Continuous Body Temperature Monitoring Research Articles

Continuous monitoring of body temperature for objective detection of health and safety risks in construction sites: An analysis of the accuracy and comfort of off-the-shelf wearable sensors

Recent studies have shown the potential of wearable sensors for objective detection of health and safety risks in construction workers through their collected physiological data. Body temperature, as the focus of the current study, is one of the most important physiological parameters that can help to detect various health and safety risks such as heat stress, physical fatigue, and infectious diseases. This study aims to assess the applicability and performance of off-the-shelf wearable sensor devices to monitor workers’ body temperature in construction sites by evaluating the accuracy of temperature measurements as well as the comfort of the devices.A total of nine off-the-shelf wearable sensor devices available on the market were initially trialed in the laboratory, and three devices were shortlisted considering a set of selection criteria for further assessment. Over three weeks, the shortlisted wearable sensors were tested on 26 workers in two large construction sites in Australia. The reliability/validity of the selected wearable sensors in measuring body temperature was investigated using Bland-Altman analysis. Human factors were also investigated in terms of the comfort of the devices, their impact on workers’ performance, and the acceptability of being worn for an extended period (i.e., 8 h or more). It was found that all selected devices measured body temperature with a bias of less than one indicating a slight difference in measurements compared to the reference hospital-grade thermometers. Two devices out of the three were also comfortable. The achieved results indicate that it is feasible to develop a continuous temperature monitoring platform using off-the-shelf wearable sensors to detect a range of significant health and safety risks in construction sites objectively. Considering the rapid advancements in manufacturing wearable sensors, future research can adopt a similar approach to include the newly introduced off-the-shelf temperature sensors and select the most appropriate device.

Design of Medical Devices to Monitor Body Temperature, Heart Rate And Oxygen Saturation Levels In Human Body Based On IoT

Understanding body temperature and heart rate plays a crucial role in detecting disease symptoms. Heart rate serves as a vital parameter reflecting human body function, with a typical range of 60-100 beats per minute for adults. This study aims to leverage Internet of Things (IoT) technology to create a monitoring system for heart rate and body temperature.The main objective of this final project is to design a device capable of monitoring body temperature, heart rate, and oxygen saturation levels in the human body. The anticipated benefits of this research include facilitating the continuous monitoring of body temperature, heart rate, and oxygen saturation levels, thus aiding in timely health assessments. To achieve this, the study employs the MLX90614 sensor for temperature measurement and the MAX30100 sensor for heart rate and oxygen saturation level readings. These sensors are integrated with the Arduino Nano microcontroller and NodeMCU ESP8266.The study's findings demonstrate that the sensors effectively measure body temperature, heart rate, and oxygen saturation levels, as confirmed by comparison with medical-grade devices. The system developed in this research performs well and is ready for practical application, providing the desired benefits of enhanced monitoring capabilities for healthcare purposes.

Highly Sensitive Temperature Detection Based on a Frost- and Dehydration-Resistive Ion-Doped Hydrogel-MXene Composite.

Wearable temperature sensors with high sensitivity and stability hold great potential for human health monitoring. However, hydrogels, which are commonly used for wearable devices, often show poor thermal and electrical conductivity and are susceptible to dehydration and freezing. Herein, we developed a frost- and dehydration-resistive temperature sensor based on Fe2+/Ti2CTx/κ-carrageenan (CA)-polyacrylamide (PAM) hydrogel. The Fe2+ ions within the hydrogel existed in two forms: as free ions and bonded ions. The free Fe2+ ions could complex with water molecules, resulting in the improved resistance to dehydration and freezing, as well as enhanced ionic conductivity in the hydrogel. On the other hand, the remaining Fe2+ ions acted as linkers to form coordination bonds with the sulfate groups of CA chains, resulting in the greatly enhanced mechanical strength of the hydrogel. In addition, the Ti2CTx nanosheet-based fillers formed a well-defined porous laminar structure, which reduced the phonon scattering and improved the phonon adsorption within the hydrogel. The Fe2+/Ti2CTx/CA-PAM hydrogel sensor exhibited excellent temperature sensing performance including a good linearity (R2 = 0.998) within a broad working range (-10 to 60 °C), high resolution (0.1 °C), and good repeatability. Furthermore, the sensor was integrated into a wireless system for continuous monitoring of body temperature, demonstrating its potential in healthcare monitoring, electronic skins, and intelligent robots.

