Differences In Skin Temperature Research Articles

Study on personal comfort heating system and human thermal comfort in extremely low-temperature building environments

Exposure to extremely low-temperature building environments around -20 °C causes various hazards to human health. However, few studies have studied human thermal comfort and physiological response in such environments, nor the personal comfort heating system. Thus, this study investigated the heating characteristics of personal comfort heating system, their effects on thermal responses, and thermophysiological parameters in extremely low-temperature building environments. We conducted experimental tests and questionnaires in a cryogenic enthalpy difference laboratory with air temperature ranging from -21.2 to -15.6 °C and a relative humidity of 55 %. Eight experimental conditions were designed with several heating measures (heating mat, heating gloves, heating cushion and airwarmer). The heating parameters of the personal comfort heating systems as well as the subjective evaluations and skin temperature of the subjects were recorded and analyzed. The results showed that the airwarmer confinement box condition had a corrective power of up to 38.3 K. The overall thermal sensation vote and overall thermal comfort vote were maintained at 0.25 and -0.25. Further, we found that the face, hands, calves and feet got cold easier with the largest skin temperature difference of -4.9, -8.1, -6.7 and -7.6 °C, respectively. Besides, the relationships between thermal responses and between thermal responses and skin temperature were examined, as well as a thermal comfort assessment methodology was established for extremely low-temperature environments.

Effect of a vapor barrier in combination with active external rewarming for cold-stressed patients in a prehospital setting: a randomized, crossover field study

BackgroundUse of a vapor barrier in the prehospital care of cold-stressed or hypothermic patients aims to reduce evaporative heat loss and accelerate rewarming. The application of a vapor barrier is recommended in various guidelines, along with both insulating and wind/waterproof layers and an active external rewarming device; however, evidence of its effect is limited. This study aimed to investigate the effect of using a vapor barrier as the inner layer in the recommended “burrito” model for wrapping hypothermic patients in the field.MethodsIn this, randomized, crossover field study, 16 healthy volunteers wearing wet clothing were subjected to a 30-minute cooling period in a snow chamber before being wrapped in a model including an active heating source either with (intervention) or without (control) a vapor barrier. The mean skin temperature, core temperature, and humidity in the model were measured, and the shivering intensity and thermal comfort were assessed using a subjective questionnaire. The mean skin temperature was the primary outcome, whereas humidity and thermal comfort were the secondary outcomes. Primary outcome data were analyzed using analysis of covariance (ANCOVA).ResultsWe found a higher mean skin temperature in the intervention group than in the control group after approximately 25 min (p < 0.05), and this difference persisted for the rest of the 60-minute study period. The largest difference in mean skin temperature was 0.93 °C after 60 min. Humidity levels outside the vapor barrier were significantly higher in the control group than in the intervention group after 5 min. There were no significant differences in subjective comfort. However, there was a consistent trend toward increased comfort in the intervention group compared with the control group.ConclusionsThe use of a vapor barrier as the innermost layer in combination with an active external heat source leads to higher mean skin rewarming rates in patients wearing wet clothing who are at risk of accidental hypothermia.Trial registrationClinicalTrials.gov identifier: NCT05779722.

Hot, cold, or just right? An infrared biometric sensor to improve occupant comfort and reduce overcooling in buildings via closed-loop control

To improve occupant comfort and save energy in buildings, we have developed a closed-loop air conditioning (AC) sensor-controller that predicts occupant thermal sensation from the thermographic measurement of skin temperature distribution, then uses this information to reduce overcooling (cooling-energy overuse that discomforts occupants) by regulating AC output. Taking measures to protect privacy, it combines thermal-infrared (TIR) and color (visible spectrum) cameras with machine vision to measure the skin-surface temperature profile. Since the human thermoregulation system uses skin blood flow to maintain thermoneutrality, the distribution of skin temperature can be used to predict warm, neutral, and cool thermal states. We conducted a series of human-subject thermal-sensation trials in cold-to-hot environments, measuring skin temperatures and recording thermal sensation votes. We then trained random-forest classification machine-learning models (classifiers)—to estimate thermal sensation from skin temperatures or skin-temperature differences. The estimated thermal sensation was input to a PI control algorithm for the AC, targeting a sensation level between neutral and warm. Our sensor-controller includes a sensor assembly, server software, and client software. The server software orients the cameras and transmits images to the client software, which in turn assesses occupant skin temperature distribution, estimates occupant thermal sensation, and controls AC operation. A demonstration conducted in a conference room in an office building near Houston, TX showed that our system reduced overcooling, decreasing AC load by 42% when the room was occupied while improving occupant comfort (fraction of “comfortable” votes) by 15 percentage points.

