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The impact of the location where accidental hypothermia (AH) occurs has not been fully investigated thus far. This was a multicenter retrospective study of patients with a body temperature ≤35°C obtained at the emergency department of 12 hospitals in Japan between April 2011 and March 2016. We divided the patients into two groups according to the location where AH occurred (indoor group versus outdoor group). The association between each location of the occurrence of AH and in-hospital mortality was evaluated via a multivariable logistic regression analysis. The primary outcome of this study was in-hospital death. The secondary outcomes were the lengths of ICU and hospital stay. A total of 572 patients were enrolled in the hypothermia database, and 537 patients were included in the analyses. A total of 119 and 418 patients experienced hypothermia with outdoor and indoor occurrence, respectively. The indoor group was older and had worse activities of daily living compared with the outdoor group. With regard to the outcome, the proportion of in-hospital death was higher in the indoor group than in the outdoor group (28.2% [118/418] vs. 10.9% [13/119]

Background: Severe accidental hypothermia (AH) is a life-threatening condition, and early identification can enable transport to an appropriate medical facility. The Swiss staging model has been used to classify patients with AH, but little is known regarding the relationship between the degree of impaired consciousness and core body temperature (BT) in AH. This study aimed to clarify the relationship between the level of consciousness and core BT and determine whether the level of consciousness could be used to predict severe hypothermia and in-hospital mortality among patients with AH.Methods: We retrospectively investigated the clinical relevance of impaired consciousness in AH. We included adult patients with AH and excluded patients with out-of-hospital cardiac arrest. The patients were identified from the J-point registry, which contains information regarding patients treated for AH between April 1, 2011 and March 31, 2016 in any of the 12 participating institutions in Japan. The primary exposure of interest was the level of consciousness at hospital arrival. Odds ratios were calculated for severe hypothermia and in-hospital mortality.Results: Overall, 505 of the 572 patients in the registry were included. Compared to mildly impaired consciousness, the adjusted odds ratio for severe hypothermia was 3.3 (95% confidence interval [CI]: 1.7–6.3) for moderately impaired consciousness and 4.7 (95% CI: 2.4–9.1) for severely impaired consciousness. Severely impaired consciousness as a predictor severe hypothermia had a sensitivity of 0.44 (95% CI: 0.34–0.54), specificity of 0.78 (95% CI: 0.74–0.82), positive likelihood ratio of 2.04, and negative likelihood ratio of 0.71. Compared to mildly impaired consciousness, the adjusted odds ratio for in-hospital mortality was 1.7 (95% CI: 0.95–2.9) for moderately impaired consciousness and 2.1 (95% CI: 1.2–3.8) for severely impaired consciousness.Conclusions: Severely impaired consciousness was a reliable predictor of severe hypothermia and in-hospital mortality in patients with AH. Thus, in an urban out-of-hospital emergency setting, the level of impaired consciousness may be helpful for triaging patients to the appropriate hospital.