Thermogenic Phenotyping in Mice.

Thermogenesis mediated by brown adipose tissue (BAT) and brown-like fat plays an important role in regulating metabolic homeostasis in mammals. Accurate measurement of metabolic responses to brown fat activation, including heat generation and increased energy expenditure is essential for characterizing thermogenic phenotypes in preclinical studies. Here, we describe two methods for assessing thermogenic phenotypes in mice under non-basal states. First, we describe a protocol for measuring body temperature in cold-treated mice using implantable temperature transponders, which allow for continuous monitoring of body temperature. Second, we describe a method for using indirect calorimetry to measure β3-adrenergic agonist-stimulated changes in oxygen consumption, a proxy for thermogenic fat activation.

The pathogenicity comparison of Lagovirus europaeus GI.1 and GI.2 strains in China by using relative quantitative assay

Lagovirus europaeus GI.1 belongs to Lagovirus in the Caliciviridae family. GI.1 causes an acute, septic, and highly lethal disease in rabbits. Lagovirus europaeus GI.2, a new variant of GI.1, has caused explosive mortality in rabbits of all ages in Sichuan Province, China. To explore the differences in pathogenicity of rabbits infected with GI.1/GI.2, we investigated the virulence and disease progression of a naturally occurring GI.1/GI.2 in 4-week-old, 13-week-old, and 25-week-old New Zealand White laboratory rabbits after GI.1/GI.2 infection. Objective measures of disease progression were recorded using continuous body-temperature monitoring. We observed the kittens were infected with GI.2 during the most urgent course of the disease, and GI.1 was not lethal to kittens. We found that the target organ of both GI.1 and GI.2 was the liver, but the disease course of the two viruses was differed. Our study enriches the research on the pathogenicity of GI.1 and GI.2 under the same conditions.

Guest Editorial Special Issue on Sensors for Body Temperature Measurement and Monitoring in a Time of Pandemic

Covid-19 has demonstrated how vulnerable our society remains when it comes to managing a pandemic. There is an urgent need to develop and evaluate new technologies, materials, and methods for rapid measurement and continuous monitoring of body temperature, and accurate detection of elevated body temperature as a symptom of conditions which may lead to a pandemic.

Monitoring Temperature in Children Under General Anesthesia: Nasopharynx Versus Carotid Artery Surface

Continuous body temperature monitoring during anesthesia in children is very important. Hypothermia in children may lead to higher morbidity and mortality. Measurement points to detect the temperature of core body are not simply accessible. In this study we measured the skin temperature over the carotid artery and compared it with the nasopharynx. Totally, 84 children of 2-10 years undergoing elective surgery were selected. Temperature over the carotid artery and nasopharynx was measured during anesthesia. Mean temperature of these points was compared which each other, and the effects of age, sex, and weight change of temperature during anesthesia were evaluated. The mean age of patients was 5.4±2.6 years s. 37% of patients were female, and 63% were male. The mean weight was 20±7 kg. The mean duration of surgery was 60.45±6.65 min. The temperature of the skin and nasopharynx was decreased during surgery as after 60 min, the deference between skin over the carotid artery and the nasopharyngeal area was 1° C. The bodyweight has a significant effect on carotid skin temperature in regression model. Skin temperature over the carotid artery, with a simple correction factor of+1° C, provides a viable noninvasive estimate of nasopharyngeal temperature in children during elective surgery with a general anesthetic.

