bluuebunny/crossref_metadata_2025 huggingface dataset:
Cassava Bagasse as a Substrate to Produce Cyclodextrins
Authors: Pinheiro Keren Hapuque , Watanabe Lycio Shinji , Nixdorf Suzana Lucy , Barão Carlos Eduardo , Pimentel Tatiana Colombo , Matioli Graciette , de Moraes Flavio Faria
Published: May 2018

Cassava bagasse (CB) is an agro‐industry residue usually discarded by starch industries. In this study, CB is used as a substrate to produce cyclodextrins (CDs), due to the high carbohydrate content (62%). The influence of CB concentration (2–4%) and temperature (60–70 °C) on the production of α, β, and γ‐CD was verified by means of the CGTase Toruzyme enzyme. Higher CD production (8.61 mM) is observed for 4% CB at 70 °C. The CB performed similar or better in the CD production and conversion rates when compared to cassava dextrin (CM), the main substrate used for CD production. The addition of 10% ethanol to the reaction medium containing CB doubled the conversion rate to 48.5%. Therefore, CD production with CB can solve the problem of discarding this residue, allowing the production of CDs with lower costs, and can generate additional income for the cassava starch industry.
Structural optimization of jacket supporting structures for offshore wind turbines using colliding bodies optimization algorithm
Authors: Kaveh Ali , Sabeti Sepehr
Published: May 2018

Considering the size and dimension of offshore wind turbine structures, structural optimization of such structures, notwithstanding being outstandingly fruitful, is a tedious task. Nonetheless, in this paper, a metaheuristic algorithm named as colliding bodies optimization is employed when investigating the optimal design of jacket supporting structures for offshore wind turbines. The OC4 reference jacket is considered as the case study, validating the outcomes of this research. To do so, MATLAB is utilized in modeling the structure. The structural optimization is then performed when both ultimate limit state and frequency constraints are being considered. During the optimization process, the weight of the structure is approximately halved, and its first and second frequencies are kept within the considered soft–stiff range (0.21–0.32 Hz).
Damage‐controlled performance‐based design optimization of steel moment frames
Authors: Gholizadeh Saeed , Fattahi Fayegh
Published: May 2018

In the present paper, performance‐based design of steel moment‐resisting frames (SMRFs) is implemented to minimize total cost of the structures. The total cost is summation of the initial construction cost and the seismic damage cost in operational lifetime of the structures subjected to seismic loading. In order to evaluate the seismic damage cost, Park–Ang damage index (DI), as one of the most realistic measures of structural seismic damage, is utilized. To calculate the DI, nonlinear time‐history response of the structure needs to be evaluated during the optimization process. As the computational burden of the process is very high, neural network techniques are utilized to predict the required nonlinear time‐history structural responses. As the design constraints, besides the drift checks at immediate occupancy and collapse prevention performance levels, the global DI is also checked at collapse prevention level to control the amount of seismic damage. In order to achieve the optimization task, a sequential enhanced colliding bodies optimization II is proposed. Numerical studies are conducted to demonstrate the efficiency of the proposed methodology involving 2 illustrative examples of a 6‐story SMRF and a 12‐story SMRF.
Design and implementation of real‐time monitoring and control system supported with IOS/Android application for industrial furnaces
Authors: Yılmaz Cemal , Yılmaz Ercan Nurcan , Işık Mehmet Fatih , Usalan Mehmet Ali Sinan , Sönmez Yusuf , Özdemir Veysel
Published: May 2018

SCADA (supervisory control and data acquisition) systems have been used widely in the manufacturing process in parallel to the rapid advancement of technology in recent years. The quality of products in these systems depends on direct process monitoring and control. Therefore, in this study, a SCADA‐based scale model is developed for real‐time monitoring and control of an industrial furnace by using Android/IOS‐based smartphones. To achieve the desired temperature in the furnace and to keep the energy saving constant, a PLC‐based SCADA system was designed. In the designed system, the furnace temperature is measured continuously by sensors and the furnace voltage is set as analog in order to reach the desired temperature as soon as possible. Different PID parameters are used to achieve this aim. Thus, the product quality is increased and energy efficiency is achieved. © 2018 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
The new middle class in emerging markets: How values and demographics influence discretionary consumption
Authors: Belbağ Aybegüm G. , Üner M. Mithat , Cavusgil Erin , Cavusgil S. Tamer
Published: May 2018

