Comparison of two non-invasive body temperature measurement methods for the detection of febrile neutropenia in children with cancer.

BACKGROUND: This study was conducted to compare the accuracy of two noninvasive thermometers (axillary and infrared non-contact forehead thermometer) in measuring core temperature compared to the gold standard oral thermometer in the detection of fever in pediatric cancer patients with febrile neutropenia. METHODS: The study was conducted with a single group of 42 children with febrile neutropenia between 23 December 2020 and 25 January 2023 in the pediatric hematology and oncology clinic of a training and research hospital, which provides a specialized environment for both medical education and advanced scientific research in the field of pediatric hematology and oncology. The participants' body temperature was measured with an oral, axillary, and non-contact infrared forehead thermometer immediately after admission to the clinic and at 5 and 10 min after admission. The inter-rater agreement for each method and inter-method agreement between axillary and non-contact infrared temperature readings and oral readings were analyzed for each time point using intraclass correlation coefficients (ICC). RESULTS: The children in the study had a mean age of 11.62 ± 3.00 years and 28 (66.7%) were boys, 19 (45.2%) were younger children (5-10 years of age), and 23 (54.8%) were adolescents (11-16 years of age). In the analysis of agreement between the thermometers at admission and at 5 and 10 min after admission in children with febrile neutropenia, the highest agreement was between the oral and axillary thermometers (ICC: 0.584, 0.835, 0.536, respectively) and the lowest agreement was between the oral and non-contact infrared thermometers (ICC: 0.219, 0.022, 0.473, respectively). CONCLUSION: Compared to orally measured body temperature, axillary temperature readings showed better agreement than non-contact infrared temperature readings from the forehead in pediatric patients with febrile neutropenia. PRACTICE IMPLICATIONS: The research findings may guide nurses and families caring for pediatric patients with febrile neutropenia and should contribute to the prevention of false findings of fever and the reduction of its adverse consequences.

Effects of neuromuscular taping form I on wound temperature and erythema in diabetic foot ulcer: a preliminary study.

OBJECTIVE: This study aimed to measure the effectiveness of neuromuscular taping (NMT) form I (a polyacrylate tape 0.6cm wide and 30cm long) on wound temperature and erythema in diabetic foot ulcers (DFUs) as an initial study in NMT intervention trials. METHOD: The study employed a quasi-experimental pretest and post-test design with a seven-day observation. The research sample was 38 patients with DFU grades 2 and 3. The sample was divided into two groups: the control group (n=19) and the intervention group (n=19). In wound care, the modern dressing was applied to both groups while NMT was applied to the intervention group in form I with 30cm long and 6mm wide strips, and on the proximal, distal and lateral sides. The wound bed temperature was measured with a non-contact infrared thermometer, and erythema was measured with Corel Photo-Paint X5 software (Corel Corp, Canada). Statistical analysis between the two groups was carried out using the Mann-Whitney test, independent t-test and Chi-squared test with p< 0.05 representing statistical significance. RESULTS: The preliminary results revealed that no statistically significant differences (p>0.05) were noted between the groups in sociodemographic or clinical characteristics, including age, body mass index, blood sugar, duration of diabetes, sex, smoking history, wound temperature and degree of erythema. Finally, it was also observed that, after seven days of application, NMT form I increased wound bed temperature, and reduced the level of erythema (p<0.05). CONCLUSION: In this study, NMT form I has been shown to increase the wound bed temperature and reduce the degree of erythema in DFUs.

The potential of in ovo-fed amino acids to alleviate the effects of heat stress on broiler chickens: effect on performance, body temperature, and oxidative status during the finisher phase.