Ultrahigh Sensitive Au-Doped Silicon Nanomembrane Based Wearable Sensor Arrays for Continuous Skin Temperature Monitoring with High Precision.

Monitoring the body temperature with high accuracy provides a fast, facile, yet powerful route about the human body in a wide range of health information standards. Here, the first ever ultrasensitive and stretchable gold-doped silicon nanomembrane (Au-doped SiNM) epidermal temperature sensor array is introduced. The ultrasensitivity is achieved by shifting freeze-out region to intrinsic region in carrier density and modulation of fermi energy level of p-type SiNM through the development of a novel gold-doping strategy. The Au-doped SiNM is readily transferred onto an ultrathin polymer layer with a well-designed serpentine mesh structure, capable of being utilized as an epidermal temperature sensor array. Measurements in vivo and in vitro show temperature coefficient of resistance as high as -37270.72 ppm °C-1 ,22times higher than existing metal-based temperature sensors with similar structures, and one of the highest thermal sensitivity among the inorganic material based temperature sensors. Applications in the continuous monitoring of body temperature and respiration rate during exercising are demonstrated with a successful capture of information. This work lays a foundation for monitoring body temperature, potentially useful for precision diagnosis (e.g., continuous monitoring body temperature in coronavirus disease 2019 cases) and management of disease relevance to body temperature in healthcare.

Age and Infectious Dose Significantly Affect Disease Progression after RHDV2 Infection in Naïve Domestic Rabbits.

Rabbit haemorrhagic disease virus 2 (RHDV2 or GI.2, referring to any virus with lagovirus GI.2 structural genes) is a recently emerged calicivirus that causes generalised hepatic necrosis and disseminated intravascular coagulation leading to death in susceptible lagomorphs (rabbits and hares). Previous studies investigating the virulence of RHDV2 have reported conflicting results, with case fatality rates ranging from 0% to 100% even within a single study. Lagoviruses are of particular importance in Australia and New Zealand where they are used as biocontrol agents to manage wild rabbit populations, which threaten over 300 native species and result in economic impacts in excess of $200 million AUD annually to Australian agricultural industries. It is critically important that any pest control method is both highly effective (i.e., virulent, in the context of viral biocontrols) and has minimal animal welfare impacts. To determine whether RHDV2 might be a suitable candidate biocontrol agent, we investigated the virulence and disease progression of a naturally occurring Australian recombinant RHDV2 in both 5-week-old and 11-week-old New Zealand White laboratory rabbits after either high or low dose oral infection. Objective measures of disease progression were recorded through continuous body temperature monitoring collars, continuous activity monitors, and twice daily observations. We observed a 100% case fatality rate in both infected kittens and adult rabbits after either high dose or low dose infection. Clinical signs of disease, such as pyrexia, weight loss, and reduced activity, were evident in the late stages of infection. Clinical disease, i.e., welfare impacts, were limited to the period after the onset of pyrexia, lasting on average 12 h and increasing in severity as disease progressed. These findings confirm the high virulence of this RHDV2 variant in naïve rabbits. While age and infectious dose significantly affected disease progression, the case fatality rate was consistently 100% under all conditions tested.

Inkjet-Printed CNT/PEDOT:PSS Temperature Sensor on a Textile Substrate for Wearable Intelligent Systems