The rise of new middle‐class consumers in rapidly transforming emerging markets has attracted the attention of Western business executives. What they know about this growing segment of customers will determine whether they succeed or fail in these markets. The present study examines the factors that drive the discretionary consumption of this new middle class, including the effects of consumerist values, religious values, occupation, education levels, and ownership of fixed assets. The study draws its insights from data gathered from 391 new middle‐class consumers in Ankara, the second‐largest city in Turkey. The findings provide important implications for businesses, both indigenous and foreign. An overall implication is that managers ought to understand and qualify the new middle class in emerging markets not simply by their access to disposable income but by deeper attitudinal and behavioral characteristics.
Metformin for prevention of hypertensive disorders of pregnancy in women with gestational diabetes or obesity: systematic review and meta‐analysis of randomized trials
Authors: Kalafat E. , Sukur Y. E. , Abdi A. , Thilaganathan B. , Khalil A.
Published: May 2018

Objective

Metformin has been reported to reduce the risk of pre‐eclampsia. It is also known to influence soluble fms‐like tyrosine kinase‐1 level, which correlates significantly with the gestational age at onset and severity of pre‐eclampsia. The main aim of this systematic review and meta‐analysis of randomized trials was to determine whether metformin use is associated with the incidence of hypertensive disorders of pregnancy (HDP).

Methods

MEDLINE (1947 to September 2017), Scopus (1970 to September 2017) and the Cochrane Library (inception to September 2017) were searched for relevant citations in the English language. Only randomized controlled trials on metformin use, reporting the incidence of pre‐eclampsia or pregnancy‐induced hypertension, were included. Studies on populations with a high probability of metformin use prior to randomization (those with type II diabetes or polycystic ovary syndrome) were excluded. Random‐effects models with the Mantel–Haenszel method were used for subgroup analyses. Bayesian random‐effects meta‐regression was used to summarize the evidence.

Results

In total, 3337 citations matched the search criteria. After evaluating 2536 abstracts and performing full‐text review of 52 studies, 15 were included in the review. In women with gestational diabetes, metformin use was associated with a reduced risk of pregnancy‐induced hypertension when compared with insulin (relative risk (RR), 0.56; 95% CI, 0.37–0.85; I2 = 0%; 1260 women) and a non‐significantly reduced risk of pre‐eclampsia (RR, 0.83; 95% CI, 0.60–1.14; I2 = 0%; 1724 women). In obese women, when compared with placebo, metformin use was associated with a non‐significant reduction in risk of pre‐eclampsia (RR, 0.74; 95% CI, 0.09–6.28; I2 = 86%; 840 women). In women with gestational diabetes, metformin use was also associated with a non‐significant reduction in risk of any HDP (RR, 0.71; 95% CI, 0.41–1.25; I2 = 0%; 556 women) when compared with glyburide. When studies were combined using Bayesian random‐effects meta‐regression, with treatment type as a covariate, the posterior probabilities of metformin having a beneficial effect on the prevention of pre‐eclampsia, pregnancy‐induced hypertension and any HDP were 92.7%, 92.8% and 99.2%, respectively, when compared with any other treatment or placebo.

Conclusions

There is a high probability that metformin use is associated with reduced HDP incidence when compared with other treatments or placebo. The small number of studies included in the analysis, the low quality of evidence and the clinical heterogeneity preclude generalization of these results to broader populations. Given the clinical importance of this topic and the magnitude of effect observed in this meta‐analysis, further prospective trials are urgently needed. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.
Patterns of mammal subsistence hunting in eastern Amazon, Brazil
Authors: Pires Mesquita Geison , Domingo Rodríguez‐Teijeiro José , Nascimento Barreto Larissa
Published: May 2018

