Personalised risk prediction following emergency department assessment for syncope.

BACKGROUND: Published risk tools do not provide possible management options for syncope in the emergency department (ED). Using the 30-day observed risk estimates based on the Canadian Syncope Risk Score (CSRS), we developed personalised risk prediction to guide management decisions. METHODS: We pooled previously reported data from two large cohort studies, the CSRS derivation and validation cohorts, that prospectively enrolled adults (≥16 years) with syncope at 11 Canadian EDs between 2010 and 2018. Using this larger cohort, we calculated the CSRS calibration and discrimination, and determined with greater precision than in previous studies the 30-day risk of adjudicated serious outcomes not identified during the index ED evaluation depending on the CSRS and the risk category. Based on these findings, we developed an on-line calculator and pictorial decision aids. RESULTS: 8233 patients were included of whom 295 (3.6%, 95% CI 3.2% to 4.0%) experienced 30-day serious outcomes. The calibration slope was 1.0, and the area under the curve was 0.88 (95% CI 0.87 to 0.91). The observed risk increased from 0.3% (95% CI 0.2% to 0.5%) in the very-low-risk group (CSRS -3 to -2) to 42.7% (95% CI 35.0% to 50.7%), in the very-high-risk (CSRS≥+6) group (Cochrane-Armitage trend test p<0.001). Among the very-low and low-risk patients (score -3 to 0), ≤1.0% had any serious outcome, there was one death due to sepsis and none suffered a ventricular arrhythmia. Among the medium-risk patients (score +1 to+3), 7.8% had serious outcomes, with <1% death, and a serious outcome was present in >20% of high/very-high-risk patients (score +4 to+11) including 4%-6% deaths. The online calculator and the pictorial aids can be found at: https://teamvenk.com/csrs CONCLUSIONS: 30-day observed risk estimates from a large cohort of patients can be obtained for management decision-making. Our work suggests very-low-risk and low-risk patients may be discharged, discussion with patients regarding investigations and disposition are needed for medium-risk patients, and high-risk patients should be hospitalised. The online calculator, accompanied by pictorial decision aids for the CSRS, may assist in discussion with patients.

Prospective validation of a clinical decision rule to identify patients presenting to the emergency department with chest pain who can safely be removed from cardiac monitoring.

BACKGROUND: Most patients with chest pain in the emergency department are assigned to cardiac monitoring for several hours, blocking access for patients in greater need. We sought to validate a previously derived decision rule for safe removal of patients from cardiac monitoring after initial evaluation in the emergency department. METHODS: We prospectively enrolled adults (age ≥ 18 yr) who presented with chest pain and were assigned to cardiac monitoring at 2 academic emergency departments over 18 months. We collected standardized baseline characteristics, findings from clinical evaluations and predictors for the Ottawa Chest Pain Cardiac Monitoring Rule: whether the patient is currently free of chest pain, and whether the electrocardiogram is normal or shows only nonspecific changes. The outcome was an arrhythmia requiring intervention in the emergency department or within 8 hours of presentation to the emergency department. We calculated diagnostic characteristics for the clinical prediction rule. RESULTS: We included 796 patients (mean age 63.8 yr, 55.8% male, 8.9% admitted to hospital). Fifteen patients (1.9%) had an arrhythmia, and the rule performed with the following characteristics: sensitivity 100% (95% confidence interval [CI] 78.2%-100%) and specificity 36.4% (95% CI 33.0%-39.6%). Application of the Ottawa Chest Pain Cardiac Monitoring Rule would have allowed 284 out of 796 patients (35.7%) to be safely removed from cardiac monitoring. INTERPRETATION: We successfully validated the decision rule for safe removal of a large subset of patients with chest pain from cardiac monitoring after initial evaluation in the emergency department. Implementation of this simple yet highly sensitive rule will allow for improved use of health care resources.

Improved High-Temperature Thermoelectric Properties of Dual-Doped Ca3Co4O9.

Layered structured Ca3Co4O9 has displayed great potential for thermoelectric (TE) renewable energy applications, as it is nontoxic and contains abundantly available constituent elements. In this work, we study the crystal structure and high-temperature TE properties of Ca3-2y Na2y Co4-y Mo y O9 (0 ≤ y ≤ 0.10) polycrystalline materials. Powder X-ray diffraction (XRD) analysis shows that all samples are single-phase samples and without any noticeable amount of the secondary phase. X-ray photoelectron spectroscopic (XPS) measurements depict the presence of a mixture of Co3+ and Co4+ valence states in these materials. The Seebeck coefficient (S) of dual-doped materials is significantly enhanced, and electrical resistivities (ρ) and thermal conductivities (κ) are decreased compared to the pristine compound. The maximum thermoelectric power factor (PF = S 2/ρ) and dimensionless figure of merit (zT) obtained for the y = 0.025 sample at 1000 K temperature are ∼3.2 × 10-4 W m-1 K-2 and 0.27, respectively. The zT value for Ca2.95Na0.05Co3.975Mo0.025O9 is about 2.5 times higher than that of the parent Ca3Co4O9 compound. These results demonstrate that dual doping of Na and Mo cations is a promising strategy for improving the high-temperature thermoelectric properties of Ca3Co4O9.