Analysis of asymmetric thermal sensation under the coupling effect of temperature difference in multiple parts of human body

Responding to thermal comfort based on physiological indicators is a broad and reliable research method. How to use skin temperature to predict thermal comfort in a non-uniform environment is of great significance. 24 volunteers were selected for testing with local radiant heating in Kitakyushu, Japan. It was found that the most obvious skin temperature difference value occurred between left and right thighs while heating after 30 min, which would exceed 5 °C. The asymmetric thermal sensation votings (ATSV) and the skin temperature difference were significantly influenced while changing radiation intensity and radiation distance, the ATSV of the subjects in the small space was about 0.3 lower than that of the subjects in the large space. Increasing the radiation intensity, the TSV of the small space decreased by about −0.5, which can be seen that higher radiation intensity may bring lower value of the TSV. A prediction model of the ATSV and skin temperature difference was established and the sensitivity analysis was performed on the different body parts that significantly affected the ATSV, and the dominant factors affecting the ATSV were obtained. This paper complements the non-uniform thermal environment prediction method.

Temperature Differences Between Controlled Primary Hypothyroidism and Healthy Patients: An Exploratory Study.

Hypothyroidism is conventionally treated with replacement therapy through levothyroxine (LT4). Despite the improvement in symptoms, cold intolerance persists in some patients. The present study aims to determine whether there is a difference in temperature perception and skin temperature between patients with primary controlled hypothyroidism (PCH) and a group of healthy controls matched for body mass index and age. Secondarily we aimed to determine difference in quality of life. Skin temperature measurements were performed in both groups, both in the central and peripheral regions of the body. In addition, subjects were asked about their perception of temperature in a temperature-controlled room; anthropometric measurements were taken, their quality of life was assessed using the ThyPRO-39, and a thyroid hormone profile was performed. Eleven patients in the PCH group and 30 patients in the control group were studied. It was found that the group with PCH presented a significantly lower palmar temperature than the control group [mean (SD) of 32.05 (1.79) vs 33.10 (1.30) oC, P = .046]. A mediation model showed a direct effect. Temperature perception was equal between groups. The median (interquartile range) of ThyPRO was 8 (5.2) points in the control group vs 21.8 (13.5) in the group of controlled hypothyroidism, P < .001. These results suggest that, despite LT4 treatment, patients continue to present abnormalities in thermogenesis-related thermogenesis, and this may be due to a lack of hormonal adaptation to environmental changes and physiological demands, leading to lower body temperatures and increased sensitivity to cold.

Comparative study on the efficacy of PRP gel and UC-MSCs gel as adjuvant therapies in the treatment of DFU wounds.

Diabetic foot ulcer (DFU) is a common and serious complication of diabetes, and its treatment is challenging. Platelet-rich plasma (PRP) gel and umbilical cord mesenchymal stem cells (UC-MSCs) gel have been concerned as new therapies for DFU in recent years, and comparative studies on the efficacy and mechanisms of these methods, however, are rarely reported. Thirty patients with DFU were selected and divided into the PRP group and the UC-MSCs group, and wound healing, foot blood vessels (ABI index), infection index (CRP), neuropathy symptoms (TCSS score), and foot skin temperature before and after treatment were compared between the two groups. SPSS 21.0 was used for statistical analysis. The results showed that the efficacy of the UC-MSCs gel group was significantly better than that of the PRP group in terms of wound healing rate, time to complete wound closure, ABI index, CRP level and TCSS score. No statistically significant difference in foot skin temperature was observed between the two groups. The efficacy of UC-MSCs gel is significantly superior to that of PRP gel in the treatment of DFU, with shortened time to complete wound closure, increased wound healing rate, better pain and infection control, and improved vascular and neurological symptoms.