Hunting affects many threatened mammal species in Brazil. We described subsistence hunting patterns for medium‐ (1.0–14.9 kg) and large‐sized (>15 kg) mammal species by a rural community in the eastern Amazon, Brazil. From April 2012 to November 2013, we observed hunts and conducted semistructured interviews with local hunters. We identified species of game mammals in the region, frequency of capture, capture techniques used for each species, yield of the hunt, and reasons that hunting is practiced in the region. We then performed a correlation analysis and multivariate analysis to determine similarities and differences of mammals hunted in each landscape. We recorded 18 species of harvested animals (n = 132) including common paca (Cuniculus paca), capybara (Hydrochoerus hydrochaeris), southern naked‐tailed armadillo (Cabassous unicinctus), nine‐banded armadillo (Dasypus novemcinctus), and six‐banded armadillo (Euphractus sexcinctus). Endangered species that were hunted included giant armadillo (Priodontes maximus) and white‐lipped peccary (Tayassu pecari). The medium‐sized mammals comprised 75.7% of harvested mammals, whereas 24.2% were large‐sized mammals; however, the latter group represented 55.8% of the mass of harvested meat. Half of all biomass harvested was from rainforests that made up 2.2% of the region. Knowing what, how, why, and where certain species are hunted increases understanding of pressure local communities exert on wild animal populations. As the first study of its kind in the eastern Brazilian Amazon, our study is a basis for further work in relation to effect and sustainability of hunting wildlife, and conservation strategies for medium‐ and long‐term management programs for species conservation at the regional level. © 2018 The Wildlife Society.
Impact of Biliary Drainage on Multidetector‐Row Computed Tomography on R0 Resection of Perihilar Cholangiocarcinoma
Authors: Hosokawa Isamu , Shimizu Hiroaki , Yoshitomi Hideyuki , Furukawa Katsunori , Takayashiki Tsukasa , Miyazaki Masaru , Ohtsuka Masayuki
Published: May 2018

Background

Although multidetector‐row computed tomography (MDCT) before biliary drainage is useful for the assessment of the resectability of perihilar cholangiocarcinoma (PHC), the impact of biliary drainage on MDCT images before surgical resection for PHC has been poorly studied, and its possible consequences for R0 resection of PHC remain unclear. This study was performed to compare the surgical outcomes of patients with PHC who underwent MDCT before versus after biliary drainage.

Methods

All consecutive patients who underwent major hepatectomy extending to segment 1 with extrahepatic bile duct resection for PHC from 2009 to 2016 were retrospectively evaluated. R0 resection was defined as no residual cancer at all surgical margins. Patients with pathological stage IV PHC were excluded.

Results

Of 142 patients who underwent major hepatectomy, 108 were eligible for this study. Of these 108 patients, 64 (59%) and 44 (41%) underwent MDCT before and after biliary drainage, respectively. The total bilirubin concentration at presentation was lower in patients who underwent MDCT before than after biliary drainage (4.1 ± 5.9 vs. 8.0 ± 7.1 mg/ml, respectively; p = 0.002). Although there were no significant differences in the surgical characteristics or pathological stages between the two groups, R0 resection was more frequently achieved in patients who underwent MDCT before than after biliary drainage [46/64 (72%) vs. 22/44 (50%), respectively; p = 0.03]. On multivariate analysis, MDCT before biliary drainage was independently associated with R0 resection of PHC (risk ratio: 2.38, 95% CI 1.05–5.41; p = 0.04).

Conclusions

In selected patients, MDCT should be performed before biliary drainage to achieve R0 resection of PHC.
Construction of an alternative glycerol-utilization pathway for improved β-carotene production in Escherichia coli
Authors: Guo Jin-Ying , Hu Kun-Le , Bi Chang-Hao , Li Qing-Yan , Zhang Xue-Li
Published: May 2018