The presented work focused on the development of temperature sensors based on specially formulated carbon nanotube (CNT) and poly(3,4-ethylene dioxythiophene): poly(styrenesulfonate) (PEDOT:PSS) based inks which are deposited directly onto the adhesive polyamide-based taffeta fabric with low-cost office-type inkjet printer. Stable and uniform dispersions of CNT and PEDOT:PSS with Triton X-100 were formulated to be used as temperature sensitive inkjet inks. Three kinds of temperature sensors were fabricated using sensitive materials including CNT ink, PEDOT:PSS ink, and CNT/PEDOT:PSS composite ink. Developed sensors are connected to the measuring devices via silver yarns and silver adhesive paste. Sensors are covered with translucent polyurethane welding tape for packaging and protection. All the sensors exhibit negative temperature coefficient (NTC) behavior and sensitivity of 0.15 %/°C for CNT, 0.41 %/°C for PEDOT:PSS, and 0.31 %/°C for CNT/PEDOT:PSS for temperatures varying from room temperature to 50 °C. CNT/PEDOT:PSS composite ink printed sensor achieved better sensing repeatability and demonstrated higher bending stability with a resistance change of 0.3 % up to 1000 cycles than CNT printed and PEDOT:PSS printed sensors. The softness, lightness, and capability to work on flexible or curved surfaces make the developed CNT/PEDOT:PSS composite ink printed sensor a robust candidate for wearable temperature sensor applications, especially in situations requiring continuous body temperature monitoring while satisfying comfort of the user.

Evaluation of a wearable wireless device with artificial intelligence, iThermonitor WT705, for continuous temperature monitoring for patients in surgical wards: a prospective comparative study

ObjectivesTo evaluate a new-generation, non-invasive, wireless axillary thermometer with artificial intelligence, iThermonitor (WT705, Raiing Medical, Beijing, China), and to ascertain its feasibility for perioperative continuous body temperature monitoring in surgical...

Continuous Body Temperature Monitoring to Improve the Diagnosis of Female Infertility.

Introduction Ovulatory dysfunction is a major cause of female infertility. We evaluated the use of continuous body temperature monitoring with a vaginal biosensor to improve standard diagnostic procedures for determining ovulatory dysfunction. Material and Methods This prospective interventional study was performed in a reproductive medicine department of a university hospital. The menstrual cycles of 51 women with infertility were monitored and analysed using three different strategies: sonographic and hormonal assessment (standard approach), continuous core body temperature measurement and analysis using the algorithm of OvulaRing, and lowest daily body temperature measurement monitored with a vaginal biosensor and analysed based on the body temperature curves used in natural family planning. Results Statistically significant differences were found in the temperature curves of women with luteal phase deficiency and polycystic ovary syndrome compared to women with normal menstrual cycles. The analysis of individual cyclofertilograms can be used to detect cycle phases and estimate the date of ovulation. Conclusions Continuous body temperature monitoring with a vaginal biosensor can improve the standard diagnostic procedures used to determine ovulatory dysfunction, especially if dysfunction is due to luteal phase deficiency and polycystic ovary syndrome. Analysis of the lowest daily body temperature combined with the basal body temperature measurements used in fertility awareness methods may be equieffective to continuous body temperature measurements with OvulaRing. The results of this study show that a revised diagnostic approach using fewer hormonal assessments combined with continuous body temperature monitoring can reduce the number of appointments in an infertility clinic as well as the costs.

Sputtered Thermoelectric Nanoparticles for an Ultra-Thin, Flexible and Cuttable Self-Powered Temperature Sensor

Inadequate energy for the growing population has been a major concern in the recent years. Though efforts are being made to alleviate this problem, the crisis still exists. For this reason, the focus of the scientific community is directed towards self-powered technology. As technology is getting smart, smart sensors are also gaining attention. Human beings are getting more and more concerned about their health and opt for the best personalized health care devices. Body temperature is a vital sign which reflects the health condition and thermoregulation in human beings. For continuous monitoring of body temperature, devices which are compact, lightweight and self-powered is therefore desirable. So, we design a highly flexible, ultra-thin and conformable temperature sensor which just uses heat from the body as a power source and senses the body temperature precisely. The sensor works on thermoelectric effect and can detect any surface temperature from room temperature to 100 ˚C and also room temperature to 0 ˚C owing to its conformable and compact design and can be cut into desirable shapes and size. For a temperature gradient of 75 ˚C the sensor gives and output voltage of 0.4 mV and can even detect a human finger touch with an accurate body temperature. Such flexible and thin device can be used in day to day monitoring of human beings enabling it to be used as a wearable temperature sensor, hot or cold surface temperature measurement which may create injury if touched or as a biomedical device for the measurement of hyperthermia or even monitoring the health of pets.

