Optimization of a sensor head for blood temperature measurement during hemodialysis

In order to control blood temperature during hemodialysis, a precise measurement of blood temperatures in the extracorporeal system is needed. A device was designed to measure the temperature of blood inside a standard PVC tube system for hemodialysis. Because of the high thermal resistance of the tube wall the sensor head surrounding the tube sensor has to be heated up to the measured blood temperature to minimize the influence of environment temperature. Quality parameters to specify the characteristics of sensor heads will be derived. Theoretical considerations will lead to an optimal design of the sensor head for precise measurements and a fast response to blood temperature variations.