Glycerol, which is an inevitable by-product of biodiesel production, is an ideal carbon source for the production of carotenoids due to its low price, good availability and chemically reduced status, which results in a low requirement for additional reducing equivalents. In this study, an alternative carbon-utilization pathway was constructed in Escherichia coli to enable more efficient β-carotene production from glycerol. An aldehyde reductase gene (alrd) and an aldehyde dehydrogenase gene (aldH) from Ralstonia eutropha H16 were integrated into the E. coli chromosome to form a novel glycerol-utilization pathway. The β-carotene specific production value was increased by 50% after the introduction of alrd and aldH. It was found that the glycerol kinase gene (garK), alrd and aldH were the bottleneck of the alternative glycerol metabolic pathway, and modulation of garK gene with an mRS library further increased the β-carotene specific production value by 13%. Finally, co-modulation of genes in the introduced aldH–alrd operon led to 86% more of β-carotene specific production value than that of the strain without the alternative glycerol-utilization pathway and the glycerol-utilization rate was also increased. In this work, β-carotene production of E. coli was significantly improved by constructing and optimizing an alternative glycerol-utilization pathway. This strategy can potentially be used to improve the production of other isoprenoids using glycerol as a cheap and abundant substrate, and therefore has industrial relevance.
On the Influence of Nb/Ti Ratio on Environmentally-Assisted Crack Growth in High-Strength Nickel-Based Superalloys
Authors: Németh A. A. N. , Crudden D. J. , Collins D. M. , Kuksenko V. , Liebscher C. H. , Armstrong D. E. J. , Wilkinson A. J. , Reed R. C.
Published: May 2018

The effect of Nb/Ti ratio on environmentally-assisted crack growth of three prototype Ni-based superalloys is studied. For these alloys, the yield strength is unaltered with increasing Nb/Ti ratio due to an increase in grain size. This situation has allowed the rationalization of the factors influencing damage tolerance at 700 °C. Primary intergranular cracks have been investigated using energy-dispersive X-ray spectroscopy in a scanning transmission electron microscope and the analysis of electron back-scatter diffraction patterns. Any possible detrimental effect of Nb on the observed crack tip damage due to Nb-rich oxide formation is not observed. Instead, evidence is presented to indicate that the tertiary γ′-precipitates are dissolving ahead of the crack consistent with the formation of oxides such as alumina and rutile. Our results have implications for alloy design efforts; at any given strength level, both more and less damage-tolerant variants of these alloys can be designed.
Deformation-Induced Microstructural Banding in TRIP Steels
Authors: Celotto S. , Ghadbeigi H. , Pinna C. , Shollock B. A. , Efthymiadis P.
Published: May 2018

Microstructure inhomogeneities can strongly influence the mechanical properties of advanced high-strength steels in a detrimental manner. This study of a transformation-induced plasticity (TRIP) steel investigates the effect of pre-existing contiguous grain boundary networks (CGBNs) of hard second-phases and shows how these develop into bands during tensile testing using in situ observations in conjunction with digital image correlation (DIC). The bands form by the lateral contraction of the soft ferrite matrix, which rotates and displaces the CGBNs of second-phases and the individual features within them to become aligned with the loading direction. The more extensive pre-existing CGBNs that were before the deformation already aligned with the loading direction are the most critical microstructural feature for damage initiation and propagation. They induce micro-void formation between the hard second-phases along them, which coalesce and develop into long macroscopic fissures. The hard phases, retained austenite and martensite, were not differentiated as it was found that the individual phases do not play a role in the formation of these bands. It is suggested that minimizing the presence of CGBNs of hard second-phases in the initial microstructure will increase the formability.
New perspectives in fire management in South American savannas: The importance of intercultural governance
Authors: Mistry Jayalaxshmi , Schmidt Isabel Belloni , Eloy Ludivine , Bilbao Bibiana
Published: May 2018

Wildfires continue to cause damage to property, livelihoods and environments around the world. Acknowledging that dealing with wildfires has to go beyond fire-fighting, governments in countries with fire-prone ecosystems have begun to recognize the multiple perspectives of landscape burning and the need to engage with local communities and their practices. In this perspective, we outline the experiences of Brazil and Venezuela, two countries where fire management has been highly contested, but where there have been recent advances in fire management approaches. Success of these new initiatives have been measured by the reduction in wildfire extent through prescribed burning, and the opening of a dialogue on fire management between government agencies and local communities. Yet, it is clear that further developments in community participation need to take place in order to avoid the appropriation of local knowledge systems by institutions, and to better reflect more equitable fire governance.
Reassessing the Effect of Colour on Attitude and Behavioural Intentions in Promotional Activities: The Moderating Role of Mood and Involvement
Authors: Rizomyliotis Ioannis , Konstantoulaki Kleopatra , Kostopoulos Ioannis
Published: May 2018