The aim of the current study was to investigate the potential of in ovo-fed amino acids (AA) to reduce the effects of heat stress on finishing broiler chickens. To achieve this, a total of 1,400 fertile hatching eggs were randomly distributed into 5 groups (n = 280/group) and injected with one of the following in ovo treatments on embryonic day 18: 52 µL of sterile diluent/egg (CTRL), CTRL + 1.0 mg of L-Leucine (T1), CTRL + 0.45 mg of leucine + 1.15 mg of methionine (T2), CTRL + 3.0 mg of methionine + 2.0 mg of cysteine (T3), and CTRL + 0.40 mg of leucine + 1.60 mg of methionine + 1.60 mg of cysteine (T4). After hatch, chicks were allocated according to a complete randomized block design comprising 2 thermal conditions: thermoneutral (24°C, 45% RH) and heat stress (34°C, 55-60% RH) with 5 pens/group/condition. The cyclical heat stress regimen (10 h/d) was then applied from d 29 to d 34. Compared to the CTRL group, T3 and T4 exhibited a higher BW during the starter phase (P < 0.001). T4 also had a lower feed conversion ratio (FCR) than CTRL during this same phase (P = 0.03). During the grower phase, males of all treatment groups consistently exhibited higher BW compared to the CTRL group, which was not observed among female birds (PSex × TRT = 0.005). During the finisher phase, the in ovo treatment effect on performance was not significant. However, heat-stressed birds from treatment group T3 and T4 exhibited lower facial temperatures (Pday × TRT < 0.001) as well as lower plasma (Pcondition x TRT = 0.039) and liver (Pcondition x TRT < 0.001) malonaldehyde concentrations compared to the CTRL group. In conclusion, in ovo-fed AA have the potential to modulate the effects of heat stress on finishing broiler chickens by limiting its detrimental consequences, including increased body temperature and oxidative damage.

Monitoring Intrarenal temperature changes during Ho: YAG laser lithotripsy in patients undergoing retrograde intrarenal surgery: a novel pilot study.

Ho: YAG laser lithotripsy is widely used for urinary stone treatment, but concerns persist regarding its thermal effects on renal tissues. This study aimed to monitor intrarenal temperature changes during kidney stone treatment using retrograde intrarenal surgery with Ho: YAG laser. Fifteen patients were enrolled. Various laser power settings (0.8 J/10 Hz, 1.2 J/12 Hz) and irrigation modes (10 cc/min, 15 cc/min, 20 cc/min, gravity irrigation, and manual pump irrigation) were used. A sterile thermal probe was attached to a flexible ureterorenoscope and delivered into the calyceal system via the ureteral access sheath. Temperature changes were recorded with a T-type thermal probe with ± 0.1 °C accuracy. Laser power significantly influenced mean temperature, with a 4.981 °C difference between 14 W and 8 W laser power (p < 0.001). The mean temperature was 2.075 °C higher with gravity irrigation and 2.828 °C lower with manual pump irrigation (p = 0.038 and p = 0.005, respectively). Body mass index, laser power, irrigation model, and operator duty cycle explained 49.5% of mean temperature variability (Adj. R2 = 0.495). Laser power and operator duty cycle positively impacted mean temperature, while body mass index and specific irrigation models affected it negatively. Laser power and irrigation rate are critical for intrarenal temperature during Ho: YAG laser lithotripsy. Optimal settings and irrigation strategies are vital for minimizing thermal injury risk. This study underscores the need for ongoing research to understand and mitigate thermal effects during laser lithotripsy.

[Association between intraoperative hypothermia and outcomes in neonatal patients undergoing non-cardiac surgery].

Objective: To investigate the impact of intraoperative hypothermia on postoperative outcome in neonatal patients undergoing non-cardiac surgery. Methods: The data of 1 008 neonates undergoing non-cardiac surgery in Children's Hospital, Zhejiang University School of Medicine from January 2020 to October 2022 were retrospectively collected,which included 558 males and 450 females, with a midian age [M (Q1, Q3)] of 6 (2, 14) days. Neonates were divided into 4 groups according to whether hypothermia (below 36 ℃) occurred and the lowest body temperature during the surgery: normal temperature group (n=246), mild hypothermia group (the lowest temperature ranged 35.0-35.9 ℃, n=434), moderate hypothermia group (the lowest temperature ranged 34.0-34.9 ℃, n=232) and severe hypothermia group (the lowest temperature<34 ℃, n=96). The primary outcome was the incidence of intraoperative hypothermia. The four groups' difference of postoperative hospital stay, postoperative mortality within 30 days, postoperative pulmonary complications, postoperative hemorrhage/blood transfusion and acidosis were compared. Multivariate logistic regression was used to analyze the relationship between intraoperative hypothermia and prolonged postoperative hospital stay (>14 d), 30 d-mortality and other complications. Results: In the 1 008 neonatal patients, 762 (75.6%) cases suffered intraoperative hypothermia, among which the incidence of mild, moderate and severe hypothermia was 43.1% (434/1008), 23.0% (232/1008) and 9.5% (96/1008), respectively. The postoperative hospital stay in normal, mild, moderate and severe hypothermia groups was 9.0 (5.8, 18.0), 12.0 (7.0, 21.0), 17.0 (10.0, 34.5) and 31.5 (12.5, 55.8) days. The mortality rate with 30 days after surgery was 2.9% (7/246), 4.4% (19/434), 6.9% (16/232) and 14.7% (14/96), the incidence of postoperative pulmonary complications was 31.7%(78/246), 39.9%(173/434), 44.8%(104/232) and 67.4%(64/96), the rate of postoperative hemorrhage/blood transfusion was 19.9%(49/246), 32.3%(140/434), 49.1%(114/232) and 79.0%(75/96), and the incidence of acidosis was 26.8%(66/246), 35.7%(155/434), 44.4%(103/232) and 46.3%(44/96), respectively. All differences were statistically significant (all P<0.05). According to the adjusted logistic regression analysis, compared with the normal body temperature group, severe hypothermia was associated with prolonged postoperative hospital stay (OR=1.962, 95%CI: 1.063-3.619) and postoperative pulmonary complications (OR=2.020, 95%CI: 1.149-3.553). The mild, moderate and severe hypothermia group could increase the risk of postoperative blood/transfusion rate (mild: OR=1.690, 95%CI: 1.080-2.644; Moderate: OR=2.382, 95%CI: 1.444-3.927; Severe: OR=8.334, 95%CI: 3.123-8.929). The mild and moderate hypothermia could raise the risk of acidosis (mild: OR=1.458, 95%CI: 1.009-2.107; Moderate: OR=1.949, 95%CI: 1.279-2.972). Conclusion: Intraoperative hypothermia can prolong the postoperative hospital stay, and increase the risk of postoperative mortality, postoperative pulmonary complications, postoperative hemorrhage/transfusion, and acidosis.