Nobunaga Okada, Tasuku Matsuyama, Sachiko Morita, Naoki Ehara, Nobuhiro Miyamae, Yohei Okada, Takaaki Jo, Yasuyuki Sumida, Makoto Watanabe, Masahiro Nozawa, Ayumu Tsuruoka, Yoshihiro Fujimoto, Yoshiki Okumura, Kunio Hamanaka, Tetsuhisa Kitamura, Kei Nishiyama, Bon Ohta, Osborn Wave Is Related to Ventricular Fibrillation and Tachycardia in Hypothermic Patients, Circulation Journal, 2020, Volume 84, Issue 3, Pages 445-455, Released February 25, 2020, [Advance publication] Released January 30, 2020, Online ISSN 1347-4820, Print ISSN 1346-9843, https://doi.org/10.1253/circj.CJ-19-0856, https://www.jstage.jst.go.jp/article/circj/84/3/84_CJ-19-0856/_article/-char/en, BACKGROUND: The Osborn wave (OW) is often observed in hypothermic patients; however, whether OW in hypothermic patients is related to the development of fatal ventricular arrhythmia, including ventricular fibrillation (VF) and pulseless ventricular tachycardia (VT), remains undetermined. This study aimed to estimate the association between OW and the incidence of fatal ventricular arrhythmias.Methods and Results: This retrospective study used the Japanese Accidental Hypothermia Network registry database and included 572 hypothermic patients. Patients were divided into the OW group (those with OW) and non-OW group (those without OW). The relationship between the development of fatal arrhythmias and presence of OW was assessed using the chi-squared test. All patients who developed VF/VT (n=10) had OW on electrocardiogram upon hospital arrival. The presence of OW had a sensitivity of 100%, specificity of 47.8%, positive predictive value of 4.0%, and negative predictive value of 100% for VF/VT development. The in-hospital mortality rate was 22.3% in the OW group and 21.2% in the non-OW group (P=0.781). CONCLUSIONS: OW was observed in all hypothermic patients with VF/VT. The occurrence of ventricular arrhythmias is highly unlikely in the absence of OW on the electrocardiogram. Although the presence of OW might be used to predict these fatal arrhythmias in hypothermic patients, there was no association between the presence of OW and in-hospital mortality.

Kandori, K., Okada, Y., Matsuyama, T. et al. Prognostic ability of the sequential organ failure assessment score in accidental hypothermia: a multi-institutional retrospective cohort study. Scand J Trauma Resusc Emerg Med 27, 103 (2019). https://doi.org/10.1186/s13049-019-0681-8, Background: Severe accidental hypothermia (AH) is life threatening. Thus, prognostic prediction in AH is essential to rapidly initiate intensive care. Several studies on prognostic factors for AH are known, but none have been established. We clarified the prognostic ability of the Sequential Organ Failure Assessment (SOFA) score in comparison with previously reported prognostic factors among patients with AH. Methods: The J-point registry database is a multi-institutional retrospective cohort study for AH in 12 Japanese emergency departments. From this registry, we enrolled patients who were treated at the intensive care unit (ICU) in various critical care medical centers. In-hospital mortality was the primary outcome. We investigated the discrimination ability of each candidate prognostic factor and the in-hospital mortality by applying the logistic regression models with areas under the receiver operating characteristic curve (AUROC) with 95% confidence interval (CI). Results: Of the 572 patients with AH registered in the J-point registry, 220 were eligible for the analyses. The in-hospital mortality was 23.2%. The AUROC of the SOFA score (0.80; 95% CI: 0.72-0.86) was the highest among all factors. The other factors were serum potassium (0.65; 95% CI: 0.55-0.73), lactate (0.67; 95% CI: 0.57-0.75), quick SOFA (qSOFA) (0.55; 95% CI: 0.46-0.65), systemic inflammatory response syndrome (SIRS) (0.60; 95% CI: 0.50-0.69), and 5A severity scale (0.77; 95% CI: 0.68-0.84). Discussion: Although serum potassium and lactate had relatively good discrimination ability as mortality predictors, the SOFA score had slightly better discrimination ability. The reason is that lactate and serum potassium were mainly reflected by the hemodynamic state; conversely, the SOFA score is a comprehensive score of organ failure, basing on six different scores from the respiratory, cardiovascular, hepatic, coagulation, renal, and neurological systems. Meanwhile, the qSOFA and SIRS scores underestimated the severity, with low discrimination abilities for mortality. Conclusions: The SOFA score demonstrated better discrimination ability as a mortality predictor among all known prognostic factors in patients with AH.

In order to reduce infection risk of novel coronavirus (SARS-CoV-2), we developed photocatalysts with nanoscale rutile TiO2 (4–8 nm) and CuxO (1–2 nm or less). Their extraordinarily small size leads to high dispersity and good optical transparency, besides large active surface area. Those photocatalysts can be applied to white and translucent latex paints and a transparent varnish. Although Cu2O clusters involved in the paint coating undergo gradual aerobic oxidation in the dark, the oxidized clusters are re-reduced under >380 nm light. The paint coating inactivated novel coronavirus and its alpha (B.1.1.7) variant under irradiation with fluorescent light for 3 h. The coating also exhibited antivirus effects on influenza A virus, feline calicivirus and bacteriophage Qβ. The photocatalysts would be applied to practical coatings and lower the risk of coronavirus infection via solid surfaces.

