Namisnak Laura H, Haghayegh Shahab, Khoshnevis Sepideh, Diller Kenneth R
Department of Biomedical Engineering, Cockrell School of Engineering, University of Texas at Austin, Austin, TX 78712.
Department of Biomedical Engineering, Cockrell School of Engineering, University of Texas at Austin, Austin, TX 78712; Department of Biostatics, T.H. Chan School of Public Health, Harvard Medical School, Boston, MA 02138.
J Heat Transfer. 2022 Mar 1;144(3):031203. doi: 10.1115/1.4053195. Epub 2022 Jan 18.
Thermoregulation is a process that is essential to the maintenance of life for all warm-blooded mammalian and avian species. It sustains a constant core body temperature in the face of a wide array of environmental thermal conditions and intensity of physical activities that generate internal heat. A primary component of thermoregulatory function is the movement of heat between the body core and the surface via the circulation of blood. The peripheral vasculature acts as a forced convection heat exchanger between blood and local peripheral tissues throughout the body enabling heat to be convected to the skin surface where is may be transferred to and from the environment via conduction, convection, radiation, and/or evaporation of water as local conditions dictate. Humans have evolved a particular vascular structure in glabrous (hairless) skin that is especially well suited for heat exchange. These vessels are called arteriovenous anastomoses (AVAs) and can vasodilate to large diameters and accommodate high flow rates. We report herein a new technology based on a physiological principle that enables simple and safe access to the thermoregulatory control system to allow manipulation of thermoregulatory function. The technology operates by applying a small amount of heating local to control tissue on the body surface overlying the cerebral spine that upregulates AVA perfusion. Under this action, heat exchangers can be applied to glabrous skin, preferably on the palms and soles, to alter the temperature of elevated blood flow prior to its return to the core. Therapeutic and prophylactic applications are discussed.
体温调节是一个对所有温血哺乳动物和鸟类物种维持生命至关重要的过程。面对各种各样的环境热条件以及产生内热的体力活动强度，它能维持恒定的核心体温。体温调节功能的一个主要组成部分是通过血液循环在身体核心和体表之间进行热量传递。外周血管系统在全身血液与局部外周组织之间充当强制对流热交换器，使热量能够对流到皮肤表面，在局部条件允许的情况下，热量可以通过传导、对流、辐射和/或水的蒸发在皮肤表面与环境之间进行传递。人类在无毛皮肤中进化出了一种特别适合热交换的血管结构。这些血管被称为动静脉吻合支（AVAs），可以扩张到较大直径并容纳高流速。我们在此报告一种基于生理原理的新技术，该技术能够简单、安全地接入体温调节控制系统，从而实现对体温调节功能的操控。该技术通过对覆盖在脊柱上方体表的控制组织进行局部少量加热来运作，这种加热会上调动静脉吻合支灌注。在这种作用下，可以将热交换器应用于无毛皮肤，最好是手掌和脚底，以在血液回流到身体核心之前改变高血流量的温度。文中还讨论了该技术的治疗和预防应用。