The present research examines the effect of background colour on attitude and behavioural intentions in various promotional activities taking into consideration the moderating role of mood and involvement. Three experiments reflecting different promotional activities (window display, consumer trade show, guerrilla marketing) were conducted for this purpose. Overall, findings indicate that cool background colours, in contrast to warm colours, induce more positive attitudes and behavioural intentions mainly in positive mood, and low involvement conditions. Implications are also discussed.
Effect of prenatal stress on ɑ5 GABAA receptor subunit gene expression in hippocampus and pilocarpine induced seizure in rats
Authors: Nejatbakhsh Mehrdad , Saboory Ehsan , Bagheri Morteza
Published: May 2018

The GABAergic synapses go through structural and functional maturation during early brain development. Maternal stress alters GABAergic synapses in developing brain, which are associated with the pathophysiology of neuropsychiatric disorders in adults. The present study aimed to investigate the effect of prenatal restraint stress (PS) on pilocarpine‐induced seizure and ɑ5 subunit of γ‐amino butyric acid type A (GABAA) receptor expression in hippocampus. Pregnant Wistar rats were subjected to PS at gestational days 15–17 and the pups were examined for susceptibility to seizure and ɑ5 subunit of GABAA receptor expression in hippocampus at postnatal days 14 and 21 (P14 and PND 21). Quantitative real‐time PCR was used for evaluating the gene expression in the pups. Pilocarpine was injected intraperitoneally into the pups and seizure behaviors were recorded. The results showed that ɑ5 subunit mRNA expression significantly increased in hippocampus at both the P14 and P21 in the stressed rats. However, ɑ5 subunit level was greater at the P21 than at the P14 in both the groups. Latency of first tonic‐clonic seizure significantly decreased in the PS group compared to the control pups. Number and duration of tonic–clonic seizures increased in the PS rats compared to the controls. PS led to an increase in total score of seizure at the P14 and P21. It can be concluded that PS increases the seizure susceptibility and GABAA receptor ɑ5 subunit gene expression in offspring; it is likely that the mechanism of increased seizure susceptibility by PS, at least in part, can increase the GABAA receptor ɑ5 subunit gene expression in hippocampus.
COMPOUND POISSON CLAIMS RESERVING MODELS: EXTENSIONS AND INFERENCE
Authors: Meng Shengwang , Gao Guangyuan
Published: May 2018

We consider compound Poisson claims reserving models applied to the paid claims and to the number of payments run-off triangles. We extend the standard Poisson-gamma assumption to account for over-dispersion in the payment counts and to account for various mean and variance structures in the individual payments. Two generalized linear models are applied consecutively to predict the unpaid claims. A bootstrap is used to estimate the mean squared error of prediction and to simulate the predictive distribution of the unpaid claims. We show that the extended compound Poisson models make reasonable predictions of the unpaid claims.
LO39: Stress inoculation training: a critical review for emergency medicine
Authors: McParland A. , Hicks C.
Published: May 2018

Introduction: In high stakes, performance-oriented professions, the ability to execute in stressful situations is both a prerequisite and an intense focus of training. Stress Inoculation Training (SIT) is a three-step cognitive-behavioural intervention aimed at reducing stress that may play a role in helping EM teams prepare for high acuity events. We conducted a systematic review of literature in medicine and performance-oriented professions to inform the development of an EM-focused SIT curriculum. Methods: An electronic search of Ovid MEDLINE, Web of Science Core Collection, PsychINFO, ProQuest and Scopus was conducted. Inclusion criteria were studies investigating the impact of stress inoculation training on performance and anxiety reduction. Data extraction included recording of performance and anxiety domains measured in each study and the details of how the stress inoculation training was delivered. Screening of articles, data extraction, and summarization were conducted by two independent reviewers using a standardized data extraction tool. Results: Our search yielded 431 studies; 40 were screened for full-text review and 10 met inclusion criteria. A total of 930 trainees throughout the 10 studies were enrolled. Four studies consisted of students in varying disciplines, including law, technology, education, and general undergraduate students, and 4 studies were composed of military personnel. No papers directly examined the effect of stress inoculation training on performance in healthcare. A change in performance and a reduction in anxiety and/or stress was noted in 90% of studies. Training length, experience of trainer, or group size did not appear to impact outcomes. Notably, heart rate variability (HRV) did not appear to be affected throughout the studies included, while cortisol and subjective stress were consistently reduced. Conclusion: SIT is an effective tool for enhancing performance and reducing stress and anxiety in high intensity environments. Studies examining the effect of EM-focused SIT on individual, team and patient-orient outcomes are needed.
LO40: Describing CCFP(EM) programs in Canada: a national survey of program directors
Authors: Nath A. , Yadav K. , Perry J. J.
Published: May 2018

