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emits. This measurement can be taken thanks to an external temperature probe on
the device which analyses and registers the ambient temperature. Therefore, as soon
as the operator holds the thermometer near the body and activates the infrared
sensor, the measurement is taken instantly by detection of the infrared heat
generated by the arterial blood flow. Body heat can therefore be measured without
any interference from the heat of the surrounding environment.
THE DIFFERENT METHODS OF TEMPERATURE MEASUREMENT
Core temperature
Core temperature is the most precise measurement and involves measuring the
temperature in the pulmonary artery by means of a catheter equipped with a
thermal probe which can read the temperature in situ. The same method is
employed for probes measuring the esophageal temperature. However, such invasive
temperature measurement methods require specific equipment and expertise.
Rectal thermometry
Rectal temperature adjusts slowly in comparison to the evolution of the body’s
internal temperature. It has been demonstrated that rectal temperature remains
raised long after the internal temperature of the patient has started to drop and vice
versa. Furthermore, rectal perforations have been known to occur as a result of this
method and without appropriate sterilization techniques, rectal thermometry can
spread germs often found in feces.
Oral thermometry
Oral temperature is easily influenced by recent ingestion of food or drinks and by
breathing through the mouth. To measure oral temperature, the mouth must remain
closed and the tongue lowered for three to four minutes which is a difficult task for
young children to accomplish.
Axillary (armpit) temperature
Although it may be easy to measure axillary temperature, it has been proven that it
does not provide an accurate measurement of the child’s internal temperature. To
take this type of temperature, the thermometer must be wedged tightly over the
axillary artery. Despite the low sensitivity and relative inaccuracy of axillary
temperature in detecting fever, this method is recommended by The American
Academy of Pediatrics as a screening test for fever in newborns.
Tympanic Thermometry
In order to obtain a precise temperature reading, good command of the