Creation and implementation of the Ottawa Handbook of Emergency Medicine.

Implication Statement Medical students face multiple academic challenges during their transition to clerkship, including the ability to navigate various educational resources and translate acquired knowledge clinically. The Ottawa Handbook of Emergency Medicine (EM) was created by referencing EM textbooks and relevant literature, followed by a local peer-review process. A website metrics assessment was performed to assess student uptake. Implementation of the Ottawa Handbook of EM across Canadian clerkship curriculums is anticipated to bridge the EM knowledge gap for junior learners. Énoncé des implications de la recherche Les étudiants en médecine sont confrontés à de multiples défis académiques au moment de leur transition vers l'externat, notamment à celui de se servir de diverses ressources éducatives et d'appliquer leurs connaissances dans un contexte clinique. Le Guide d'Ottawa de médecine d'urgence (MU) a été élaboré à partir de manuels de MU et de la littérature pertinente, et il a fait l'objet d'un processus local d'examen par les pairs. Une évaluation bibliométrique a été effectuée pour évaluer son utilisation par les étudiants. L'application du Guide d'Ottawa de médecine d'urgence dans le cadre des cursus canadiens d'externat devrait permettre de combler les lacunes qu'auraient les étudiants débutants en matière de médecine d'urgence.

Green Synthesis and Characterization of Copper Nanoparticles Using Fortunella margarita Leaves.

The use of biomaterials in the synthesis of nanoparticles is one of the most up-to-date focuses in modern nanotechnologies and nanosciences. More and more research on green methods of producing metal oxide nanoparticles (NP) is taking place, with the goal to overcome the possible dangers of toxic chemicals for a safe and innocuous environment. In this study, we synthesized copper nanoparticles (CuNPs) using Fortunella margarita leaves' extract, which reflects its novelty in the field of nanosciences. The visual observation of a color change from dark green to bluish green clearly shows the instant and spontaneous formation of CuNPs when the phytochemicals of F. margarita come in contact with Cu+2 ions. The synthesis of CuNPs was carried out at different conditions, including pH, temperature, concentration ratio and time, and were characterized with UV-Vis absorption spectra, scanning electron microscope (SEM) and X-ray diffraction (XRD). The UV-Vis analysis reveals the surface plasmon resonance property (SPR) of CuNPs, showing a characteristic absorption peak at 679 nm, while SEM reveals the spherical but agglomerated shape of CuNPs of the size within the range of 51.26-56.66 nm.

CanadiEM: Accessing a Virtual Community of Practice to Create a Canadian National Medical Education Institution.

BACKGROUND: The rise of free open-access medical education (FOAM) has led to a wide range of online resources in emergency medicine. Canadian physicians have been active contributors to FOAM. OBJECTIVES: We aimed to create a virtual community of practice that would serve as a national platform for collaboration, learning, and knowledge dissemination. METHODS: CanadiEM was formed in 2016 from the merger of two Canadian websites and a podcast. Using a community-of-practice model, we introduced two training programs to support junior community members in becoming core editorial team members and employed asynchronous Web technologies to facilitate collaboration. We also introduced a coached peer review process and formed strategic alliances that aim to ensure a high quality of publication. RESULTS: CanadiEM has become a portal for readers to access a broad range of FOAM content. The website has published 782 articles. Of these, 71 have undergone a coached peer review process. The website has received over 2.5 million page views from 217 countries, and the associated CRACKCast podcast has been downloaded over 750,000 times. CONCLUSIONS: CanadiEM has succeeded in building a national multi-interface dissemination network that fosters collaboration and knowledge sharing in emergency medicine while fostering junior digital scholars. The construction of a community of practice has been facilitated by quality assurance, training programs, and the use of asynchronous Web technologies. Ongoing challenges in sustainability include a volunteer workforce with high turnover.

Exchange-biased hybrid ferromagnetic-multiferroic core-shell nanostructures.

