VOL: 97, ISSUE: 09, PAGE NO: 43
PHILIP JEVON, RESEARCH NURSE, MANOR HOSPITAL, WALSALL
MELISSA JEVON, SENIOR STAFF NURSE, COMPTON HOSPICE, WOLVERHAMPTON
The tympanic thermometer uses infra-red light to detect thermal radiation (Woodrow, 2000). It is designed for intermittent use, offering a one-off digital reading. It is non-invasive, hygienic, simple to use, comfortable for the patient and quick to register (Bartlett, 1996).
Care should be taken when using the tympanic thermometer, as poor technique can lead to inaccurate temperature measurements. Temperature differences between the opening of the ear canal and the tympanic membrane can be as much as 2.8°C (Hudek et al., 1998). The thermometer probe should be gently placed in the ear canal and allowed to fit snugly. This will prevent ambient air at the opening of the ear canal from entering it, resulting in a false low temperature measurement.
Other causes of false low readings include a dirty or cracked lens, improper technique, incorrect installation of the probe cover and short time intervals (less than 2-3 minutes) between consecutive temperature measurements. Although cerumen (earwax) can lower measurements by 0.3°C (Doezema et al., 1995) it is unlikely that this will affect the management of the patient.
The thermometer should be maintained by the electronics department following the manufacturer’s recommendations.