Combining protection with skin health: In vivo studies of an innovative gelatin/tannic acid-based hydrogel patch to prevent PPE-related skin lesions

The prolonged use of Personal Protective Equipment (PPE) can lead to skin problems due to persistent pressure, friction, and tension. This issue has prompted the exploration of solutions to protect the skin while maintaining the effectiveness of the PPE. This study aimed to evaluate the in vivo effectiveness of a gelatin/tannic acid-based hydrogel patch positioned beneath a mask to alleviate skin damage resulting from mask-wearing. To understand the pressure exerted by PPE, in vitro tests were conducted to measure the tensile strength of three types of facial masks. The FFP2 masks exhibited the highest tensile strength and were selected for subsequent in vivo biometric investigations. Biometric parameters were evaluated using the Flir E50bx® thermographic camera, Corneometer®, MoistureMap®, Sebumeter®, Tewameter®, and VISIA® systems. The results showed that when the hydrogel patch was used under the mask, there were no significant differences in facial skin temperature, sebum levels, or TEWL values (p > 0.05). However, a statistically significant increase in skin hydration and a decrease in frontal redness (p < 0.05) were observed. Consumer acceptance was assessed through sensory analysis questionnaires. In summary, the observed attenuation of physiological changes in the facial area and the positive consumer feedback suggest that this polymeric film-forming system is a simple yet effective solution to prevent PPE use-related skin issues.

Thermal sensation prediction model for high-speed train occupants based on skin temperatures and skin wettedness.

Passenger thermal comfort in high-speed train (HST) carriages presents unique challenges due to factors such as extensive operational areas, longer travel durations, larger spaces, and higher passenger capacities. This study aims to propose a new prediction model to better understand and address thermal comfort in HST carriages. The proposed prediction model incorporates skin wettedness, vertical skin temperature difference (ΔTd), and skin temperature as parameters to predict the thermal sensation vote (TSV) of HST passengers. The experiments were conducted with 65 subjects, evenly distributed throughout the HST compartment. Thermal environmental conditions and physiological signals were measured to capture the subjects' thermal responses. The study also investigated regional and overall thermal sensations experienced by the subjects. Results revealed significant regional differences in skin temperature between upper and lower body parts. By analyzing data from 45 subjects, We analyzed the effect of 25 variables on TSV by partial least squares (PLS), from which we singled out 3 key factors. And the optimal multiple regression equation was derived to predict the TSV of HST occupants. Validation with an additional 20 subjects demonstrated a strong linear correlation (0.965) between the actual TSV and the predicted values, confirming the feasibility and accuracy of the developed prediction model. By integrating skin wettedness and ΔTd with skin temperature, the model provides a comprehensive approach to predicting thermal comfort in HST environments. This research contributes to advancing thermal comfort analysis in HST and offers valuable insights for optimizing HST system design and operation to meet passengers' comfort requirements.

Venous dilation effect of hot towel (moist and dry heat) versus hot pack for peripheral intravenous catheterization: a quasi-experimental study

BackgroundHeat application before peripheral intravenous catheterization is recommended for venous dilation. Hot pack application enlarges the venous diameter in healthy adults; however, hot towels (moist and dry heat) are used often in some medical cases. However, it is unclear whether hot towel application promotes venous dilation better than hot pack application. This study compared the venous dilation effect of using a hot towel (moist and dry heat) to a hot pack before applying the tourniquet at an access site for peripheral intravenous catheterization.MethodsEighty-eight healthy females aged 18–29 years were recruited for this quasi-experimental study. They underwent three types of heat applications (hot pack, moist hot towel, and dry hot towel [moist hot towel wrapped in a dry plastic bag], all of which were warmed to 40 ± 2 °C and performed for 7 min) to their forearm and tourniquet application for 30 s after each heating. Venous diameter and depth were measured using ultrasonography, and venous palpability and visibility (venous assessment score) was observed as venous dilatation effects. In addition, the skin temperature, stratum corneum hydration, and subjective evaluation of the warmth were measured.ResultsThere were no significant differences in venous diameter and assessment scores after intervention between the dry hot towel and the hot pack groups, and the effect size was negligible (Cohen’s d < 0.20). However, these measurements were significantly lower for the moist hot towel than for the other two heat applications (P < .001). Although there was no significant difference in skin temperature and warmth rating score between the dry hot towel and the hot pack, these were significantly lower for the moist hot towel than for the other two heat applications (P < .001). The amount of change in stratum corneum hydration of the dry hot towel was not significantly different from that of the hot pack; however, that of the moist hot towel was significantly larger than that of the other two heat applications (P < . 001.)ConclusionsA method in which a towel warmed in hot water is wrapped in a dry barrier may be an alternative to a hot pack.Trial registrationThis study was registered with University Hospital Medical Information Network in Japan (Registration No.: UMIN000048308. Registered on July 7, 2022).

