Infrared Tympanic Thermometry Research Articles

Clinical accuracy of infrared temperature measurement devices: a comparison against non-invasive core-body temperature

During the coronavirus 2019 (COVID-19) pandemic, the implementation of non-contact infrared thermometry (NCIT) became an increasingly popular method of screening body temperature. However, data on the accuracy of these devices and the standardisation of their use are limited. In the current study, the body temperature of non-febrile volunteers was measured using infrared (IR) thermography, IR tympanic thermometry and IR gun thermometry at different facial feature locations and distances and compared with SpotOn core-body temperature. Poor agreement was found between all IR devices and SpotOn measurements (intra-class correlation coefficient <0.8). Bland-Alman analysis showed the narrowest limits of agreement with the IR gun at 3 cm from the forehead (bias = 0.19°C, limits of agreement (LOA): -0.58°C to 0.97°C) and widest with the IR gun at the nose (bias = 1.40°C, LOA: -1.15°C to 3.94°C). Thus, our findings challenge the established use of IR thermometry devices within hospital settings without adequate standard operating procedures to reduce operator error.

Infrared tympanic thermography as a substitute for a probe in the evaluation of ear temperature for post-mortem interval determination: A pilot study

Reported methods which have been used to measure tympanic temperatures on cadavers up to now are quite invasive. They involve the use of a probe which can perforate the tympanic membrane and frequently causes bleeding from the ear. For this reason a non traumatic method for estimating tympanic temperature should be applied. Infrared tympanic thermometry seems to be a plausible option. Reliability of infrared tympanic thermometry (ITT) has been largely assessed on living individuals but only one author up to now has assessed its applicability for post-mortem interval determination. Thus the authors set out to test the difference between ear temperatures taken with a probe vs. ITT, differences between left and right ear and reproducibility of measurements of ITT. The aim of the study was to verify whether ITT could be a plausible option for measuring ear temperature for PMI estimation. Ear temperatures were taken on 25 cadavers (15 males, 10 females). Temperatures were taken alternately by similarly trained personnel by two technical methods (Checktemp 1 thermocouple probe and First Temp Genius infrared thermometer) for a total of 93 measurements. Statistical analysis of the data was performed using SAS statistical software. The range of temperature measured was from 20 to 28 °C, statistical analysis revealed no differences within the two technical methods, both for right and left ear (ITT: 22.33 ± 0.35 vs. probe: 23.08 ± 0.25; P = 0.087). The study shows the ITT method can be considered as a possible alternative to the probe for measuring ear temperative and further studies should be considered.

Infrared tympanic thermometry in comparison with other temperature measurement techniques in febrile children

: To determine whether infrared tympanic thermometry (ITT) measurements more accurately reflect core body temperatures than axillary, forehead, or rectal measurements during fever cycles in children. : Prospective cohort study. : Pediatric and cardiac intensive care units at a tertiary care children's hospital. : Critically ill children <7 yrs of age with indwelling bladder catheters. : Simultaneous temperatures were recorded during both febrile and nonfebrile periods using ITT, indwelling bladder (core), axillary, forehead, and indwelling rectal measurements in 36 children. : Overall ITT measurements were 0.03 +/- 1.43 degrees F less than core temperature measurements. In comparison, rectal, forehead, and axillary measurements averaged 0.62 +/- 1.44, 0.56 +/- 1.81, and 1.25 +/- 1.73 degrees F less than core temperature measurements. ITT measurements had better agreement with core measurements during increasing and decreasing temperature cycles. Receiver operating characteristic analysis performed on increasing and decreasing temperature cycle data revealed that ITT measurements performed well, with an area under the curve of 0.855 (95% confidence interval, 0.797-0.913) in comparison with rectal measurement area under the curve of 0.777 (95% confidence interval, 0.701-0.853), forehead measurement area under the curve of 0.710 (95% confidence interval, 0.715-0.888), and axillary measurement area under the curve of 0.664 (95% confidence interval, 0.579-0.750). : ITT measurements more accurately reflect core temperatures than any other measurement site during febrile and nonfebrile periods in children. ITT measurements are a reproducible and relatively noninvasive substitute for bladder or rectal measurements in febrile children.

