Quantitative Analysis of Glabrous Skin Blood Flow and its Role in Human Thermoregulation

Abstract

Glabrous (hairless) skin found on the hands, feet, face, and ears is a unique component of the thermoregulatory system. Its anatomy and control physiology differ markedly from those of the rest of the skin. Glabrous regions contain vascular networks capable of supporting large blood flows due to the presence of highly tortuous and densely packed arteriovenous anastomoses (AVAs) and associated venous collecting networks [1]. When dilated, these vessels bring large volumes of blood close to the body surface where they function as highly efficient heat exchangers. Furthermore, the manner in which this blood flow is controlled is very unique, exhibiting, for example, rapid and high-magnitude responses, as well as a greater sensitivity to central core signals [1]. In this light, glabrous skin is an important but often overlooked tool the body uses to rapidly and finely adjust energy balance to maintain thermal equilibrium.

Novel temperature‐controlled sleep system to improve sleep: a proof‐of‐concept study

“…The glabrous areas of the body, exemplified by the palms of the hands, soles of the feet, surface of the ears, and certain facial sites, play an important role in thermoregulation. They are comprised of a dense vascular network of arteriovenous anastomoses (AVAs) (Hensley et al, 2012) that serve as the primary heat transfer portal when high rates of heat exchange are required. Indeed, the diameter of AVAs can vary 10‐times or more than that of capillaries under full vasodilation (Diller, 2015) to enable perfusion of a very large volume of blood flow, between 25% and 50% of the total cardiac output, to efficiently dissipate body heat and modulate CBT (Hensley et al, 2013; Taylor et al, 2014).…”

50 Years of Computer Simulation of the Human Thermoregulatory System

“…Over subsequent years the Wissler human thermal model has evolved in its physiological, structural, and control complexity and sophistication in representing the highly nonlinear processes by which the core temperature is maintained with small acceptable variations in the face of a remarkably broad range of environmental and internal stressors. The model has been applied to simulate transient thermoregulatory behavior for numerous environmental heat exchange conditions and types and levels of physical activity [2][3][4][5][6][7][8][9][10][11][12]. Alternative approaches have been presented for computer simulation of human thermoregulation, dating from a similarly early period of development [13][14][15] to contemporary efforts [16][17][18].…”