Identification of hypothermia-inducing neurons in the preoptic area and activation of them by isoflurane anesthesia and central injection of adenosine.

Hibernation and torpor are not passive responses caused by external temperature drops and fasting but are active brain functions that lower body temperature. A population of neurons in the preoptic area was recently identified as such active torpor-regulating neurons. We hypothesized that the other hypothermia-inducing maneuvers would also activate these neurons. To test our hypothesis, we first refined the previous observations, examined the brain regions explicitly activated during the falling phase of body temperature using c-Fos expression, and confirmed the preoptic area. Next, we observed long-lasting hypothermia by reactivating torpor-tagged Gq-expressing neurons using the activity tagging and DREADD systems. Finally, we found that about 40-60% of torpor-tagged neurons were activated by succeeding isoflurane anesthesia and by icv administration of an adenosine A1 agonist. Isoflurane-induced and central adenosine-induced hypothermia is, at least in part, an active process mediated by the torpor-regulating neurons in the preoptic area.

Normothermia to Decrease Surgical Site Infection Risk: Silver Bullet or Fool's Gold? A Retrospective Cohort Study.

PURPOSE: Surgical site infection (SSI) is the leading cause of nosocomial infections among surgical patients in the United States. Currently, there is compelling evidence suggesting that temperature dysregulation in surgical patients may be a risk factor for the development of SSI. We examined the relationship between perioperative hypothermia (PH) and SSI in a population of surgical patients with diabetes mellitus (DM). METHODS: This retrospective cohort review was conducted on patients with a history of DM undergoing orthopaedic surgery at our institution between May 1, 2018, and April 1, 2022. Inclusion criteria were age older than 15 years, a history of DM or recent hemoglobin A1c concentration of ≥6.5%, and operation of at least 60 minutes under general anesthesia. Perioperative hypothermia was defined as an intraoperative temperature ≤ 35.5°C. Continuous variables were compared using the t-test and Wilcoxon rank-sum test. Categorical variables were compared using the chi-squared test. We constructed a multivariable logistic regression model to estimate SSI risk while controlling for demographic variables. RESULTS: A total of 236 patients were included in the final analysis. The overall incidence of SSI was 5.93%. 99 patients (42%) experienced PH. No difference was observed in the risk of SSI between the normothermic and hypothermic cohorts. Among the 99 patients who experienced PH, increasing HbA1c was associated with increasing risk of SSI (OR = 2.39, 95% CI = 1.12 to 5.32, P-value = 0.0222). The multivariable logistic regression model had good discriminatory ability (c-statistic 0.74, 95% CI: 0.61 to 0.89) and good predictive accuracy (sensitivity 64%, specificity 73%). DISCUSSION: PH is not an independent risk factor of SSI. However, in the presence of elevated HbA1c, PH may more than double the risk of SSI. Perioperative hypothermia may be an additive risk factor in the setting of poor glycemic control and potentially in the setting of other known risk factors.