Artificial exchange-biased two-phase core-shell nanostructures consisting of ferromagnetic (Ni) and multiferroic (BiFeO3) materials were manufactured by a two-step method. An exchange bias effect was observed and studied, which indicates that it is possible to fabricate ferromagnetic-multiferroic nanostructures to utilize the combined ferroelectric and antiferromagnetic functionalities of bismuth ferrite.

Computer order entry systems in the emergency department significantly reduce the time to medication delivery for high acuity patients.

BACKGROUND: Computerized physician order entry (CPOE) systems are designed to increase safety and improve quality of care; however, their impact on efficiency in the ED has not yet been validated. This study examined the impact of CPOE on process times for medication delivery, laboratory utilization and diagnostic imaging in the early, late and control phases of a regional ED-CPOE implementation. SETTING: Three tertiary care hospitals serving a population in excess of 1 million inhabitants that initiated the same CPOE system during the same 3-week time window. Patients were stratified into three groupings: Control, Early CPOE and Late CPOE (n = 200 patients per group/hospital site). Eligible patients consisted of a stratified (40% CTAS 2 and 60% CTAS 3) random sample of all patients seen 30 days preceding CPOE implementation (Control), 30 days immediately after CPOE implementation (Early CPOE) and 5-6 months after CPOE implementation (Late CPOE). Primary outcomes were time to (TT) from physician assignment (MD-sign) up to MD-order completion. An ANOVA and t-test were employed for statistical analysis. RESULTS: In comparison with control, TT 1st MD-Ordered Medication decreased in both the Early and Late CPOE groups (102.6 min control, 62.8 Early and 65.7 late, p < 0.001). TT 1st MD-ordered laboratory results increased in both the Early and Late CPOE groups compared to Control (76.4, 85.3 and 73.8 min, respectively, p < 0.001). TT 1st X-Ray also significantly increased in both the Early and Late CPOE groups (80.4, 84.8 min, respectively, compared to 68.1, p < 0.001). Given that CT and ultrasound imaging inherently takes increased time, these imaging studies were not included, and only X-ray was examined. There was no statistical difference found between TT discharge and consult request. CONCLUSIONS: Regional implementation of CPOE afforded important efficiencies in time to medication delivery for high acuity ED patients. Increased times observed for laboratory and radiology results may reflect system issues outside of the emergency department and as a result of potential confounding may not be a reflection of CPOE impact.

Dose and duration of nerve growth factor (NGF) administration determine the extent of behavioral recovery following peripheral nerve injury in the rat.

Nerve growth factor (NGF) has been previously shown to support neuron survival and direct neurite outgrowth in vitro, and to enhance axonal regeneration in vivo. However, a systematic analysis of NGF dose and dose duration on behavioral recovery following peripheral nerve injury in rodents has not been previously investigated. Here, we show that NGF promotes a bell shaped dose-response, with an optimal threshold effect occurring at 800 pg/µl. High dose NGF inhibited regeneration. However, this effect could be reversed through functional blockade of p75 receptors, thus implicating these receptors as mediators of the inhibitory response. Longer term evaluation showed that animals administered NGF at 80 ng/day for 3 weeks had greater sensorimotor recovery compared to all other treatment groups. These animals made significantly fewer errors during skilled locomotion, and displayed both increased vertical and fore-aft ground reaction forces during flat surface locomotion. Furthermore, terminal electrophysiological and myological assessments (EMG, wet gastrocnemius muscle weights) corroborated the behavioral data. Overall, these data support the hypothesis that both appropriate dose and duration of NGF are important determinants of behavioral recovery following nerve injury in the rat.

Collagen nerve conduits promote enhanced axonal regeneration, schwann cell association, and neovascularization compared to silicone conduits.

Peripheral nerve regeneration within guidance conduits involves a critical association between regenerating axons, Schwann cells (SCs), and neovascularization. However, it is currently unknown if there is a greater association between these factors in nonpermeable versus semipermeable nerve guide conduits. We therefore examined this collaboration in both silicone- and collagen-based nerve conduits in both 5- and 10-mm-injury gaps in rat sciatic nerves. Results indicate that collagen conduits promoted enhanced axonal and SC regeneration and association when compared to silicone conduits in the shorter 5-mm-gap model. In addition, collagen tubes displayed enhanced neovascularization over silicone conduits, suggesting that these three factors are intimately related in successful peripheral nerve regeneration. At later time points (1- and 2-month analysis) in a 10-mm-gap model, collagen tubes displayed enhanced axonal regeneration, myelination, and vascularization when compared to silicone-based conduits. Results from these studies suggest that regenerating cables within collagen-based conduits are revascularized earlier and more completely, which in turn enhances peripheral nerve regeneration through these nerve guides as compared to silicone conduits.