiology and Pain Medicine, Erasmus MC University Medical Center, P.O. box 2040, 3000CA Rotterdam, The Netherlands. Electronic address: f.huygen@erasmusmc.nl.
authors.forename: F J P M
authors.initials: FJ
authors.lastname: Huygen
authors.affiliation: Department of Biomechanical Engineering, Delft University of Technology, Mekelweg 2, 2628CD Delft, The Netherlands. Electronic address: f.c.t.vanderhelm@tudelft.nl.
authors.forename: F C T
authors.initials: FC
authors.lastname: van der Helm
authors.affiliation: Department of Biomechanical Engineering, Delft University of Technology, Mekelweg 2, 2628CD Delft, The Netherlands; Department of Anesthesiology and Pain Medicine, Erasmus MC University Medical Center, P.O. box 2040, 3000CA Rotterdam, The Netherlands; Department of Information, Medical Technology and Services, Maasstad Hospital, Haastrechtstraat 7D, 3079DC Rotterdam, The Netherlands. Electronic address: s.niehof@erasmusmc.nl.
authors.forename: S
authors.initials: S
authors.lastname: Niehof
authors.affiliation: Department of Biomechanical Engineering, Delft University of Technology, Mekelweg 2, 2628CD Delft, The Netherlands; Department of Biomechanical Engineering, MIRA Institute, University of Twente, Building Zuidhorst, P.O. box 217, 7500AE Enschede, The Netherlands. Electronic address: a.c.schouten@tudelft.nl.
authors.forename: A C
authors.initials: AC
authors.lastname: Schouten
mesh_terms: D000328:Adult; D001783:Blood Flow Velocity; D001808:Blood Vessels / Q000294:innervation*; D001833:Body Temperature Regulation; D005260:Female; D006225:Hand; D006801:Humans; D007259:Infrared Rays; D017078:Laser-Doppler Flowmetry; D008297:Male; D008954:Models, Biological; D009412:Nerve Fibers / Q000502:physiology*; D000069336:Neurovascular Coupling; D055420:Perfusion Imaging / Q000379:methods; D012039:Regional Blood Flow; D012867:Skin / Q000098:blood supply*; D012881:Skin Temperature; D013817:Thermography; D013997:Time Factors; D014666:Vasomotor System / Q000502:physiology; D014741:Video Recording
keywords: Modelling; Skin blood flow; Skin temperature; Small nerve fibers; Thermoregulation