Okada, Y., Matsuyama, T., Morita, S., et al. Machine learning-based prediction models for accidental hypothermia patients. j intensive care 9, 6 (2021). https://doi.org/10.1186/s40560-021-00525-z, Background: Accidental hypothermia is a critical condition with high risks of fatal arrhythmia, multiple organ failure, and mortality; however, there is no established model to predict the mortality. The present study aimed to develop and validate machine learning-based models for predicting in-hospital mortality using easily available data at hospital admission among the patients with accidental hypothermia. Method: This study was secondary analysis of multi-center retrospective cohort study (J-point registry) including patients with accidental hypothermia. Adult patients with body temperature 35.0 °C or less at emergency department were included. Prediction models for in-hospital mortality using machine learning (lasso, random forest, and gradient boosting tree) were made in development cohort from six hospitals, and the predictive performance were assessed in validation cohort from other six hospitals. As a reference, we compared the SOFA score and 5A score. Results: We included total 532 patients in the development cohort [N = 288, six hospitals, in-hospital mortality: 22.0% (64/288)], and the validation cohort [N = 244, six hospitals, in-hospital mortality 27.0% (66/244)]. The C-statistics [95% CI] of the models in validation cohorts were as follows: lasso 0.784 [0.717-0.851] , random forest 0.794[0.735-0.853], gradient boosting tree 0.780 [0.714-0.847], SOFA 0.787 [0.722-0.851], and 5A score 0.750[0.681-0.820]. The calibration plot showed that these models were well calibrated to observed in-hospital mortality. Decision curve analysis indicated that these models obtained clinical net-benefit. Conclusion: This multi-center retrospective cohort study indicated that machine learning-based prediction models could accurately predict in-hospital mortality in validation cohort among the accidental hypothermia patients. These models might be able to support physicians and patient’s decision-making. However, the applicability to clinical settings, and the actual clinical utility is still unclear; thus, further prospective study is warranted to evaluate the clinical usefulness.

Care at a critical care medical center is associated with improved outcomes in patients with accidental hypothermia. In subgroup analyses, shock was associated with poor outcomes of accidental hypothermia. Optimizing the transport of patients with accidental hypothermia to a specialized center is likely to be beneficial., Aim The recommendation that patients with accidental hypothermia should be transported to specialized centers that can provide extracorporeal life support has not been validated, and the efficacy remains unclear. Methods This was a multicenter retrospective cohort study of patients with a body temperature of ≤35°C presenting at the emergency department of 12 hospitals in Japan between April 2011 and March 2016. We divided the patients into two groups based on the point of care delivery: critical care medical center (CCMC) or non‐CCMC. The primary outcome of this study was in‐hospital death. In‐hospital death was compared using a multivariable logistic regression analysis. Subgroup analyses were carried out according to patients with severe hypothermia (

AIM We aimed to evaluate the prevalence and outcomes of accidental hypothermia (AH) among elderly patients in Japan. METHODS This was a multicenter chart review study of patients with AH (Japanese accidental hypothermia network registry; J-Point registry) that included patients with a body temperature ≤35 °C and those aged ≥18 years who visited the emergency department of 12 institutions in Japan from 1 April 2011 to 31 March 2016. The patients were classified into three groups: adult (aged 18-64 years), young-old (aged 65-79 years) and old-old (aged ≥80 years). The association between each age category and in-hospital mortality from AH was examined through a multivariable logistic regression analysis. RESULTS In total, 572 patients were registered in the J-Point registry database, of which 537 were included. The proportion of individuals who developed AH in an indoor setting was higher in the old-old group than in the adult group (86.9% [226/260] vs 61.1% [87/113]). The in-hospital mortality rates of the adult, young-old and old-old groups were 15.0% (17/113), 21.3% (35/164) and 30.4% (79/260), respectively. In the multivariable analysis, the in-hospital mortality rate was higher in the young-old and old-old groups than in the adult group (young-old vs adult, adjusted odds ratio: 2.31 and 95% confidence interval 1.16-4.64; old-old vs adult, adjusted odds ratio: 2.91 and 95% confidence interval 1.41-6.02). CONCLUSIONS Approximately 80% of patients with AH were aged ≥65 years. The in-hospital mortality rate of patients aged ≥65 years was significantly higher than that of those aged