External auricle temperature enhances ear-based wearable accuracy during physiological strain monitoring in the heat.

Body core temperature (Tc) monitoring is crucial for minimizing heat injury risk. However, validated strategies are invasive and expensive. Although promising, aural canal temperature (Tac) is susceptible to environmental influences. This study investigated whether incorporation of external auricle temperature (Tea) into an ear-based Tc algorithm enhances its accuracy during multiple heat stress conditions. Twenty males (mean ± SD; age = 25 ± 3 years, BMI = 21.7 ± 1.8, body fat = 12 ± 3%, maximal aerobic capacity (VO2max) = 64 ± 7 ml/kg/min) donned an ear-based wearable and performed a passive heating (PAH), running (RUN) and brisk walking trial (WALK). PAH comprised of immersion in hot water (42.0 ± 0.3 °C). RUN (70 ± 3%VO2max) and WALK (50 ± 10%VO2max) were conducted in an environmental chamber (Tdb = 30.0 ± 0.2 °C, RH = 71 ± 2%). Several Tc models, developed using Tac, Tea and heart rate, were validated against gastrointestinal temperature. Inclusion of Tea as a model input improved the accuracy of the ear-based Tc algorithm. Our best performing model (Trf3) displayed good group prediction errors (mean bias error = - 0.02 ± 0.26 °C) but exhibited individual prediction errors (percentage target attainment ± 0.40 °C = 88%) that marginally exceeded our validity criterion. Therefore, Trf3 demonstrates potential utility for group-based Tc monitoring, with additional refinement needed to extend its applicability to personalized heat strain monitoring.

Postoperative hypothermia is associated with reduced length of stay in adult acute burn survivors.

BACKGROUND: The hypermetabolic response after a burn predisposes patients to hypothermia due to dysfunction of thermoregulation. Traditionally, hypothermia is avoided actively in burn care due to reported complications associated with low body temperature. The likelihood of hypothermia with acute burn surgery is compounded by general anesthesia, exposure of wound areas and prolonged operation times. However, we find limited studies exploring the effects of perioperative hypothermia on length of stay in the adult burn population. OBJECTIVE: To determine associations between postoperative hypothermia and hospital length of stay in adult burns patients. METHOD: This retrospective cohort study involved patients admitted to the State Adult Burn Unit in Western Australia between 1st January 2015 to 28th February 2021. All adults who underwent surgery for acute burn, and had postoperative recovery room body temperature recorded, were included in the study. In this study, we defined normothermia as >36.5C and hypothermia as < 36.0 °C with mild, moderate, and severe hypothermia being 35.0-35.9 °C, 34.0-34.9 °C and < 34.0 °C, respectively. Patients with hyperthermia were excluded. Multivariable general linear models explored if hypothermia was independently associated with length of stay. RESULTS: Among 1486 adult patients, 1338 (90%) were normothermic postoperatively, with temperatures >36.0C. We included 148 (10%) patients with hypothermia (temperature <36.0 °C) postoperatively. Most burns in the study population were minor: 96% had burns < 15% TBSA. Data modelling demonstrated that hypothermia was associated with a shorter length of hospital stay (coefficient = -0.129, p = 0.041). CONCLUSION: In adult acute burn patients, postoperative hypothermia was associated with reduced length of stay after surgery. The positive results of this study indicate that a review of the core temperature targets with acute burn surgery, and timing of burn patient cooling practices in general is warranted.

Mice with deficiency in Pcdh15, a gene associated with bipolar disorders, exhibit significantly elevated diurnal amplitudes of locomotion and body temperature.