Increases in local skin temperature correlate with spontaneous foot lifting and heat hyperalgesia in both incisional inflammatory models of pain.

This study investigated if a localized increase in skin temperature in rat models of incisional and inflammatory pain correlates with the intensity of spontaneous and evoked pain behaviors. Anesthetized rats received either a 20-mm longitudinal incision made through the skin, fascia, and muscle of the plantar hind paw or an injection of complete Freund adjuvant into the plantar hind paw of anesthetized rats to induce local inflammation. Spontaneous and evoked pain behaviors were assessed, and changes in skin temperature were measured using a noncontact infrared thermometer. There were no differences in skin temperature between the ipsilateral and contralateral hind paw before the incision or inflammation. Skin temperature increased at 2 hours after hind paw plantar incision or 1 day after inflammation of the affected paw, which gradually returned to baseline by the first day and fourth days after treatment, respectively. The increase in skin temperature correlated with the intensity of spontaneous pain behaviors and heat but not with mechanical allodynia. Our results suggest that a simple measurement of localized skin temperature using a noncontact infrared thermometer could measure the extent of spontaneous pain behaviors and heat hyperalgesia following plantar incision or inflammation in animals. In the absence of a reliable objective marker of pain, these results are encouraging. However, studies are warranted to validate our results using analgesics and pain-relieving interventions, such as nerve block on skin temperature changes.

Experimental evaluation of partial body cryotherapy unit with gas supply regulation

The partial body cryotherapy is a medical treatment that uses a physical factor to stimulate the main part of body surface. Today physicians do not have the technical ability to improve this method towards predictive and personalized medicine. Different patients have different dimensions and other features (physique, sex, age, adaptation level, etc.). However, physicians are able to set only the exposure duration. In this case, the skin cooling uncertainty and non-uniformity reduces the safety and effectiveness of cryoexposure. The key to upgrade cryotherapy is increasing the number of parameters to achieve a less skin temperature difference at the end of exposure and to plan a given skin cooling for different patients by reducing the intensity of cooling. This article is aimed to experimentally evaluate the novel partial body cryotherapy unit that has the ability to regulate: the gas temperature in the cryocabin; the inlet jet direction and the exposure duration. Based on the proposed model of a human as an object of cooling, using the developed unit, the adopted cryoexposure protocol and the presented approach to the analysis of infrared images, experiments were conducted. Data were obtained on the participant's interview and skin temperature. It is shown that the approach used is safety treatment and make it possible to obtain an improved and controlled skin temperature distribution at the end of cryoexposure. It might be relevant for improving cryotherapy protocols and for equipment development.

Analysing the impact of cloth fabrics on skin temperature during and after exercise using an FDM model

This study presents a 1D finite difference model that examines the influence of cloth fabrics on skin temperature during and after exercise, considering the complex nature of the human body and its susceptibility to infections and viruses. The aim is to design comfortable, high-quality fabrics that minimize potential issues caused by body temperature fluctuations. The model incorporates various physical, physiological, and thermal parameters of cloth to develop protective clothing suitable for exercise. Numerical results were compared to previous studies that analyzed skin temperature without clothing to validate the model’s accuracy. The findings indicate a minimal difference in skin temperature when wearing cotton and polyester cloth, with polyester fabric demonstrating superior characteristics such as stretchability, durability, and sweat resistance. The thermal information obtained from this model can be utilized to design appropriate clothing for diverse weather conditions, ultimately enhancing the performance and comfort of athletes, military personnel, and individuals engaged in physically demanding work. Additionally, the model can aid in developing thermal stress protocols for infection treatment and provide guidelines for physical activity to promote healthy living. This research contributes to the field of materials research by offering valuable insights into the design and development of protective clothing for exercise. By understanding the impact of cloth fabrics on skin temperature, advancements can be made in creating clothing that optimizes human comfort and performance.

