A study of the calibration for the core body temperature calculation using ear canal temperature measured by thermistor

Most clinically available thermometers accurately report the temperature of whatever tissue is being measured. The difficulty is that no reliably core-temperature-measuring sites are completely noninvasive and easy to use-especially in patients not undergoing general anesthesia. Nonetheless, temperature can be reliably measured in most patients. Body temperature should be measured in patients undergoing general anesthesia exceeding 30 min in duration and in patients undergoing major operations during neuraxial anesthesia. Core body temperature is normally tightly regulated. All general anesthetics produce a profound dose-dependent reduction in the core temperature, triggering cold defenses, including arteriovenous shunt vasoconstriction and shivering. Anesthetic-induced impairment of normal thermoregulatory control, with the resulting core-to-peripheral redistribution of body heat, is the primary cause of hypothermia in most patients. Neuraxial anesthesia also impairs thermoregulatory control, although to a lesser extent than does general anesthesia. Prolonged epidural analgesia is associated with hyperthermia whose cause remains unknown.

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Monitoring of the core body temperature of cows using implantable wireless thermometers

Computers and Electronics in Agriculture ◽

10.1016/j.compag.2019.06.004 ◽

2019 ◽

Vol 163 ◽

pp. 104849 ◽

Cited By ~ 1

Author(s):

Wataru Iwasaki ◽

Shuichi Ishida ◽

Daisuke Kondo ◽

Yuichi Ito ◽

Jun Tateno ◽

...

Keyword(s):

Body Temperature ◽

Core Body Temperature ◽

The Core ◽

Core Body

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Skipping Breakfast for 6 Days Delayed the Circadian Rhythm of the Body Temperature without Altering Clock Gene Expression in Human Leukocytes

Nutrients ◽

10.3390/nu12092797 ◽

2020 ◽

Vol 12 (9) ◽

pp. 2797 ◽

Cited By ~ 1

Author(s):

Hitomi Ogata ◽

Masaki Horie ◽

Momoko Kayaba ◽

Yoshiaki Tanaka ◽

Akira Ando ◽

...

Keyword(s):

Gene Expression ◽

Body Temperature ◽

Clock Gene ◽

Core Body Temperature ◽

The Core ◽

Clock Gene Expression ◽

Meal Timing ◽

Dim Light ◽

Core Body ◽

Skipping Breakfast

Breakfast is often described as “the most important meal of the day” and human studies have revealed that post-prandial responses are dependent on meal timing, but little is known of the effects of meal timing per se on human circadian rhythms. We evaluated the effects of skipping breakfast for 6 days on core body temperature, dim light melatonin onset, heart rate variability, and clock gene expression in 10 healthy young men, with a repeated-measures design. Subjects were provided an isocaloric diet three times daily (3M) or two times daily (2M, i.e., breakfast skipping condition) over 6 days. Compared with the 3M condition, the diurnal rhythm of the core body temperature in the 2M condition was delayed by 42.0 ± 16.2 min (p = 0.038). On the other hand, dim light melatonin onset, heart rate variability, and clock gene expression were not affected in the 2M condition. Skipping breakfast for 6 days caused a phase delay in the core body temperature in healthy young men, even though the sleep–wake cycle remained unchanged. Chronic effects of skipping breakfast on circadian rhythms remain to be studied.

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The Use of Percutaneous Thermal Sensing Microchips for Body Temperature Measurements in Horses Prior to, during and after Treadmill Exercise

Animals ◽

10.3390/ani10122274 ◽

2020 ◽

Vol 10 (12) ◽

pp. 2274

Author(s):

Hyungsuk Kang ◽

Rebeka R. Zsoldos ◽

Solomon M. Woldeyohannes ◽

John B. Gaughan ◽

Albert Sole Guitart

Keyword(s):

Body Temperature ◽

Core Body Temperature ◽

Central Venous ◽

Exertional Heat Illness ◽

The Core ◽

Thermal Sensing ◽

Positive Correlations ◽

The Right ◽

Nuchal Ligament ◽

Core Body

Accurately measuring body temperature in horses will improve the management of horses suffering from or being at risk of developing postrace exertional heat illness. PTSM has the potential for measuring body temperature accurately, safely, rapidly, and noninvasively. This study was undertaken to investigate the relation between the core body temperature and PTSM temperatures prior to, during, and immediately after exercise. The microchips were implanted into the nuchal ligament, the right splenius, gluteal, and pectoral muscles, and these locations were then compared with the central venous temperature, which is considered to be the “gold standard” for assessing core body temperature. The changes in temperature of each implant in the horses were evaluated in each phase (prior to, during, and immediately postexercise) and combining all phases. There were strong positive correlations ranging from 0.82 to 0.94 (p < 0.001) of all the muscle sites with the central venous temperature when combining all the phases. Additionally, during the whole period, PTSM had narrow limits of agreement (LOA) with central venous temperature, which inferred that PTSM is essentially equivalent in measuring horse body temperature. Overall, the pectoral PTSM provided a valid estimation of the core body temperature.