Introduction: Enhanced skills training in emergency medicine (EM) for family physicians (CCFP(EM)) has existed since the 1970s. Accreditation standards define what every program must and should have, yet little is known on what is currently done across Canada. Our objectives were to: 1) describe major components of CCFP(EM) programs; and 2) determine how programs incorporate these components into their curriculum. Methods: A rigorous development process included expert content development and in-person pilot testing using Royal College Emergency Medicine Program Directors. An electronic survey questionnaire comprised of 63 questions was administered to all 17 CCFP(EM) program directors using a modified Dillman technique. Non-responders were sent a reminder email every 2 weeks over a 6-week period and an in-person reminder was given to non-responders at a face to face meeting 4 weeks after the initial survey was sent in June 2016. Results: All 17/17 (100%) program directors responded. There was considerable variation in administrative structure and financial support for each program. All programs provided ultrasound courses for basic skills (trauma, abdominal aortic aneurysm, intrauterine pregnancy). Variation exists for offering independent ultrasound certification (77%), advanced scanning (18%) and protected academic time for scanning (53%). All programs utilize high fidelity simulation. Some programs use in situ simulation (18%) and hold a simulation boot camp (41%). Most centres required an academic project, most commonly a quality assurance project (53%) and/or a critical appraisal of the literature (59%). Publication or national conference presentations were required by 12% of programs. Competency based assessments use simulation (88%) and direct observations (53%). Only 24% of programs have a transition to practice curriculum. All programs maintain strong connections to family medicine. Conclusion: This study demonstrates diverse structures of CCFP(EM) programs across Canada. Programs are similar regarding the provision of ultrasound, simulation and protected teaching time. Variation exists in administrative structure and financial resources of each program, academic project requirements, and how programs perform competency based assessments.
LO48: Does FAST change management of blunt trauma patients?
Authors: Thavanathan R. , Stiell I. G. , Levac-Martinho O. , Worrall J. , Ritcey B. W.
Published: May 2018

Introduction: Despite widespread use of FAST in trauma, there is a lack of data supporting its usefulness. We sought to identify the impact of FAST on clinical management of blunt trauma patients. Methods: This health records review was conducted at a single large academic Level 1 trauma center emergency department. Patients with a suspicion of acute blunt traumatic abdominal injury were identified from our health records database. Data were collected regarding FAST utilization, CT scan utilization and timing, need for definitive management, disposition, and length of stay (LOS). Results: 285 patients were included, 152 (53.3%) received a FAST examination, with 33 (22%) having a direct impact on clinical management. CT was performed in 112 (73.6%) of the FAST group, with mean time to imaging of 147.4 minutes, time to trauma team assessment of 21.5 minutes, and ED-LOS of 8.6 hours. In the non-FAST group, 33 (24.8%) received a CT, with time to imaging of 133 minutes, time to trauma team assessment of 133 minutes, and ED-LOS of 13.8 hours. 75.6% of the FAST group required admission and 9.2% required definitive management; admission was needed for 38.3% of the non-FAST group and 2.2% required definitive management. Conclusion: This is the first study to assess patient outcomes with respect to FAST in the era of early whole body CT in trauma. Although FAST does not directly impact care for the majority of blunt trauma patients, it demonstrates usefulness in some patients by directing CT utilization and expediting disposition from the ED.
LO51: Increased mortality and costs in emergency department sepsis patients with delayed intensive care unit admission
Authors: Fernando S. M. , Rochwerg B. , Reardon P. M. , Thavorn K. , Shapiro N. I. , Seely A. J.E. , Perry J. J. , Barnaby D. P. , Tanuseputro P. , Kyeremanteng K.
Published: May 2018