Genetic factors significantly affect the pathogenesis of psychiatric disorders. However, the specific pathogenic mechanisms underlying these effects are not fully understood. Recent extensive genomic studies have implicated the protocadherin-related 15 (PCDH15) gene in the onset of psychiatric disorders, such as bipolar disorder (BD). To further investigate the pathogenesis of these psychiatric disorders, we developed a mouse model lacking Pcdh15. Notably, although PCDH15 is primarily identified as the causative gene of Usher syndrome, which presents with visual and auditory impairments, our mice with Pcdh15 homozygous deletion (Pcdh15-null) did not exhibit observable structural abnormalities in either the retina or the inner ear. The Pcdh15-null mice showed very high levels of spontaneous motor activity which was too disturbed to perform standard behavioral testing. However, the Pcdh15 heterozygous deletion mice (Pcdh15-het) exhibited enhanced spontaneous locomotor activity, reduced prepulse inhibition, and diminished cliff avoidance behavior. These observations agreed with the symptoms observed in patients with various psychiatric disorders and several mouse models of psychiatric diseases. Specifically, the hyperactivity may mirror the manic episodes in BD. To obtain a more physiological, long-term quantification of the hyperactive phenotype, we implanted nano tag® sensor chips in the animals, to enable the continuous monitoring of both activity and body temperature. During the light-off period, Pcdh15-null exhibited elevated activity and body temperature compared with wild-type (WT) mice. However, we observed a decreased body temperature during the light-on period. Comprehensive brain activity was visualized using c-Fos mapping, which was assessed during the activity and temperature peak and trough. There was a stark contrast between the distribution of c-Fos expression in Pcdh15-null and WT brains during both the light-on and light-off periods. These results provide valuable insights into the neural basis of the behavioral and thermal characteristics of Pcdh15-deletion mice. Therefore, Pcdh15-deletion mice can be a novel model for BD with mania and other psychiatric disorders, with a strong genetic component that satisfies both construct and surface validity.

Hypothermia as potential therapeutic approach to attenuating soman-induced seizure, neuropathology, and mortality with an adenosine A1 receptor agonist and body cooling.

Organophosphorus nerve agents, such as soman (GD), produce excitotoxic effects resulting in sustained status epilepticus (SSE) and brain damage. Previous work shows that neuronal inhibitory effects of A1 adenosine receptor (A1AR) agonists, such as N6- Bicyclo (2.2.1)-hept-2-yl-5'-chloro-5'-deoxyadenosine (Cl-ENBA), suppresses GD-induced SSE and improves neuropathology. Some other physiologic effects of these agonists are hypothermia, hypotension, and sedation. Hypothermia may also shield the brain from injury by slowing down chemical insults, lessening inflammation, and contributing to improved neurological outcomes. Therefore, we attempted to isolate the hypothermic effect from ENBA by assessing the neuroprotective efficacy of direct surface body cooling in a rat GD-induced SSE model, and comparing the effects on seizure termination, neuropathology, and survival. Male rats implanted with a body temperature (Tb) transponder and electroencephalographic (EEG) electrodes were primed with asoxime (HI-6), exposed to GD 30 min later, and then treated with Cl-ENBA or had Tb lowered directly via body cooling at 30 min after the onset of seizure activity. Afterwards, they were either allowed to develop hypothermia as expected, or received thermal support to maintain normothermic Tb for a period of 6-h. Neuropathology was assessed at 24 h. Regardless of Cl-ENBA or surface cooling, all hypothermic GD-exposed groups had significantly improved 24-h survival compared to rats with normothermic Tb (81% vs. 39%, p < 0.001). Cl-ENBA offered neuroprotection independently of hypothermic Tb. While hypothermia enhanced the overall efficacy of Cl-ENBA by improving survival outcomes, body cooling didn't reduce seizure activity or neuropathology following GD-induced SSE.

Impact of intraoperative hypothermia on the recovery period of anesthesia in elderly patients undergoing abdominal surgery.

BACKGROUND: This study aimed to investigate the impact of intraoperative hypothermia on the recovery period of anesthesia in elderly patients undergoing abdominal surgery. METHODS: A prospective observational study was conducted based on inclusion and exclusion criteria. A total of 384 elderly patients undergoing abdominal surgery under general anesthesia were enrolled in a grade A tertiary hospital in Chengdu, Sichuan Province from October 2021 and October 2022. After anesthesia induction, inflatable warming blankets were routinely used for active heat preservation, and nasopharyngeal temperature was monitored to observe the occurrence of intraoperative hypothermia. Patients were divided into hypothermia group and nonhypothermia group according to whether hypothermia occurred during the operation. Anesthesia recovery time and the incidence of adverse events or unwanted events during anesthesia recovery between the two groups were compared. RESULTS: The numbers (percentage) of 384 patients who underwent abdominal surgery developed intraoperative hypothermia occurred in 240 (62.5%) patients, all of whom had mild hypothermia. There were statistically significant differences between mild hypothermia after active warming and nonhypothermia in the occurrence of shivering (χ2 = 5.197, P = 0.023) and anesthesia recovery time (Z = -2.269, P = 0.02) in elderly patients undergoing abdominal surgery during anesthesia recovery, and there were no statistically significant differences in hypoxemia, nausea or vomiting, hypertension, hypokalemia, hypocalcemia, analgesic drug use,postoperative wound infection or postoperative hospitalization days. CONCLUSIONS: The incidence of intraoperative mild hypothermia after active warming was high in elderly patients who underwent abdominal surgery. Mild hypothermia increased the incidence of shivering and prolonged anesthesia recovery time in elderly patients undergoing abdominal surgery.