Current practice and knowledge of nurses regarding patient temperature measurement

Background: The measurement of patient temperature by nursing staff is a common activity. In recent years this area of practice has been largely under-investigated despite the introduction of new technologies into clinical practice, such as infrared tympanic thermometry (IRTT).Study aim: To investigate current practice in clinical temperature measurement in general, and the use of IRTT in particular by nursing staff.Sample and methods: 139 nursing staff from a general hospital in the UK were surveyed via a self-administered questionnaire.Main findings and conclusions: The group most involved in temperature measurement was characterized as nursing auxiliary grades with the fewest years of experience. IRTT was the most frequently-used method for measuring patient temperatures, with high perceived accuracy, reliability, ease of use and acceptability to patients. A poor level of understanding and training in the use of IRTT was revealed across all clinical grades. Recommendations for future investigations are made.

Effect of the status after ear surgery and ear pathology on the results of infrared tympanic thermometry

Most publications that deal with infrared tympanic thermometry (ITT) have performed a comparison between the established temperature measurements and ITT. However, to date an understanding of the influence of pathological ear findings on ITT test results is incomplete. Therefore, in the present study ITT was performed in healthy adults (n =21), adult patients with monaural central perforation (n =31) or strong scar formations (n =24) of the tympanic membrane and 18 adult patients after monaural canal wall down surgery. Right and left ear and oral temperature were measured three times by one investigator in a room with a constant temperature of 20-22 degrees C. Between every measurement there was a free time interval of 2 min. In healthy adults (36.50 degrees C vs. 36.51 degrees C) patients with monaural central perforation of the tympanic membrane (36.41 degrees C vs. 36.34 degrees C) and with monaural strong scar formations in the tympanic membrane (36.39 degrees C vs. 36.45 degrees C), no significant difference between the right and left ear could be proved. In contrast to this, a significantly higher temperature in the surgically treated ear compared to the healthy side (36.97 degrees C vs. 36.31 degrees C; P <0.001) occurred in patients with a status of after monaural canal wall down surgery. In summary, it could be demonstrated that, in contrast to minor ear surgery, major ear surgery such as canal wall down has a significant influence on the results of ITT. If a patient's history gives reference to previous ear surgery, an otoscopic examination is necessary in order to exclude the presence of an after-canal-wall-down surgery status and thus to avoid false ITT test results.

Comparison Of Tympanic And Rectal Temperatures In Adults At Rest And Exercise

Infrared tympanic thermometry (ITT) has been developed to measure tympanic temperature (Tty). However, ITT has not been extensively evaluated against rectal temperature (Tre). This study measured Tty and Tre in 13 college-aged subjects (5 men and 8 women) at rest and exercise in a thermoneutral environment (22–24°C). Subjects first performed 90-min steady state exercise at 55%VO2peak. This was followed by a 30-min time trial, which required subjects to perform the amount of work equivalent to 30 minutes at 60% of their VO2peak. Although a statistically Significant correlation was observed between Tty and Tre at rest or exercise, the variance in Tty accounted for only 36% of the total variance in Tre and the standard error of estimate was high (+0.48). Moreover, Tre was 0.9°C (P<0.05) higher than Tty at all time points for men and women combined, confirming that Tty and Tre do not agree. Tty was stable during steady state exercise and increased gradually during the time trial for both men and women. However, Tre increased during steady state exercise and then decreased slightly in men, but continued to increase for women during the time trial. These results demonstrate that Tty responses during exercise lag behind Tre responses.FigureIn conclusion, Tty is not a good predictor of Tre in adults at rest or during exercise. Supported by Campbell Soup Company, Inc.

Can training improve the results with infrared tympanic thermometers?

