168 posters,  5 categories,  442 authors 

ePostersLive® by SciGen® Technologies S.A. All rights reserved.

P.1
A comparison of the accuracy and precision of four non-invasive core temperature thermometers during cold stress and rewarming

Primary tabs

Poster Presenter
Affiliations

Rate

Average: 4.5 (2 votes)

Statistics

1828 reads

A comparison of the accuracy and precision of four non-invasive core temperature thermometers during cold stress and rewarming  
CJ Mullington,  S Malhotra*,  CG Wilkinson,  DA Low†,  PH Strutton  
MSk Lab, Imperial College, London, UK, *Anaesthetics, Imperial College NHS Trust, London, UK, †SES, Liverpool  John Moores University, Liverpool, UK

Background

Accurate and precise measurement of core temperature is essential to correctly recognise hyper- and hypo-thermia in clinical practice.
Definitions of Accuracy and Precision (fig 1):
•Accuracy (mean bias)  = the mean difference between the measured value and the  ‘gold standard’1.
•Precision (95% limits of agreement) = the range of bias which will contain 95% of measurements1.
When compared to validated methodologies (e.g. intestinal temperature) a core temperature thermometer  should have a mean bias of <0.5°C (accuracy) and 95% limits of agreement of ±0.5°C (precision)2.
Previous research has shown that many currently used methodologies do not meet these standards2-5.
 
Aim
 
To compare the accuracy and precision of 4 commonly used non-invasive core temperature thermometers against a “gold standard” (intestinal temperature) during cold stress and rewarming.
 
Methods
 
10 healthy subjects lay supine between a water perfused mattress and blanket.
Subjects were cooled for 45 min and then rewarmed for 75 min.
Core temperature was recorded (with different technologies) from the following locations at 5 min intervals (fig 2):
–small intestine (pill telemetry system)
–sublingual space (liquid crystal display)
–axilla (electronic)
–aural canal (thermocouple)
–tympanic membrane (infrared)
Data are displayed as means (+/- 1 standard deviation)
Data were analysed with Bland-Altman repeated measurement methodology1 and one-way ANOVA.
 
Results
 
The sublingual and the aural thermometers were more accurate than the axillary and tympanic thermometers (p<0.001) (fig 4).
The aural thermometer was more precise than either the sublingual or the axillary thermometers (p<0.01) (fig 4).
 
Discussion
 
The aural thermometer was the only device that met the standards of accuracy and precision.
These findings advocate the use of an aural thermocouple over the other devices in conscious patients during the perioperative period.
Use of multiple devices within a clinical area may lead to incorrect diagnoses of hypo-, hyper-, or normothermia.
 
Acknowledgements
 
We would like to thank the OAA for financial support and the study participants  for giving up their time.
 
References
 
1.Bland JM, Altman DG. Measuring agreement in method comparison studies. Statistical Methods in Medical Research 1999; 8(2):135-60.
2.Cork RC, Vaughan RW, Humphrey LS. Precision and accuracy of intraoperative temperature monitoring. Anesthesia and Analgesia 1983; 62:211-4.
3.Langham GE, Maheshwari A, Contrera K, You J, Mascha E, Sessler DI. Noninvasive temperature monitoring in postanesthesia care units. Anesthesiology 2009; 111(1):90-6.
4.Allegaert K, Casteels K, van Gorp I, Bogaert, G. Tympanic, infrared skin and temporal artery scan thermometers compared with rectal measurement in children: a real-life assessment. Current Therapeutic Research 2014; 76:34-8.
5.Lawson L, Bridges EJ, Ballou I, Eraker R, Greco S, Shively J, Sochulak V. Accuracy and precision of noninvasive temperature measurement in adult intensive care patients. American Journal of Critical Care 2007; 16:485-96.
Enter Poster ID (e.gGoNextPreviousCurrent