Average Temperature as a Marker of Lymphoma-Associated HLH.

METHODS: This retrospective analysis aimed to assess whether a 12-hour mean temperature (measured around either diagnosis of HLH or peak ferritin value) has value as a quick and simple diagnostic test for HLH in people with lymphoproliferative disease (LPD). Hospital records from 2018 to 2022 were retrospectively screened for patients with LPD and peak ferritin during admission to hospital >3000ng/mL. Patients were grouped as either HLH or non-HLH after consensus discussion at a multi-disciplinary meeting with access to full, detailed patient records and H-scores. RESULTS: The total cohort of 23 patients consisted of 12 with HLH and 11 grouped as non-HLH. 12-hour mean temperature at HLH diagnosis was 38.6 °C in the HLH cohort and 37.5 °C measured at the point of peak ferritin measurement in non-HLH groups. It was also positively correlated with HLH status (P = 0.001) and showed high retrospective sensitivity and specificity for HLH above 37.7 °C. CONCLUSION: These results demonstrate that a 12-hour mean temperature may add value and diagnostic certainty to the first-line investigations for HLH associated with LPD. The moderately high sensitivity and specificity achieved with this dataset supports the need for further research into whether the test retains validity in larger patient groups.

Pressure injury risk factors in patients undergoing general anesthesia surgeries.

BACKGROUND: Pressure injuries result from prolonged pressure and lead to tissue damage, infections, extended recovery times, and an economic burden. PURPOSE: To explore risk factors for pressure injuries in patients who underwent surgery under general anesthesia. METHODS: This retrospective study included patients who underwent surgery at a regional educational hospital in southern Taiwan from January 1, 2018, through December 31, 2018. RESULTS: A comprehensive multivariate analysis was used to identify the prominent risk factors for pressure injury among the 11 231 patients enrolled in this study. These risk factors were an age of ≥65 years; surgery duration of >120 minutes; diastolic blood pressure of <60 mm Hg for >30 minutes during surgery; intraoperative use of dopamine, norepinephrine, or epinephrine as vasopressors; American Society of Anesthesiologists physical classification of III or higher; minimum intraoperative body temperature of ≤35°C; blood loss of >500 mL; and a supine or prone surgical position. CONCLUSIONS: This study identified several pressure injury risk factors related to surgical conditions and patient characteristics. Surgical teams must monitor, control, and manage these factors, prioritize staff education, and adopt preventive protocols.

Kaempferol 3-O-Rutinoside, a Flavone Derived from Tetrastigma hemsleyanum Diels et Gilg, Reduces Body Temperature through Accelerating the Elimination of IL-6 and TNF-α in a Mouse Fever Model.

Fever is a serious condition that can lead to various consequences ranging from prolonged illness to death. Tetrastigma hemsleyanum Diels et Gilg (T. hemsleyanum) has been used for centuries to treat fever, but the specific chemicals responsible for its antipyretic effects are not well understood. This study aimed to isolate and identify the chemicals with antipyretic bioactivity in T. hemsleyanum extracts and to provide an explanation for the use of T. hemsleyanum as a Chinese herbal medicine for fever treatment. Our results demonstrate that kaempferol 3-rutinoside (K3OR) could be successfully isolated and purified from the roots of T. hemsleyanum. Furthermore, K3OR exhibited a significant reduction in rectal temperature in a mouse model of fever. Notably, a 4 µM concentration of K3OR showed more effective antipyretic effects than ibuprofen and acetaminophen. To explore the underlying mechanism, we conducted an RNA sequencing analysis, which revealed that PXN may act as a key regulator in the fever process induced by lipopolysaccharide (LPS). In the mouse model of fever, K3OR significantly promoted the secretion of IL-6 and TNF-α during the early stage in the LPS-treated group. However, during the middle to late stages, K3OR facilitated the elimination of IL-6 and TNF-α in the LPS-treated group. Overall, our study successfully identified the chemicals responsible for the antipyretic bioactivity in T. hemsleyanum extracts, and it answered the question as to why T. hemsleyanum is used as a traditional Chinese herbal medicine for treating fever. These findings contribute to a better understanding of the therapeutic potential of T. hemsleyanum in managing fever, and they provide a basis for further research and development in this field.