Sputtered Thermoelectric Nanoparticles for an Ultra-Thin, Flexible and Cuttable Self-Powered Temperature Sensor

Inadequate energy for the growing population has been a major concern in the recent years. Though efforts are being made to alleviate this problem, the crisis still exists. For this reason, the focus of the scientific community is directed towards self-powered technology. As technology is getting smart, smart sensors are also gaining attention. Human beings are getting more and more concerned about their health and opt for the best personalized health care devices. Body temperature is a vital sign which reflects the health condition and thermoregulation in human beings. For continuous monitoring of body temperature, devices which are compact, lightweight and self-powered is therefore desirable. So, we design a highly flexible, ultra-thin and conformable temperature sensor which just uses heat from the body as a power source and senses the body temperature precisely. The sensor works on thermoelectric effect and can detect any surface temperature from room temperature to 100 ˚C and also room temperature to 0 ˚C. For a temperature gradient of 75 ˚C the sensor gives and output voltage of 0.4 mV and can even detect a human finger touch with an accurate body temperature. Such flexible and thin device can be used in day to day monitoring of human beings enabling it to be used as a wearable temperature sensor, hot or cold surface temperature measurement which may create injury if touched or as a biomedical device for the measurement of hyperthermia or even monitoring the health of pets.

Mice Do Not Have a Thermoneutral 'Zone': Revising the Definition of Thermoneutrality

The thermal physiology of humans and mice is radically different due to their 3000-fold difference in body size. In a cool environment, mice expend energy to maintain body temperature, while this is limited in adult humans. Here we map the mouse thermoneutral zone (TNZ) using indirect calorimetry with continuous body temperature monitoring. Unexpectedly, we found no range of environmental temperatures over which both metabolic rate and body temperature were constant. Rather, body temperature increased when the ambient temperature was warm enough that cold-induced thermogenesis was no longer required. This result was reproduced in male, female, C57BL/6J, 129, chow-fed, diet-induced obese, and ob/ob mice as well as Trpv1-/-;Trpm8-/-;Trpa1-/- mice with thermal sensory channel deletions. We propose a new upper limit of the TNZ in mice, the point at which body temperature increases, and a new general definition of the TNZ. Thus, the mouse TNZ is not the “zone” of textbooks, but rather a thermoneutral point of 29 °C in the light phase. These observations suggest changes for how mice are used to model human energy physiology and drug development.

Warming the premature infant in the delivery room: Quantification of the risk of hyperthermia

AimThe efficacy and safety of three polyethylene bags commonly used to prevent hypothermia in premature infants was assessed. MethodsTo simulate transfer from the delivery room to a secondary care unit, a thermally stable, bonneted mannequin (skin temperature: 34.4 °C) was placed in a climate chamber under different conditions: with a radiant warmer, with various polyethylene bags (open on one side, closed by a draw-string at the neck, or a “life support pouch” with several access points) or without a bag. ResultsWith the radiant warmer turned on, the mean reduction in heat loss from the nude mannequin was 50.8 ± 1.7% (p < 0.0001, vs. warmer off). The mean reduction in heat loss (vs. no bag) was 55.0 ± 0.9% for the drawstring bag, 49.0 ± 2.2% for the standard bag (p = 0.0001), and 48.1 ± 0.7% for the life support pouch (p = 0.006). When a radiant warmer + polyethylene bag were used, heat stress (body temperature: 38 °C) and severe hyperthermia (40 °C) occurred after 11 and 34 min, respectively. ConclusionCaution must be taken when using a radiant warmer and polyethylene bag with a premature infant. Heat stress can occur in only 11 min. Continuous body temperature monitoring is therefore required.

