A 3-D virtual human thermoregulatory model to predict whole-body and organ-specific heat-stress responses

Abstract

Objective This study aimed at assessing the risks associated with human exposure to heat-stress conditions by predicting organ- and tissue-level heat-stress responses under different exertional activities, environmental conditions, and clothing. Methods In this study, we developed an anatomically detailed three-dimensional thermoregulatory finite element model of a 50th percentile U.S. male, to predict the spatiotemporal temperature distribution throughout the body. The model accounts for the major heat transfer and thermoregulatory mechanisms, and circadian-rhythm effects. We validated our model by comparing its temperature predictions of various organs (brain, liver, stomach, bladder, and esophagus), and muscles (vastus medialis and triceps brachii) under normal resting conditions (errors between 0.0 and 0.5 °C), and of rectum under different heat-stress conditions (errors between 0.1 and 0.3 °C), with experimental measurements from multiple studies. Results Our simulations showed that the rise in the rectal temperature was primarily driven by the activity level (~ 94%) and, to a much lesser extent, environmental conditions or clothing considered in our study. The peak temperature in the heart, liver, and kidney were consistently higher than in the rectum (by ~ 0.6 °C), and the entire heart and liver recorded higher temperatures than in the rectum, indicating that these organs may be more susceptible to heat injury. Conclusion Our model can help assess the impact of exertional and environmental heat stressors at the organ level and, in the future, evaluate the efficacy of different whole-body or localized cooling strategies in preserving organ integrity.

Use of Thermoregulatory Models to Evaluate Heat Stress in Industrial Environments

“…Mainly due to computational restrictions, early models were designed to address specific environmental conditions (e.g., just hot or cold). However, these models have become increasingly more sophisticated to provide higher resolution details of human physiological responses, enabling the combination of complex models and the environments they may be applied to [9][10][11][12][13].…”

Parametric analysis of an efficient boundary condition to control outlet flow rates in large arterial networks

“…Our findings also establish constraints on the parameters controlling the numerical stability of the simulations. The findings from this work are directly applicable to larger and more complex vascular domains encountered at full-human scale.In recent years, the central goal of computational biomedicine to create a virtual human, also referred to as a human digital twin, has become increasingly tangible [1][2][3][4] . A virtual human is a detailed, digital representation of an individual's biophysical processes 5,6 .…”

“…In recent years, the central goal of computational biomedicine to create a virtual human, also referred to as a human digital twin, has become increasingly tangible [1][2][3][4] . A virtual human is a detailed, digital representation of an individual's biophysical processes 5,6 .…”