Evaluation of different body temperature measurement methods for patients in the intraoperative period.

OBJECTIVES: this study aimed at estimating and comparing the reliability of temperature measurements obtained using a peripheral infrared temporal thermometer, a central cutaneous thermometer ("Zero-Heat-Flux Cutaneous thermometer") and an esophageal or nasopharyngeal thermometer among elective surgical patients in the intraoperative period. METHOD: a longitudinal study with repeated measures carried out by convenience sampling of 99 patients, aged at least 18 years old, undergoing elective abdominal cancer surgeries, with anesthesia lasting at least one hour, with each patient having their temperature measured by all three methods. RESULTS: the intraclass correlation coefficient showed a low correlation between the measurements using the peripheral temporal thermometer and the central cutaneous (0.0324) and esophageal/nasopharyngeal (-0.138) thermometers. There was a high correlation (0.744) between the central thermometers evaluated. CONCLUSION: the data from the current study do not recommend using infrared temporal thermometers as a strategy for measuring the body temperature of patients undergoing anesthetic-surgical procedures. Central cutaneous thermometers and esophageal/nasopharyngeal thermometers are equivalent for detecting intraoperative hypothermia.

Evaluation of Conditions for the Development of Cryogenic Spinal Cord Injury Using a Canine Model: An Experimental Study on the Safety of Cryoablation for Metastatic Spinal Tumors.

BACKGROUND AND PURPOSE: Although the application of cryoablation to metastatic spinal tumors has been attempted, spinal cryoablation has the unique complication of cryogenic spinal cord injury. This study aimed to elucidate the conditions for the development of cryogenic spinal cord injury. MATERIALS AND METHODS: Fifteen canines were used in this study. A metal probe was inserted into the 13th thoracic vertebral body. Cryoablation was performed for 10 minutes by freezing the probe in liquid nitrogen. The control canine underwent probe insertion only. Spinal cord monitoring, epidural temperature measurement, motor function assessment, and pathologic examination of the spinal cord were performed. RESULTS: During the 10 minutes of cryoablation, the epidural temperature decreased and reached the lowest epidural temperature (LET) at the end of cryoablation. The LETs (degrees celsius [°C]) of each canine were -37, -30, -27, -8, -3, -2, 0, 1, 4, 8, 16, 18, 20, and 25, respectively. As the epidural temperature decreased, waveform amplitudes also decreased. At the end of cryoablation (10 minutes after the start of cryoablation), abnormal waves were observed in 92.9% (13/14) of canines. With epidural rewarming, the amplitude of the waveforms tended to recover. After epidural rewarming (2 hours after the start of cryoablation), abnormal waves were observed in 28.6% (4/14) of canines. The LETs (°C) of the canines with abnormal waves after epidural rewarming were -37, -30, -27, and -8. None of the canines with normal waves after epidural rewarming had any motor impairment. In contrast, all canines with remaining abnormal waves after epidural rewarming had motor impairment. In the pathologic assessment, cryogenic changes were found in canines with LETs (°C) of -37 -30, -27, -8, 0, and 1. CONCLUSIONS: This study showed that 10-minute spinal cryoablation with LETs (°C) of -37, -30, -27, -8, 0, and 1 caused cryogenic spinal cord injury. There was no evidence of cryogenic spinal cord injury in canines with LET of ≥4°C. The epidural temperature threshold for cryogenic spinal cord injury is between 1 and 4°C, suggesting that the epidural temperature should be maintained above at least 4°C to prevent cryogenic spinal cord injury.

Quantitative and comparative analysis of thermography parameters in posterior scleritis, choroiditis, and controls.

PURPOSE: To compare various ocular thermography parameters in posterior scleritis (PS), choroiditis (choroidal granuloma [CG], Vogt-Koyanagi-Harada [VKH] syndrome), central serous chorioretinopathy (CSCR), and healthy controls. METHODS: This retrospective, observational, comparative study evaluated cases undergoing ocular thermography between April 2017 and October 2023. The study groups included cases of PS, CG, and VKH, while the control group comprised CSCR cases and healthy individuals. Various thermography parameters were assessed, which were as follows: Ocular surface temperature (OST), central corneal temperature (CCT), average scleral temperature (ST), nasal scleral temperature (nST), temperature difference between both the eyes (∆t), and difference between scleral and corneal temperatures (ST - CCT, nST - CCT). RESULTS: It was found that ∆t was significantly higher in the PS group compared to the CG ( P = 0.005), CSCR ( P = 0.0001), and control groups (dilated control: P =0.006, undilated control: P = 0.0001). ST - CCT and nST - CCT were significantly higher in the undilated control and CSCR groups and significantly lower in the PS group. ST - CCT and nST - CCT showed less difference in the affected eyes compared to contralateral healthy eyes of PS and CG cases. OST, CCT, ST, and nST displayed statistically insignificant differences across all groups. CONCLUSION: It is advisable to focus on temperature differences between the affected and healthy eyes, or the difference between the central corneal and scleral temperature of the affected eye, utilizing parameters such as ∆t, ST - CCT, and nST - CCT. These composite parameters offer a more effective approach than individual measurements like OST, CCT, ST, and nST. Thermography can serve as a screening tool to suspect and differentiate PS.

