3M 370 Benutzerhandbuch

8 

Overview and Operation

English  202052A

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SpotOn

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 Temperature Monitoring System website to ensure you have the most recent version of this document. 

www.spotontemperature.com reorder #202052A

The SpotOn temperature monitoring system uses zero-heat-flux thermometry to accurately measure a person’s core 

temperature as characterized in Figure 3 below. 1) The SpotOn temperature monitoring system gently warms the 

sensor creating an isothermal  zone under the sensor.  2) Once equilibrated to the core temperature, skin-surface 

heat loss to the environment is prevented and a zero-heat-flux condition is established.  3) When the temperature 

sensor reaches equilibrium with the patient’s core temperature, the SpotOn control unit displays an accurate, 

noninvasive measurement of the patient’s core temperature.

The SpotOn control unit displays noninvasive core temperature measurements obtained from the SpotOn 

temperature sensor. The current temperature is displayed numerically, and previous temperature data is displayed 

graphically as a temperature trend graph. When the sensor is plugged into the sensor cable, the control unit reads 

up to the last two hours of stored temperature data and displays the temperature trend graph.  Disconnections of 

the sensor from the sensor cable are indicated by gaps in the temperature trend graph. The current temperature 

measurement can be continuously transmitted to a patient vital signs monitor through the optional SpotOn 

monitor cable using a standard YSI-400 type input.

The SpotOn sensor is constructed of two layers of medical grade foam and a flexible circuit which contains a 

resistive warming circuit, two calibrated thermistors, and nonvolatile memory. The information that generates the 

temperature trend graph is stored on the SpotOn sensor. If the patient is transferred from one location to another, 

the SpotOn sensor is disconnected from the SpotOn sensor cable so the sensor is left in place on the patient. The 

SpotOn sensor may be reconnected to a different SpotOn sensor cable and control unit when the patient arrives at 

the next point of care. Once the SpotOn sensor is reconnected to the SpotOn sensor cable, the system will begin to 

reequilibrate and will regenerate the stored temperature trend graph and display the patient’s current temperature. 

The act of disconnecting and reconnecting the SpotOn sensor from the sensor cable is indicated by a gap in the 

temperature trend graph.