Background Resuscitative endovascular balloon occlusion of the aorta (REBOA), which has been increasingly used for the management of hemorrhagic shock, is a less invasive strategy for the management of patients with very severe hemorrhage. However, its effectiveness remains controversial. Methods This retrospective case series included trauma patients who underwent REBOA for hemorrhagic shock due to trauma in four Japanese tertiary care emergency centers from January 2013 to March 2017. Patients in cardiac arrest at the time of REBOA and those who underwent REBOA for nontraumatic causes during the study period were excluded. Results A total of 24 patients underwent REBOA during the study period. The median age was 52 years (interquartile range (IQR) 36.5–62.5), 17 (70.8%) of the patients were male, and 23 (95.8%) had blunt trauma. The 24-h survival was 50% (n = 12), and the in-hospital survival rate was 41.7% (10/24). In all cases, REBOA was performed in emergency rooms by emergency physicians without fluoroscopic guidance. Complications of REBOA were mesenteric ischemia (n = 1, 4.2%), ischemia of the lower extremities (n = 1, 4.2%), and placement of REBOA in thoracic aortic injury (n = 3, 12.5%). Conclusions REBOA can be an effective and feasible tool for controlling massive hemorrhage due to trauma. However, caution should be exercised regarding complications including placement of REBOA in aortic injury and limb ischemia in cases where REBOA is performed in an emergency department setting with minimal or no support from trauma surgeons.

Background: Accidental hypothermia is a serious condition that requires immediate and accurate assessment to determine severity and treatment. Currently, accidental hypothermia is evaluated using the Swiss grading system which uses core body temperature and clinical findings; however, research has shown that core body temperature is not associated with in-hospital mortality in urban settings. Therefore, we developed and validated a severity scale for predicting in-hospital mortality among urban Japanese patients with accidental hypothermia. Methods: Data for this multi-center retrospective cohort study were obtained from the J-point registry. We included patients with accidental hypothermia who were admitted to an emergency department. The total cohort was divided into a development cohort and validation cohort, based on the location of each institution. We developed a logistic regression model for predicting in-hospital mortality using the development cohort and assessed its internal validity using bootstrapping. The model was then subjected to external validation using the validation cohorts. Conclusion: Our “5A” severity scoring system could accurately predict the risk of in-hospital mortality among patients with accidental hypothermia., The Correction to this article has been published in Journal of Intensive Care 2019 7:34, The Publisher Correction to this article has been published in Journal of Intensive Care 2019 7:43

Introduction In cases of severe accidental hypothermia (AH) in urban areas, the prognostic factors are unknown. We identified factors associated with in-hospital mortality in patients with moderate-to-severe AH in urban areas of Japan. Method The J-Point registry database is a multi-institutional retrospective cohort study for AH in 12 Japanese emergency departments. From this registry, we enrolled patients whose core body temperature was 32 °C or less on admission. In-hospital death was the primary outcome of this study. We investigated the association between each candidate prognostic factor and in-hospital death by applying the multivariate logistic regression analyses with adjusted odds ratios (AORs) and their 95% confidence interval [CI] as the effect variables. Results Of 572 patients registered in the J-point registry, 358 hypothermic patients were eligible for analyses. Median body temperature was 29.2 °C (interquartile range, 27.0 °C–30.8 °C). In-hospital deaths comprised 26.3% (94/358) of all study patients. Factors associated with in-hospital death were age ≥ 75 years (AOR, 3.09; 95% CI, 1.31–7.27), need for assistance with activities of daily living (ADL; AOR, 3.06; 95% CI, 1.68–5.59), hemodynamic instability (AOR, 2.49; 95% CI, 1.32–4.68), and hyperkalemia (≥5.6 mEq/L; AOR, 2.65; 95% CI, 1.13–6.21). Conclusion The independent prognostic factors associated with in-hospital mortality of patients with moderate-to-severe AH in urban areas of Japan were age ≥ 75 years, need for assistance with ADL, hemodynamic instability, and hyperkalemia.