Improvement and validation of the Tanabe model to simulate human thermal behaviors in hot environments at high altitudes

Exposure to hypobaric and hyperthermic environments can easily induce heat stress and affect operational efficiency. Thermal manikins represent advanced instruments for simulating human thermal behaviors in complex ambient conditions. However, currently, no thermal manikins are coupled with a human thermoregulatory model adapted for high-altitude environments. This study aimed to develop the traditional Tanabe model by incorporating air pressure into the calculation of the convective and evaporative heat transfer coefficients, therefore local skin temperature and thermal sensation at high altitudes could be predicted. To validate the model, these predicted variables were also measured in human thermal physiology experiments at the altitude of 0 m (101.3 kPa) and 4000 m (56.04 kPa) with an ambient temperature of 35 °C. The results demonstrated that local and weighted average skin temperatures were consistent between simulation and experimental results. The maximum deviation between experiments and simulation did not exceed 0.7 °C at segments except hand and foot, and 2.5 °C at each segment, at the altitude of 0 m and 4000 m respectively. The R2 values of Gaussian distribution and linear regression results concerning the experimental and simulation weighted average skin temperature and the PMV score at the altitudes of 0 m and 4000 m were 0.966, 0.975, 0.857, and 0.851. These findings suggest that differences in skin temperature and thermal sensation at different altitudes are influenced by variations in evaporation and dry heat exchanges. The improved Tanabe model in this study was validated and could be further utilized in investigating heat transfer processes and coefficients between the skin surface and the environment and developing control algorithms for thermal manikins.

The use of infrared thermography for non-invasive detection of bleeding and musculoskeletal abnormalities in patients with hemophilia: an observational study

BackgroundIn patients with hemophilia (PwH), bleeding often occurs in joints and muscles, and early detection of hemorrhage is important to prevent the onset and progression of mobility impairment. Complex-Image analysis such as ultrasonography, computed tomography, and magnetic resonance imaging are used to detect bleeding. On the other hand, no simple and rapid method to detect the active bleeding has been reported. Local inflammatory responses occur when blood leaks from damaged vessels, and the temperature at the site of active bleeding could be expected to increase in these circumstances, leading to an increase in surrounding skin temperature. Therefore, the purpose of this study was to investigate whether the measurement of skin temperature using infrared thermography (IRT) can be used as a diagnostic aid to detect active bleeding.MethodsFifteen PwH (from 6 to 82 years old) complaining of discomfort such as pain were examined. Thermal images were obtained simultaneously at the affected sides and comparable unaffected sides. The average skin temperature of the affected side and of the unaffected side were measured. The temperature differences were calculated by subtracting the average skin temperature at the unaffected side from the affected side.ResultsIn eleven cases with active bleeding, the skin temperature at the affected side was more than 0.3 °C higher (0.3 °C to 1.4 °C) compared to the unaffected side. In two cases without active bleeding, there were no significant differences in skin temperature between the affected and unaffected sides. In two cases with previous rib or thumb bone fracture, the skin temperature at the affected side was 0.3 °C or 0.4 °C lower than that of the unaffected side, respectively. In two cases with active bleeding in which longitudinal evaluation was conducted, the difference in skin temperature decreased after hemostatic treatment.ConclusionThe analysis of skin temperature deference using IRT was a useful supportive tool to readily assess musculoskeletal abnormalities and bleeding in PwH as well as to determine the success of the hemostatic treatment.

Skin Temperature of Acupoints in Health and Primary Dysmenorrhea Patients: A Systematic Review and Meta-Analysis.