Evaluation of Thermal Support during Anesthesia Induction on Body Temperature in C57BL/6 and Nude Mice.

Heat supplementation during surgery is a common practice; however, thermal support is not commonly used during anesthesia induction. Mice lose body temperature quickly, and air movement can exacerbate this, potentially putting mice at a thermal deficit before surgery. Whether the method of warming during induction affects overall heat loss during anesthesia is unknown. We hypothesized that the method of heating would affect body temperature (Tb) during anesthesia induction, maintenance, recovery, and once placed back on the rack. Mice (C57BL/6NHsd-6M/6F [C57BL/6]; Hsd:Athymic Nude-Foxn1nu [Nude]; N = 24;12M/12F) were assigned to a treatment in a factorial design: thermal chamber (TC; ambient temperature [Ta] = 28.8°C); heating pad (HP; induction chamber placed on an electric heating pad;Ta = 28.4°C); and control (Ctrl; Ta = 21.6°C). During induction, one mouse at a time was anesthetized with isoflurane over a 3min period and then maintained under anesthesia for 10min on a hot water heating pad (33 °C). Then isoflurane was stopped and time to ambulation was recorded. Tb and activity were tracked in the home cage on the rack before and after anesthesia. During induction, Ctrl mice lost significantly more heat (-2.8 °C) than did TC (+0.2 °C) and HP mice (+0.1 °C) but TC and HP were not different. During anesthesia maintenance, Ctrl mice regained 1 °C, but their Tb was still lower than that of the treated groups. Nude mice consistently had a lower Tb than C57BL/6 mice, regardless of treatment or anesthesia phase. C57BL/6 Ctrl mice took longer to ambulate than either HP or TC mice, but the method of heating did not differentially affect Nude mice. In general, C57BL/6 as compared with Nude and females as compared with males were comparatively more active and had higher Tb during certain times of day, regardless of the heating methods. Overall, our findings support the provision of heat during anesthesia induction, regardless of method, to reduce overall Tb loss during a short anesthesia event.

Factors Influencing the Occurrence of Intraoperative Hypothermia in Patients Undergoing General Anesthesia Intervention: A Study in a Tertiary Care Hospital.

BACKGROUND Intraoperative and postoperative hypothermia of patients can be caused by the use of anesthetic drugs and the complicated and time-consuming procedures of interventional surgery. This retrospective study included 184 patients to investigate the incidence and factors associated with hypothermia during intraoperative anesthesia in a single center in China between January and October 2023. MATERIAL AND METHODS A convenient sampling method was used to select 184 patients who underwent general anesthesia intervention in a tertiary hospital in Sichuan Province from January to October 2023 as the study population. The independent factors influencing the occurrence of intraoperative hypothermia were analyzed. A survey was conducted to collect 5 demographic factors, 4 preoperative-related factors, and 10 surgically related factors. According to the occurrence of intraoperative hypothermia, the independent influencing factors of unplanned hypothermia during perioperative period were further analyzed. RESULTS Among 184 patients, 64 (34.78%) experienced perioperative unplanned hypothermia, of which 5 (7.81%) cases occurred before the start of surgery, 7 (10.94%) occurred before the start of surgery after anesthesia, and 52 (81.25%) occurred during surgery. Logistic regression analysis showed that body temperature at the beginning of surgery (P<0.001), set operating room temperature (P<0.001), duration of anesthesia (P=0.006), and age (P=0.001) were independent influencing factors for unplanned hypothermia during perioperative period. CONCLUSIONS The incidence of intraoperative hypothermia is high in patients undergoing general anesthesia interventions. Age, duration of anesthesia, set operating room temperature, and body temperature at the beginning of the operation were independent influencing factors for the occurrence of unplanned hypothermia during the perioperative period.