A systematic performance evaluation of brain and body temperature sensors using ultra-stable temperature references

Abstract

The impact of a rise in the temperature of the human brain in patients who have suffered cerebral damage is not completely understood. Current studies are ambiguous; some show that a high brain temperature, and others a low brain temperature, is an indicator of poor prognosis. The reported effect is often very subtle, at the <0.5°C level, and this may be due to the performance, or even the location of the temperature sensor. This study investigates the first of these issues, i.e. the performance of the sensor. Here performance validation is undertaken for three commonly used temperature sensors for brain and body temperature measurement, using ultra-stable temperature references. At body temperature all three sensor types performed within manufacturer's specifications. Given that only a small number of temperature sensors were tested, the indication is that, provided the sensors are located correctly, the small observed differences in temperature are real – though the issue of clinical significance is still to be addressed.

Keywords:

• Brain
• Body
• Temperature
• Fixed-point
• Calibration

Acknowledgements

We thank Mr Timothy Rainey for his expert technical assistance and Mrs Jayne Gray of NPL for performing the calibration of the two fixed-point cells.

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.