Body temperature can be measured in a
range of different places, including the axilla,
mouth, ear, forehead and rectum. There is
a wide variety of thermometers available,
including traditional glass, digital, chemical
and infrared. Children under the age of five will
have difficulty keeping a thermometer under
the tongue, and the use of glass thermometers
is no longer recommended because of the risk
of breakage and potential loss of mercury
(Crawford et al 2005). Rectal measurement
should not be done routinely because of the
potential risk of injury (NICE 2013) (Table 1).
Over the past few years, electronic and
infrared thermometers have become common
in clinical practice because of their speed
and accuracy. Non-contact forehead
thermometers are relatively new and measure
heat radiated from the forehead. These are
becoming increasingly popular because of
the non-touch technique, but they may be
unreliable in sick children as poorly perfused
or sweating skin can give a reading up to 1°C
below actual body temperature (Fortuna et al
2010). NICE (2013) has stated that ‘forehead
chemical thermometers are unreliable and
should not be used by healthcare professionals’