Dysmenorrhea is a common clinical condition and some studies shown that the skin temperature of some acupoints changes in primary dysmenorrhea (PD) patients. This study aimed to evaluate the changes in skin temperature at specific acupoints in PD patients and healthy subjects. The literature for assessing skin temperature at acupoints in PD patients and healthy subjects was searched in eight databases. The literatures obtained from the search was independently screened by two authors, and the quality of the included articles was evaluated using the consensus checklist of the Thermographic Imaging in Sports and Exercise Medicine (TISEM) and the Newcastle-Ottawa Scale (NOS) scale. The skin temperature of the relevant acupoints or the difference between the left and right acupoints of the same name was used as the outcome during any period of menstruation. Finally, the meta-analysis was performed using RevMan 5.4.1 software to evaluate the changes in skin temperature in the related acupoints. Seven eligible studies were included, which included 328 patients with PD and 279 healthy subjects. The results of the meta-analysis revealed a significant difference in skin temperature around the Sanyinjiao (SP6)(MD: 0.04, 95% CI: 0.00, 0.08), Xuehai (SP 10)(MD: -0.07, 95% CI:-0.11, -0.02) and Taixi (KI 3)(MD: 0.06, 95% CI:0.01, 0.11) acupoints between PD and healthy subjects. PD patients also showed a difference in skin temperature at the Taixi (KI 3)(MD: 0.14, 95% CI:0.04, 0.24), Shuiquan (KI 5)(MD: 0.11, 95% CI: 0.03,0.19), Taichong (LR 3)(MD: -0.10, 95% CI: -0.19,-0.01), Diji (SP 8)(MD: -0.09, 95% CI: -0.16, -0.01), and Xuehai (SP 10)(MD: -0.14, 95% CI: -0.23, -0.06) acupoint areas at different times of menstruation compared to that of healthy subjects, as revealed by the subgroup analysis. Primary dysmenorrhea patients showed some differences in the skin temperature of the special acupoints are as Sanyinjiao (SP6), Diji (SP 8), Xuehai (SP 10), Shuiquan (KI 5), Taichong (LR 3), and Taixi (KI 3) compared with healthy subjects. CRD42022381387.

손 냉각과 압박이 조합된 항암 치료용 장갑이 손의 혈관 수축 및 국소 감각에 미치는 영향

This study investigated the combined effects of wrist compression and hand cooling on cutaneous vasoconstriction of the hands to develop chemotherapy gloves that alleviate side-effects of anti-cancer treatments. Eight healthy young females (23 ± 3 y in age, 162 ± 4 cm in height, 60 ± 8 kg in weight, 22.6 ± 3.0 kg•mSUP-2/SUP in body mass index, 29.0 ± 6.6 % body fat) participated in the following three experimental conditions: cooling only with 14℃ (CO), cooling & intermittent compression (CIC), and cooling & continuous compression (CCC). The results showed 1) no significant differences in finger skin blood flow(%) or finger skin temperature among the three conditions, 2) no significant difference in hand skin temperature between the CO and CCC or CIC conditions, and 3) no significant differences in overall thermal sensation or thermal comfort among the three conditions. However, subjects felt more wrist and hand pressure and tingle sensations in the CIC (pressure phase) and CCC conditions than in the CO condition (P0.001). In conclusion, we did not find any synergistic effects on hand skin vasoconstriction from adding wrist compression to hand cooling, and the pressure and tingling sensations were deteriorated by adding the compression band. Therefore, we suggest cooling the hands at 14oC during cancer treatments, rather than adding compression with cooling.

Early Skin Temperature Characteristics of the Kennedy Lesion (Kennedy Terminal Ulcer)

BACKGROUND: Pressure injuries are associated with skin temperature changes, but little is known about skin temperature characteristics of the Kennedy Lesion (KL). PURPOSE: The purpose of this study was to describe early skin temperature changes in KLs using long-wave infrared thermography. METHODS: KLs were identified from chart review in 10 ICU patients. Skin assessments were performed within 24 hours of new skin discoloration.  Temperature measurements were performed using a long-wave infrared thermography imaging system. Relative Temperature Differential (RTD) between the discolored area and a selected control point was calculated.  RTDs of &gt; +1.2 °C and &lt; -1.2 °C were considered abnormal. Demographic data and observable characteristics of the KL were collected when available.  Descriptive statistics (Mean +/- SD; %) were used. RESULTS: The major finding of this study was that there were no early skin temperature differences between the KLs and surrounding skin. CONCLUSION: The early stage of the KL may be limited to microvascular injury which results in a normal skin temperature. More studies are needed to verify this finding and to ascertain whether KL skin temperature changes over time. The study also supports the bedside use of thermography in skin temperature assessment.

Lumbar Sympathetic Trunk Injury: An Underestimated Complication of Oblique Lateral Interbody Fusion.

