What Makes A Thermometer Medically Graded ?
There are a number of factors that make a device medically graded. It is essential that if a thermometer is to be used in a medical or clinical setting the device must be certified. All medical devices, including thermometers, must comply with several regulations and guidelines. This ensures the device is robust and provides accurate information which enables healthcare professionals to make medical decisions or diagnoses.
In the EU, medical thermometers much have the appropriate CE marking (EU Directive 93/42/EC). This demonstrates that the manufacturer has ensured the device meets EU safety, health and environmental requirements and is an indicator of a product’s compliance with EU legislation. Any digital thermometer that gets put on the market must comply with the ASTM E1965-98(2016) standard stating that a device must be accurate within a tolerance of +/-0.2°C. These are a few regulations that make a thermometer suitable for clinical use.
Types of Thermometer
There are many different types of thermometers and these can be categorised into retail and clinical thermometers.
Retail thermometers are widely available through shops, pharmacies and online retailers. Since the COVID-19 pandemic, there has been a rise in the sale of retail thermometers for use for screening.
However, retail thermometers were not designed to be used to make healthcare diagnosis.
The MHRA has warned against the use of such retail thermometers. This is because they do not offer the same level of accuracy as medically graded thermometers.
Types of Clinical Thermometers
Clinical thermometers can be further sub-divided into contact and non-contact thermometers. Some of the most common types are outlined below.
Tympanic thermometers capture infrared energy emitted from the ear canal and convert this into body temperature. Once positioned in the ear, tympanic thermometers take approximately one minute per reading.
Due to the infection risks involved with contact with the patient, a plastic probe cover must be changed on the tympanic thermometer after each use.
They can be uncomfortable for patients due to their invasive nature, especially when the patient is asleep. Tympanic devices are not suitable for children under 2 years old.
Furthermore, there can be difficulty obtaining accurate core body measurements from tympanic devices as obstacles such as hair or wax are not easily identifiable or removable. And yet, tympanic thermometers are still widely used in hospitals.
Another common method of temperature measurement is the axilla, which takes the patient’s temperature from the armpit. The probe of the thermometer is placed under the arm and held in position for between 1 to 4 minutes depending on the device. This method of temperature measurement is commonly used for children and small babies.
This is another invasive method that can be uncomfortable for some patients. This is true in NICU wards where the baby needs to be undressed regularly to take a reading. Baby’s temperature is of paramount importance to recovery and therefore undressing the baby is not ideal. Studies in preterm babies have shown that with each 1°C drop in temperature there is a 28% increase in mortality rate1.
This method is very time consuming given the length of time to take a reading and therefore not ideal for the busy hospital ward. This method also requires probe covers.
Although this method has been decreasing in its use, some clinicians still recommend its use for newborns or young children as it is seen as the gold-standard for accuracy of core body temperature.
This method is not popular for the obvious discomfort it causes the patient. This method also poses a significant infection risk and should never be used on patients who have a low or weakened immune system.
Non-Contact Infrared Thermometer
Medically graded non-contact infrared thermometers are the future of thermometry. Given that around 80% of infection is spread through contact2, these types of thermometers protect against infection as they don’t touch the patient.
This alleviates the need for the single-use plastic probe covers used by contact thermometers – so non-contacts are better for the environment, but more importantly they save nurse’s time. The TRITEMP™ provides an accurate core body temperature reading in a matter of seconds using the simple TAP & TAKE technique.
Non-contact infrared thermometers such as TRITEMP™ are suitable for all age groups and do not disturb the patient. Therefore, the patient comfort benefits are clear.
Temperature measurement is included as part of vital signs monitoring and is an essential tool in the diagnosis of a wide range of healthcare actions.
Taking readings in seconds, the TRITEMP™ non-contact thermometer is the thermometer of choice in many neonatal wards across the world. TRITEMP™ takes temperature without having to cause discomfort by undressing or moving the baby. No need to touch the baby, ensuring infection spread is minimal.