Icosahedral Au@Ag core−shell nanocrystals have been prepared using a two-step reduction method. In the first step, icosahedral Au core seeds were prepared by reducing HAuCl4·4H2O in tetraethylene glycol (TEG) under microwave (MW) heating in the presence of polyvinylpyrrolidone (PVP) as a polymer surfactant. In the second step, Ag shells were overgrown on icosahedral Au seeds in N,N-dimethylformamide (DMF) in the presence of PVP under oil-bath heating for 3 h or MW heating for 10 min. Crystal structures of products were characterized using TEM, TEM-EDS, and SEM. Under oil-bath heating, Au@Ag icosahedral nanocrystals nearly fully covered by Ag shells were prepared, whereas those partially covered by tetrahedral units of Ag shells were formed under MW heating. On the basis of these findings, it was concluded that icosahedral Au@Ag core−shell particles are formed through stepwise growth of tetrahedral units, as observed in the crystal growth of monometallic icosahedral Ag crystals in DMF. There were minor Au/...

Accidental hypothermia (AH) has higher incidence and mortality in geriatric populations. Japan has a rapidly ageing population, and little is known about the epidemiology of hypothermia in this country.We created an AH registry based on retrospective review of patients visiting the ED of 12 institutions with temperature ≤35°C between April 2011 and March 2016. The severity of AH was classified as mild (≤35, ≥32°C), moderate (32, ≥28°C) or severe (28°C). The relationship between in-hospital mortality and severity of AH was assessed using a multivariable logistic regression analysis.A total of 572 patients were registered in this registry and 537 patients were eligible for our analysis. The median age was 79 (IQR 66-87) years and the proportion of men was 51.2% (273/537). AH was more likely to occur in elderly patients aged ≥65 years (424/537, 80.0%) and in indoor settings (418/537, 77.8%). The condition most frequently associated with AH, irrespective of severity, was acute medical illness. A lower mean outside temperature was associated with a higher prevalence of AH, and particularly severe AH (p for trend0.001). The overall proportion of cases resulting in in-hospital death was 24.4% (131/537), with no significant difference between severity levels observed in a multivariable logistic regression analysis (severe group (37/118, 31.4%) vs mild group (42/192, 21.9%), adjusted OR (AOR) 1.01, 95% CI 0.61 to 1.68; and moderate group (52/227, 22.9%) vs mild group, AOR 1.11, 95% CI 0.58 to 2.14).Active prevention and intervention should occur for this important public health issue.

Shape-dependent Au@Ag core−shell nanocrystals have been successfully synthesized by using a two-step method. First, Au nanocrystal seeds with various shapes including single-crystal octahedron, single-twinned triangle or hexagon plate, and multiple-twinned decahedron were prepared by reducing HAuCl4 in ethylene glycol (EG) in the presence of polyvinylpyrrolidone (PVP) as a polymer surfactant under the condition of microwave heating. Subsequently, thus-obtained Au seeds were added into N,N-dimethylformamide (DMF) solution containing Ag+ ions for overgrowth of Ag shells by an oil-bath heating. Transmission electron microscope (TEM) observation demonstrates that shapes of formed Ag shells strongly depend on shapes of initiated Au seeds. These newly produced triangular or hexagonal platelike, octahedral, and multiple-twinned decahedral Au@Ag nanocrystals are mainly dominated by the Ag shells having {111} facets. This case is completely different from that previously investigated by us in EG system where forme...