Lumbar sympathetic trunk (LST) injury is one of the major complications after oblique lumbar interbody fusion (OLIF). LST injury often manifests as unequal skin temperature in lower limbs after operation, and there may be a large number of missed diagnoses due to the lack of attention and different diagnostic methods. The study aimed to investigate the incidence and clinical characteristics of LST injury after OLIF. The data of patients with lumbar degenerative diseases who underwent OLIF in our hospital from April 2016 to October 2017 were retrospectively analyzed. Finally, a total of 54 patients were included. There were 10 males and 44 females, aged 58.4 ± 10.9 years. The skin temperature of lower limbs was measured before and a day after surgery. The patients were followed up at 1 week, 6 weeks, 6 months, and 2 years after the surgery. Likert five-point scale was used to evaluate the discomfort caused by LST injury. Injury severity score was introduced to grade injury degree according to the recovery time of postoperative symptoms. The chi-square test was used to analyze the association of incidence of lumbar sympathetic trunk (LST) injury with contributing factors, such as gender and number of surgical segments. The unequal temperature was not found before surgery in all the patients. Postoperatively, 16 cases (29.6%) had difference of skin temperature more than 0.5°C and were diagnosed with LST injury. Eight patients (14.8%) had self-perception of skin temperature differences, and 12 patients (22.2%) had other symptoms, such as muscle pain, numbness, and weakness, which were not statistically different between patients with and without lumbar sympathetic trunk injury (p > 0.05). In the 16 patients with LST injury, the difference of skin temperature between the two legs was 0.6 ± 0.1 °C on the first day, and the temperature difference lasted for 1.5-~12months. According to Likert five-point scale, two cases (12.5%) were poor, and 14 cases (87.5%) were moderate immediately after surgery. Fifteen cases improved to some extent 6 weeks to 12months after surgery. Postoperative LST injury is mainly manifested by different temperature of lower limbs. The incidence was higher in patients with multi-segment OLIF than in those with single-segment OLIF, and the subjective experience of most patients with LST injury was moderate discomfort.

Preliminary assessment of the reliability and validity of infrared skin temperature measurements in Rett syndrome.

As clinical trials for Rett syndrome are underway, there is a need to validate potential supplemental outcome measures that reflect important signs and symptoms. Autonomic dysfunction, particularly vasomotor dysfunction, is one potential area for which biomarkers could be developed. In the current study, infrared thermal images of hands and feet from 26 females with Rett syndrome (aged 62months to 39years), and 17 females without known intellectual, genetic or neurological disorders (aged 55months to 39years) were collected. Between-group differences in skin temperature, and temporal stability of skin temperature measures in the Rett syndrome group, and relationships between skin temperature measures and parent-reported and researcher-evaluated indicators of autonomic dysfunction were evaluated. Between-group differences showed lower hand and foot temperatures in the Rett syndrome group. Hand temperature measurements were stable over time and were moderately correlated with parent-reported autonomic symptoms. Foot temperature measurements were more variable than hand temperatures but showed stronger correlations with parent-reported autonomic symptoms. The results provide preliminary support for the reliability and validity of hand and foot skin temperature measures in Rett syndrome. Additional research is needed to replicate these results and evaluate the temporal stability of these measures over shorter time scales.

Implications of lower indoor temperatures – Not cool for cold susceptible individuals across both sexes

Wider temperature ranges in buildings can reduce building energy use and prevent shortage of energy availability. However, humans do not perceive temperature equally and a general lowering of indoor temperature may in particular impact susceptible individuals. The discrepancy between individuals has been ascribed to sex differences, but is not well understood and could relate to heterogeneity in endogenous heat production or other personal parameters. We, therefore, evaluated individual thermal responses including physiological measurements of metabolic heat production in both men and women, identified, and via experiments, verified as cold sensitive or cold resilient. On average, the cold sensitive group had an 18 % lower resting metabolic rate compared to the cold resilient group when controlling for clothing and other important parameters for heat exchange. We observed a 0.9 °C difference in neutral temperature between sexes, but no difference in thermal perception or skin temperature. We concluded that cold susceptibility is not simply a matter of perception, but relates to a measurable difference in endogenous heat production. Currently mandated temperature setpoints at workplaces or recommended household temperatures do therefore not seem to discriminate between sexes as a result of sex-related differences in physiology, but they might have negative implications for cold sensitive individuals.