How can a thermistor be used as a biomedical sensor?
Thermistors are used in temperature probes in a variety of situations, the most common being flexible probes passed into the gullet or into the rectum. They are also at the tip of a device known as a Swan-Ganz catheter, which is a flexible tube which can be inserted into a large vein, passed through the right heart and wedged in a lung artery. With this device it is possible to measure not only a central blood temperature but also the amount of blood pumped by the heart each minute. In biomedical devices the thermistor is generally part of a Wheatsone bridge, and its value is measured against a reference.