Roles of chloride ion in the formation of Au@Ag core–shell nanocrystal structures through a separated two-step process have been studied using a microwave (MW)-polyol method. The first step is to reduce HAuCl4 precursor to form Au cores and the second is to grow Ag shells epitaxially around the pre-existing Au nuclei by reducing AgNO3 at various Cl− concentrations. Without Cl− ions in the second step, dominant product is spherical Ag particles and few Au@Ag particles can be produced. While, higher Cl− ion concentrations lead to the formation of a significant amount of AgCl due to the reaction between Cl− from HAuCl4 or NaCl and Ag+ from AgNO3, which will remarkably interfere with the formation of Au@Ag nanocrystals. A small amount of Cl− anions (∼0.3 mM) has been found to be a key factor for the preferential formation of Au@Ag nanocrystals with well-defined shapes. The role of Cl− anions has been discussed in terms of shape selective oxidative etching of spherical Ag nanoparticles and the formation of AgCl leading to slow face-selective crystal growth by decreasing the concentration of free Ag+ ions. Under our MW heating condition, spherical Ag particles or shells are preferentially etched, while single crystal cubic, twinned bi-pyramidal, and five-twinned nano-rod/-wire structures can survive and further grow into larger particles or Au@Ag core–shell nanostructures with clear facets and shape edges. This finding provides new information in stability of twinned Au@Ag core–shell and Ag nanoparticles against oxidative etching by Cl−/O2 (dissolved in solvent).

Silver nanostructures have been synthesized by a microwave (MW)-polyol method. When AgNO3 was reduced by ethylene glycol (EG) in the presence of Pt seeds and polyvinylpyrrolidone (PVP), mixtures of one-dimensional (1-D) nanorods and nanowires, 2-D nanosheets and nanoplates, and 3-D spherical and cubic nanoparticles were prepared within a few minutes. It was found that morphologies and sizes of silver nanostructures depended strongly on such experimental parameters as concentrations of Pt, PVP, and AgNO3, and heating time. Possible growth mechanism of each silver nanostructure was discussed. The growth mechanism of nanorods was especially discussed on the basis of crystal structure of rod type of Au core-Ag shell nanoparticle.

Silver nanorods and nanowires have been synthesized by using a microwave (MW)-polyol method. When AgNO3 was reduced by ethylene glycol (EG) in the presence of Pt seeds and a long chain length of poly(vinylpyrrolidone) (PVP: Mw = 360 k), mixtures of one-dimensional (1-D) silver nanorods and nanowires and three-dimensional (3-D) spherical, triangular-bipyramidal, and cubic nanoparticles were synthesized within a few minutes. The average diameters, lengths, and yields of these products were measured as a function of concentration of Pt, PVP, or AgNO3, heating time, or MW power to determine optimum conditions for the synthesis of 1-D products. 1-D products could be easily separated from other 3-D nanoparticles by repeating centrifugal separation in water. Longer and thicker 1-D products could be prepared by using 1-D products as seeds and repeating the reduction of AgNO3 in EG under MW irradiation. In this two-step preparation, some bent 1-D wires due to the combination of {111} facets of two rods and wires ...

When silver nanostructures were prepared by a microwave(MW)-polyol method in the presence of polyvinylpyrrolidone (PVP) as a capping reagent, besides spherical nanoparticles, nanosheets, polygonal nanoplates, nanorods, and nanowires were synthesized within 8 min. Effects of chain length of PVP were examined by using three different molecular weights of PVPs (10, 40, and 360 k). When a short chain PVP (10 k) was used, nanosheets and nanoplates were dominantly prepared, while nanorods and nanowires were preferentially synthesized by using longer chain PVPs (40, 360 k). The maximum aspect ratios of nanorods and nanowires were ∼ 7, ∼ 130, and ∼ 200 for PVP (10, 40, 360 k), respectively. These results indicated that shape and size of Ag nanostructures can be controlled by changing chain length of PVP. On the basis of UV and visible absorption spectra of product solutions, the number density of Ag nanostructures including spherical nanoparticles increased rapidly with increasing chain length of PVP.