Heat Transfer in Health and Healing1

Abstract

1Our bodies depend on an exquisitely sensitive and refined temperature control system to maintain a state of health and homeostasis. The exceptionally broad range of physical activities that humans engage in and the diverse array of environmental conditions we face require remarkable strategies and mechanisms for regulating internal and external heat transfer processes. On the occasions for which the body suffers trauma, therapeutic temperature modulation is often the approach of choice for reversing injury and inflammation and launching a cascade of healing. The focus of human thermoregulation is maintenance of the body core temperature within a tight range of values, even as internal rates of energy generation may vary over an order of magnitude, environmental convection, and radiation heat loads may undergo large changes in the absence of any significant personal control, surface insulation may be added or removed, all occurring while the body's internal thermostat follows a diurnal circadian cycle that may be altered by illness and anesthetic agents. An advanced level of understanding of the complex physiological function and control of the human body may be combined with skill in heat transfer analysis and design to develop life-saving and injury-healing medical devices. This paper will describe some of the challenges and conquests the author has experienced related to the practice of heat transfer for maintenance of health and enhancement of healing processes.

Sustained cutaneous vasoconstriction during and following cyrotherapy treatment: Role of oxidative stress and Rho kinase

“…However, our prior computer modeling simulations show that the differential monitoring depths for temperature and perfusion do not influence the overall findings (23). This conclusion agrees with other studies of direct or simulated temperature measurements during both cooling and passive rewarming (10, 27, 30). While the sample size was sufficient to detect an effect of Fasudil during cooling and passive rewarming it is possible that the lack of effect of Asrocbic Acid relative to the control site was related to a small sample size.…”

Cryotherapy-Induced Persistent Vasoconstriction After Cutaneous Cooling: Hysteresis Between Skin Temperature and Blood Perfusion

“…5 shows the temperature histories at different depths during an exemplar cryotherapy experiment, indicating that temperature dropped by 10, 4.5, 4, 3.5 C at depths of 5, 15, 17.5 and 20 mm into the tissue while the surface temperature reduced by 16 C. Additionally, the simulation shows that the pattern of change in temperature at more superficial layers of tissue where the perfusion measurements was interrogated closely follows the change in temperature on the surface of the skin. Various reports on intratissue temperature via direct measurement or simulation measurements in literature support this general pattern of change in temperature during cooling and passive rewarming [52][53][54][55][56]. Thus, the differential in monitoring depths of temperature and perfusion within the tissue does not appear to contribute to the hysteresis effect.…”

On‐Demand Printing of Wearable Thermotherapy Pad

“…Thermotherapy provides comfort from injuries or other causes, and the detailed efficacy is summarized in Table S1, Supporting Information. [5][6][7] The global thermotherapy market was valued at $794 million in 2017. However, the typical mass-market heat pads are bulky, heavy and inconvenient to use because they are not custom-designed for individuals.…”

“…When thermotherapy is applied to areas in need of more blood circulation, the body's reaction to pain changes with reduced muscle spasms. Thermotherapy provides comfort from injuries or other causes, and the detailed efficacy is summarized in Table S1, Supporting Information . The global thermotherapy market was valued at $794 million in 2017.…”