Infrared tympanic thermometry (ITT) is a method for body temperature measurement. Correct measuring technique is said to be important to achieve good results with this method. The objective of this study was to investigate the accuracy and effect of training in the use of infrared tympanic thermometry (ITT) on the measurement results. Nurses trained in the use of ITT, and nurses not trained performed measurement sequences on 65 patients: one rectal and two ITT measurements in each sequence. Mean rectal temperatures were significantly (P < 0.01) higher than with ITT (0.44 +/- 0.42 (SD) degree C for trained, 0.56 +/- 0.4 (SD) degree C for untrained). Coefficient of repeatability for ITT measurements was +/- 0.54 degree C for trained nurses, and +/- 0.48 degree C for untrained. With ITT temperatures adjusted upwards of 0.5 degree C, the sensitivity of ITT for detecting fever as defined by rectal measurements would be 70% for trained, and 54% for untrained nurses. Repeatability and sensitivity for trained and untrained nurses were not significantly (P > 0.05) different. Training had little effect on the accuracy of the measurements. According to our results, ITT is often unreliable and should be used with caution.

Infrared thermometry in the diagnosis and treatment of heat exhaustion.

Infrared (IR) thermometers (FirstTemp 2000A, Intelligent Medical Systems, California) were used to monitor tympanic temperature (Tty) in 12 collapsed fun-runners suspected of suffering exertion-induced heat exhaustion (EIHE). Rectal temperature (Tre) was monitored via digital clinical thermometers. Conditions during the fun-run and in the field treatment centre were cool (air temperature 16-18 degrees C, relative humidity 60-65%). On admission, Tty was (mean +/- SEM) 1.2 +/- 0.3 degrees C lower than Tre. For admission plus subsequent monitoring data pooled, although Tty correlated significantly with Tre (r = 0.86, p < 0.001), mean Tty (37.4 +/- 0.2 degrees C) was significantly lower (p < 0.01) than mean Tre (38.4 +/- 0.4 degrees C). Cotton wool ear pads, applied to 10 of the runners on admission to minimise environmental effects on Tty, did not significantly improve the IR monitoring. A Tty > or = 37.1 degrees C predicted a Tre > or = 38 degrees C (an established diagnostic criterion for EIHE) with a sensitivity of 0.93 and a specificity of 0.63. These data indicate that IR tympanic thermometry, when utilised in cool environments, can result in misdiagnosis of heat exhaustion. Although IR thermometry shows some promise as a rapid, non-invasive means of monitoring core temperature, it should not be used in the diagnosis and treatment of heat exhaustion unless further research validates the method.

Reliability of Infrared Tympanic Thermometry in the Detection of Rectal Fever in Children

See related editorial, "What's Hot and What's Not: The Gold Standard for Thermometry in Emergency Medicine." Study objective: Recently published clinical guidelines for the management of febrile children are based on studies that used rectal temperature data to stratify the risk of bacteremia and septic complications. Appropriate management decisions rely on accurate detection and categorization of fever. Accordingly, this study compared the newer infrared tympanic thermometry (ITT) to rectal thermometry in this regard. Design: Prospective observational study. Setting: Urban teaching hospital ED with annual census of 60,000. Participants: Consecutive children 6 months to 6 years old who had rectal temperatures measured. Interventions: Triage nurses recorded rectal temperatures and bilateral ITT temperatures. Temperatures were correlated by Pearson correlation coefficients and compared using paired t tests with significance set at P<.01. Children were categorized by degree of fever using rectal temperature (afebrile, less than 100.4°F; low fever, 100.4 to 102.9°F; and high fever, more than 102.9°F), and the accuracy of ITT in detecting fever and high fever was determined. Results: Three hundred seventy patients were enrolled in the study. The mean age was 18.4±11.3 months; boys comprised 56% of patients. The mean temperatures were rectal, 101.0±2.0°F; right tympanic membrane, 100.4±1.9°F; and left tympanic membrane, 100.3±1.9°F. The tympanic membrane temperatures were significantly lower than rectal readings ( P<.001 for both right and left versus rectal). Rectal temperatures showed good correlation with both right and left tympanic membrane temperatures ( r =.83 and .85, respectively). ITT was 76% sensitive and 92% specific in detecting fever of 100.4°F or more (positive predictive value, 0.92; negative predictive value, 0.76). In the detection of high fever, ITT was only 57% sensitive but 98% specific (positive predictive value, 0.90; negative predictive value, 0.90). Rectal and TM temperatures differed by at least 0.5°F in 70% of the patients, 1.0°F in 41%, 2.0°F in 12%, and 3.0°F in 3%. Conclusion: Despite the statistical correlation between ITT and rectal temperatures, the modalities may yield significantly different temperatures. The poor sensitivity of ITT in detecting fever and high fever may result in clinically important miscategorizations of individual patients. Current clinical management that is based on the presence and height of fever may be adversely affected if ITT is used. [Brennan DF, Falk JL, Rothrock SG, Kerr RB: Reliability of infrared tympanic thermometry in the detection of rectal fever in children. Ann Emerg Med January 1995;25:21-30.]

