Influence of low ambient temperature on epitympanic temperature measurement: a prospective randomized clinical study

Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine

Hermann Brugger²  Georg Rammlmair¹  Bernhard Rainer⁵  Georg Hofer⁴  Norbert Überbacher³  Tomas Dal Cappello²  Giovanni Avancini²  Gabriel Putzer⁶  Emily Procter²  Giacomo Strapazzon² 

[1] Department of Anaesthesiology and Critical Care Medicine, General Hospital of Bressanone, Bressanone, Italy;EURAC Institute of Mountain Emergency Medicine, Bolzano, Italy;Department of Otolaryngology, General Hospital of Bressanone, Bressanone, Italy;Department of Anesthesiology and Critical Care Medicine, General Hospital of Silandro, Silandro, Italy;Department of Anaesthesiology, Marienklinik, Bolzano, Italy;Department of Anaesthesiology and Critical Care Medicine, Innsbruck Medical University, Innsbruck, Austria

关键词: Non-invasive temperature measurement;    Thermistor thermometer;    Core body temperature;    Epitympanic temperature;   

Others  :  1231189
DOI  :  10.1186/s13049-015-0172-5

 received in 2015-04-22, accepted in 2015-10-28,  发布年份 2015

【 摘 要 】

Background

Epitympanic temperature (T _ty ) measured with thermistor probes correlates with core body temperature (T _core ), but the reliability of measurements at low ambient temperature is unknown. The aim of this study was to determine if commercially-available thermistor-based T _tyreflects T _corein low ambient temperature and if T _tyis influenced by insulation of the ear.

Methods

Thirty-one participants (two females) were exposed to room (23.2 ± 0.4 °C) and low (−18.7 ± 1.0 °C) ambient temperature for 10 min using a randomized cross-over design. T _tywas measured using an epitympanic probe (M1024233, GE Healthcare Finland Oy) and oesophageal temperature (T _es ) with an oesophageal probe (M1024229, GE Healthcare Finland Oy) inserted into the lower third of the oesophagus. Ten participants wore ear protectors (Arton 2200, Emil Lux GmbH & Co. KG, Wermelskirchen, Switzerland) to insulate the ear from ambient air.

Results

During exposure to room temperature, mean T _tyincreased from 33.4 ± 1.5 to 34.2 ± 0.8 °C without insulation of the ear and from 35.0 ± 0.8 to 35.5 ± 0.7 °C with insulation. During exposure to low ambient temperature, mean T _tydecreased from 32.4 ± 1.6 to 28.5 ± 2.0 °C without insulation and from 35.6 ± 0.6 to 35.2 ± 0.9 °C with insulation. The difference between T _tyand T _esat low ambient temperature was reduced by 82 % (from 7.2 to 1.3 °C) with insulation of the ear.

Conclusions

Epitympanic temperature measurements are influenced by ambient temperature and deviate from T _esat room and low ambient temperature. Insulating the ear with ear protectors markedly reduced the difference between T _tyand T _esand improved the stability of measurements. The use of models to correct T _tymay be possible, but results should be validated in larger studies.

【 授权许可】

   
2015 Strapazzon et al.

【 图 表 】

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