Method for Estimating Core Body Temperature from Heart Rate
Technology available for licensing:
This technology aims to prevent heat injury. Hot environments pose a risk of heat illness to people in occupations where heavy workloads and/or protective clothing is necessary. Excessive heat strain can lead to collapse or even death from heat stroke. Personal physiological monitoring is one means of overcoming the limitations of assessing heat strain using environmental monitoring alone. To this end, several heat strain indices have been suggested that accurately indicate thermal work strain from physiological measures that include both heart rate and core body temperature. While these indices appear to provide reliable indications of thermal-work strain, the requisite measurement of core body temperature (Tcore) in free living humans is a challenge. The traditional thermistor/thermocouple probe-based methods of measuring Tcore (i.e., rectal and esophageal) are impractical. Other methods of measuring Tcore externally (e.g., insulated skin and tympanic membrane temperatures) have proven unreliable. This invention describes a set of mathematical parameters that allow the accurate estimation of core body temperature from heart rate alone. This means that ambulatory assessment of thermal work strain is now possible.
Manufacturers of ambulatory physiological monitoring devices targeted at military, first responder, and the sports and fitness markets may be interested in this technology. Enabling an accurate thermal work strain estimation from this algorithm would be a natural addition to these devices.
U.S. National Guard Civil Support Team (CST) member engaged in a chemical biological training event. The
picture was taken during physiological data collection (Buller et al. 2007). The real time physiology was used by the team's
medical officer to help discern which team members were exceeding safe thermal limits. Ensuring encapsulated personnel
do not overheat is difficult without measuring or estimating internal body temperature.