Infrared tympanic thermometry in the evaluation of pediatric acute otitis media.

The reliability of infrared tympanic thermometry (ITT) in children and the effect of acute otitis media (AOM) on ITT are unsettled. This study assessed the effect of AOM on ITT and the utility of ITT in the diagnosis of AOM. 520 consecutive children, aged 6 months to 6 years, presenting to the ED of an urban teaching hospital were eligible for this prospective observational study. Nurses recorded oral or rectal reference temperatures (RefTs) and bilateral ITT temperatures upon presentation. Emergency physicians were blinded to the ITT temperatures. AOM was diagnosed according to published clinical criteria. Among 520 patients, 108 had unilateral AOM and 78 had bilateral AOM. In patients with unilateral AOM, the infected ears were warmer (I = 100.4 +/- 1.8 degrees F) than the uninfected ears (U = 100.3 +/- 1.8 degrees F, p = 0.035). However, the disparity in TM temperatures in infected and uninfected ears with unilateral AOM (I - U = 0.2 +/- 0.9 degrees F) was similar to the difference between right and left ears in those without AOM (R - L = 0.1 +/- 0.8 degrees F, p = 0.60). Compared with patients without AOM, patients with AOM demonstrated no significant elevation of ITT temperatures over RefTs (I - RefT = -0.8 +/- 1.2 degrees F in AOM; ITT - RefT = -0.8 +/- 1.2 degrees F in non-AOM; p = 0.94). This study had >99% power to detect a 1.0 degrees F difference for all groups compared. Infrared tympanic temperature are not helpful in diagnosing AOM in children. AOM has little direct effect on ITT temperatures.

The Impact of Technique and Conditions of the Tympanic Membrane Upon Infrared Tympanic Thermometry

The Impact of Technique and Conditions of the Tympanic Membrane Upon Infrared Tympanic Thermometry

The Impact of Technique and Conditions of the Tympanic Membrane Upon Infrared Tympanic Thermometry

The Impact of Technique and Conditions of the Tympanic Membrane Upon Infrared Tympanic Thermometry

Effect of Otitis Media on Infrared Tympanic Thermometry

This study was designed to determine if temperature readings using a new tympanic thermometer are affected by otitis media. These readings were also compared to a rectal or oral temperature. Eighty-four children with unilateral suppurative or non-suppurative otitis media diagnosed clinically by their pediatricians were enrolled in the study. Temperatures were measured in both ears using the Thermoscan PRO-1 Instant Thermometer and rectally or orally by a glass or electronic predictive thermometer. For 67 children with unilateral suppurative otitis media the mean temperature in infected ears was 0.38 degrees Fahrenheit higher than in uninfected ears (p = .005). Neither temperatures measured in affected nor those from unaffected ears differed significantly from oral or rectal control readings. For 17 children with unilateral non-suppurative otitis media there was no statistically significant difference between temperatures in affected and unaffected ears or between the temperatures in either ear and the oral or rectal control. Our data show that temperatures taken in ears with suppurative otitis media are slightly higher than those in normal ears. This difference is of minimal clinical significance and does not affect the accuracy when compared to oral or rectal control readings.

Effect of Otitis Media on Infrared Tympanic Thermometry

Effect of Otitis Media on Infrared Tympanic Thermometry