An apparatus for accurately measuring the body temperature of a patient at the tracheal wall of the patient. The apparatus includes a novel handheld temperature readout assembly that is easy to use by the caregiver and one which clearly and accurately displays the temperature of the patient. The handheld temperature readout assembly includes a handheld housing having a viewing window and a light emitting diode temperature display that is carried by the housing and is readily viewable through the viewing window of the handheld housing for displaying the patient temperature. The apparatus also includes a built-in alarm system to alert to high and low body temperatures.