Admission hypo- and hyperthermia are associated with increased mortality and morbidity in very preterm infants.

Commentary on: Lyu Y, Sha PS, Ye XY, Waree R, Piedboeuf B, Deshpandey A, Dunn M, Lee SK, for the Canadian Neonatal Network. Association between admission temperature and mortality and major morbidity in preterm infants born at fewer than 33 weeks′ gestation. JAMA Pediatr 2015; 169: e150277. Even though the pathophysiologic mechanisms of hypo- and hyperthermia and their impact on infants’ outcome have been known for a long time, most previous research merely covers one end of the temperature scale, namely hypothermia. In this Canadian Neonatal Network study, Lyu et al. retrospectively investigated the effect of admission body temperature (low and high) on adverse outcomes of preterm infants. The nationwide participation resulted in an impressive number of included infants with only very few dropouts. Nevertheless, there are a few comments to make. The authors define the admission temperature as the temperature taken with the first vital signs within the first hour of the infant's admission to the NICU. Information about the infant's chronological age when admission temperature was measured is missing. There is no standard protocol to measure the admission temperature. Not only does the location of temperature acquisition vary (rectal vs. axillary) but also the temperature detecting device. The authors cite Craig et al. 1 who concluded that there is a pooled mean temperature difference of 0.17°C between axillary and rectal temperatures. This indicates only a small – probably not significant – difference between the two measurement locations. They forgot to mention that the range of temperature difference was wide and that the temperature measurement device (mercury vs. electronic) plays an important role. Mercury thermometers had narrower limits of agreement when comparing axillary vs. rectal temperatures. Other studies also come to the conclusion that axillary and rectal temperatures are not interchangeable in preterm infants 2. Important, but not documented, are possible confounders such as the mother's temperature at birth and the time needed to transport the baby from the delivery room to the NICU. Other confounders such as ventilation with a dry circuit and the use of fluids for resuscitation are not mentioned, as well. The authors included factors like these in their infants’ characteristics (Apgar score <7 with five minutes, SNAP II >20, resuscitation needed) and applied a univariate analysis, which showed that these factors were associated with admission temperature. In addition, the primary composite outcome may contain too many individual components. Schmidt et al. 3 presented a count of three major neonatal morbidities, namely bronchopulmonary dysplasia, brain injury and severe retinopathy of prematurity, as the most important prognostic factors for neurodevelopmental outcome at 18 months. Bassler et al. 4 showed that necrotising enterocolitis and sepsis (except meningitis) are weaker predictors of a poor long-term outcome. Late-onset sepsis, on the other hand, has been shown to be inversely correlated with hypothermia 5, which might have been the reason for adding sepsis to the composite primary outcome. For the secondary outcome, the authors calculated the admission temperature at which each single adverse outcome was at its lowest rate. This is interesting on a theoretical basis, but not applicable for clinical everyday life. In conclusion, the authors found an association between hypo- and hyperthermia and an adverse neonatal outcome, which calls for continuous monitoring of body temperature in extremely preterm infants as part of routine resuscitation. https://ebneo.org/2016/11/admission-hypo-and-hyperthermia-are-associated-with-increased-mortality-and-morbidity-in-very-preterm-infants None. None.

Skin Temperature Over the Carotid Artery, an Accurate Non-invasive Estimation of Near Core Temperature.