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Heterothermy is associated with reduced fitness in wild rabbits

Biology Letters ◽

10.1098/rsbl.2017.0521 ◽

2017 ◽

Vol 13 (12) ◽

pp. 20170521 ◽

Cited By ~ 7

Author(s):

Shane K. Maloney ◽

Maija K. Marsh ◽

Steven R. McLeod ◽

Andrea Fuller

Keyword(s):

Body Temperature ◽

Oryctolagus Cuniculus ◽

Reproductive Output ◽

Core Body Temperature ◽

The Body ◽

The Core ◽

Temperature Rhythm ◽

Body Temperature Rhythm ◽

Core Body ◽

Growth And Reproduction

An increase in variation in the 24 h pattern of body temperature (heterothermy) in mammals can be induced by energy and water deficits. Since performance traits such as growth and reproduction also are impacted by energy and water balance, we investigated whether the characteristics of the body temperature rhythm provide an indication of the reproductive success of an individual. We show that the amplitude of the daily rhythm of body temperature in wild rabbits ( Oryctolagus cuniculus ) prior to breeding is inversely related to the number of pregnancies in the subsequent seven months, while the minimum daily body temperature is positively correlated to the number of pregnancies. Because reproductive output could be predicted from characteristics of the core body temperature rhythm prior to the breeding season, we propose that the pattern of the 24 h body temperature rhythm could provide an index of animal fitness in a given environment.

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Exercise activates compensatory thermoregulatory reaction in rats: a modeling study

Journal of Applied Physiology ◽

10.1152/japplphysiol.00392.2015 ◽

2015 ◽

Vol 119 (12) ◽

pp. 1400-1410 ◽

Cited By ~ 8

Author(s):

Yeonjoo Yoo ◽

Michelle LaPradd ◽

Hannah Kline ◽

Maria V. Zaretskaia ◽

Abolhassan Behrouzvaziri ◽

...

Keyword(s):

Body Temperature ◽

Heat Generation ◽

Heat Production ◽

Core Body Temperature ◽

Heat Stroke ◽

The Body ◽

Model Parameters ◽

The Core ◽

Treadmill Speed ◽

Core Body

The importance of exercise is increasingly emphasized for maintaining health. However, exercise itself can pose threats to health such as the development of exertional heat shock in warm environments. Therefore, it is important to understand how the thermoregulation system adjusts during exercise and how alterations of this can contribute to heat stroke. To explore this we measured the core body temperature of rats ( Tc) running for 15 min on a treadmill at various speeds in two ambient temperatures ( Ta = 25°C and 32°C). We assimilated the experimental data into a mathematical model that describes temperature changes in two compartments of the body, representing the muscles and the core. In our model the core body generates heat to maintain normal body temperature, and dissipates it into the environment. The muscles produce additional heat during exercise. According to the estimation of model parameters, at Ta = 25°C, the heat generation in the core was progressively reduced with the increase of the treadmill speed to compensate for a progressive increase in heat production by the muscles. This compensation was ineffective at Ta = 32°C, which resulted in an increased rate of heat accumulation with increasing speed, as opposed to the Ta = 25°C case. Interestingly, placing an animal on a treadmill increased heat production in the muscles even when the treadmill speed was zero. Quantitatively, this “ready-to-run” phenomenon accounted for over half of the heat generation in the muscles observed at maximal treadmill speed. We speculate that this anticipatory response utilizes stress-related circuitry.

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Grain feeding increases core body temperature of beef cattle

Animal Production Science ◽

10.1071/an13463 ◽

2014 ◽

Vol 54 (4) ◽

pp. 444 ◽

Cited By ~ 10

Author(s):

R. H. Jacob ◽

V. S. M. Surridge ◽

D. T. Beatty ◽

G. E. Gardner ◽

R. D. Warner

Keyword(s):

Body Temperature ◽

Core Body Temperature ◽

Low Ph ◽

Post Mortem ◽

The Core ◽

Feedlot Steers ◽

Beef Carcasses ◽

Condition Score ◽

Rate Of Cooling ◽

Core Body

The core body temperature and post slaughter loin temperatures of steers fed on grass pasture was compared with those of steers fed a grain-based feedlot diet. The feeding treatments were grass for 300 days (Grass), grass for 150 days then feedlot for 150 days (Short Feedlot) and feedlot for 300 days (Long Feedlot). Temperature telemeters were inserted under the peritoneum of the steers and temperature measured at intervals of 1 h for the 300 days, and then at intervals of 1 min for the 48-h period before slaughter. The pH and temperature decline post mortem was also measured. The carcasses of the feedlot steers were heavier and fatter than those from the Grass-fed steers. The core body temperature of the steers from the feedlot treatments was 0.3–0.4°C higher than for the Grass treatment at the time of slaughter. The loin temperature was higher in the feedlot treatments than the Grass treatment at all times measured post mortem as was the temperature at pH 6. Feedlotting can increase the likelihood of ‘high rigor temperature’ conditions of high temperature and low pH occurring in beef carcasses, due to an increase in core body temperature before slaughter, a decrease in the rate of cooling and an increase in the rate of pH decline post mortem. These effects are possibly due to a combination of a direct effect of feed type on body temperature as well as indirect effects on bodyweight and condition score.

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