Background:During anesthesia, continuous body temperature monitoring is essential, especially in children. Anesthesia can increase the risk of loss of body temperature by three to four times. Hypothermia in children results in increased morbidity and mortality. Since the measurement points of the core body temperature are not easily accessible, near core sites, like rectum, are used.Objectives:The purpose of this study was to measure skin temperature over the carotid artery and compare it with the rectum temperature, in order to propose a model for accurate estimation of near core body temperature.Patients and Methods:Totally, 124 patients within the age range of 2 - 6 years, undergoing elective surgery, were selected. Temperature of rectum and skin over the carotid artery was measured. Then, the patients were randomly divided into two groups (each including 62 subjects), namely modeling (MG) and validation groups (VG). First, in the modeling group, the average temperature of the rectum and skin over the carotid artery were measured separately. The appropriate model was determined, according to the significance of the model’s coefficients. The obtained model was used to predict the rectum temperature in the second group (VG group). Correlation of the predicted values with the real values (the measured rectum temperature) in the second group was investigated. Also, the difference in the average values of these two groups was examined in terms of significance.Results:In the modeling group, the average rectum and carotid temperatures were 36.47 ± 0.54°C and 35.45 ± 0.62°C, respectively. The final model was obtained, as follows: Carotid temperature × 0.561 + 16.583 = Rectum temperature. The predicted value was calculated based on the regression model and then compared with the measured rectum value, which showed no significant difference (P = 0.361).Conclusions:The present study was the first research, in which rectum temperature was compared with that of skin over carotid artery, to find a safe location with easier access and higher accuracy for estimating near core body temperature. Results obtained in this study showed that, using a model, it is possible to evaluate near core body temperature in children, by measuring skin temperature over carotid artery.

Body temperature increases during pediatric full mouth rehabilitation surgery under general anesthesia

Background/purposeGeneral anesthesia is necessary for full mouth rehabilitation surgery in children. Pediatric patients are susceptible to developing hypothermia during surgery under general anesthesia. This study reports gradually increased body temperature in pediatric patients receiving full mouth rehabilitation surgery. Materials and methodsFollowing institutional review board approval, the medical records of pediatric patients who received full mouth rehabilitation surgery from 2011 through 2012 were collected. The body temperatures (preoperative, periodic during operation, and postoperative 5 hours and 12 hours) and the maximum differences in temperature change during operation were recorded. ResultsA total of 34 patients were enrolled in this study. An increase in body temperature was found. The mean ± standard deviation of the difference in temperature change was found to be 2.50 ± 1.17°C. A significant positive correlation was noted (r = 0.464, P = 0.006) between the maximum temperature changes and the operation duration. At 12 hours after operation, no patients were reported to have a tympanic temperature >37.5°C. ConclusionBody temperature transiently increased during pediatric full mouth rehabilitation surgery. The increase in body temperature was associated with operation duration. The etiology is uncertain. Continuous body temperature monitoring and the application of both heating and cooling devices during pediatric full mouth rehabilitation surgery should be mandatory.

유한 요소 시뮬레이션을 이용한 이중 매질 심부 체온계의 정확도 평가

Continuous body temperature monitoring is useful and essential in diverse medical procedures such as infection onset detection, therapeutic hypothermia, circadian rhythm monitoring, sleep disorder assessment, and gynecological research. However, the existing thermometers are too invasive or intrusive to be applied to long-term body temperature monitoring. In our previous study, we invented the bi-medium deep body thermometer which can noninvasively and continuously monitor deep tissue temperature. And the ratio of thermal resistances expressed as K-value should be obtained to estimate body temperature with the thermometer and it can be different under various measurement environments. Although the device was proven to be useful through preliminary simulation test and small group of human study, the experimental environment was restrictive in our previous approach. In this study, a finite element simulation was executed to obtain the K-value and evaluate the accuracy of bi-medium thermometer under various measurement environments. In addition, K-value estimation equation was developed by analyzing the influence of 5 measurement environmental factors (medium length, medium height, tissue depth, blood perfusion rate, and ambient temperature) on K-value. The results revealed that the estimation accuracy of bi-medium deep body thermometer based on computer simulation was very high (RMSE < 0.003 o C) in various measurement envi- ronments. Also, bi-medium deep body thermometer based on K-value estimation equation showed relatively accurate results (RMSE < 0.3 o C) except for one case. Although the K-value estimation technology should be improved for more accurate body temperature estimation, the results of finite element simulation showed that bi-medium deep body thermometer could accurately measure various tissue temperatures under diverse environments.