Introduction: Sepsis remains a major cause of mortality. In the Emergency Department (ED), rapid identification and management of sepsis have been associated with improved outcomes. Following ED assessment, patients with infection may be directly admitted to the Intensive Care Unit (ICU), or alternatively admitted to hospital wards or sent home, with risk of future deterioration necessitating ICU admission. Little is known regarding outcomes and costs of ICU sepsis patients who are initially admitted to a ward or discharged home (delayed ICU admission), as compared to those with direct ICU admission from the ED. Methods: We analyzed a prospectively collected registry (2011-2014) of patients admitted to the ICU with a diagnosis of sepsis at two academic hospitals. We included all adult patients with an index ED visit within 72 hours of ICU admission. Patients were categorized into 3 groups: 1) Admitted directly to ICU; 2) Admitted to wards, with ICU admission within 72 hours; and 3) Sent home, with ICU admission within 72 hours. ICU length of stay (LOS) and total costs (both direct and indirect) were recorded. The primary outcome, in-hospital mortality, was analyzed using a multivariable logistic regression model, controlling for confounding variables (including patient sex, comorbidities, and illness severity). Results: 657 ICU patients were included. Of these, 338 (51.4%) were admitted directly from ED to ICU, 246 (37.4%) were initially admitted to the wards, and 73 (11.1%) were initially sent home. In-hospital mortality was lowest amongst patients admitted directly to the ICU (29.5%), as compared to patients admitted to ICU from wards (42.7%), or home (61.6%). Delayed ICU admission was associated with increased odds of mortality (adjusted odds ratio 1.85 [1.24-2.76], P<0.01) and increased median ICU LOS (11 days vs. 4 days, P<0.001). Median total costs were lowest among patients directly admitted to the ICU ($19,924, [Interquartile range [IQR], 10,333-32,387]), as compared to those admitted from wards ($72,155 [IQR, $42,771-122,749]) and those initially sent home ($45,121 [IQR, $19,930-86,843]). Conclusion: Only half of ED sepsis patients ultimately requiring ICU admission within 72 hours of ED arrival are directly admitted to the ICU. Delayed ICU admission is associated with higher mortality, LOS, and costs.
LO54: Prospective mulitcenter validation of the Canadian syncope risk score
Authors: Thiruganasambandamoorthy V. , Mukarram M. , Sivilotti M. L.A. , Yan J. , Sage N. Le , Huang P. , Stiell I. G. , Nemnom M. , Wells G. A. , Taljaard M.
Published: May 2018

Introduction: The Canadian Syncope Risk Score (CSRS) was developed to identify patients at risk for serious adverse events (SAE) within 30 days of an Emergency Department (ED) visit for syncope. We sought to validate the score in a new cohort of ED patients. Methods: We conducted a multicenter prospective cohort study at 8 large academic tertiary-care EDs across Canada from March 2014 to Dec 2016. We enrolled adults (age 16 years) who presented within 24 hours of syncope, after excluding those with persistent altered mentation, witnessed seizure, intoxication, and major trauma requiring hospitalization. Treating ED physicians collected the nine CSRS predictors at the index visit. Adjudicated SAE included death, arrhythmias and non-arrhythmic SAE (myocardial infarction, serious structural heart disease, pulmonary embolism, severe hemorrhage and procedural interventions within 30-days). We assessed area under the Receiver Operating Characteristic (ROC) curve, score calibration, and the classification performance for the various risk categories. Results: Of the 2547 patients enrolled, 146 (5.7%) were lost to follow-up and 111 (4.3%) had serious condition during the index ED visit and were excluded. Among the 2290 analyzed, 79 patients (3.4%; 0.4% death, 1.4% arrhythmia) suffered 30-day serious outcomes after ED disposition. The accuracy of the CSRS remained high with area under the ROC curve at 0.87 (95%CI 0.82-0.92), similar to the derivation phase (0.87; 95%CI 0.84-0.89). The score showed excellent calibration at the prespecified risk strata. For the very-low risk category (0.3% SAE of which 0.2% were arrhythmia and no deaths) the sensitivity was 97.5% and negative predictive value was 99.7% (95%CI 98.7-99.9). For the very high-risk category (61.5% SAE of which 26.9% were arrhythmia and 11.5% death) the specificity was 99.4% and positive predictive value was 61.5% (95% CI 43.0-77.2). Conclusion: In this multicenter validation study, the CSRS accurately risk stratified ED patients with syncope for short-term serious outcomes after ED disposition. The score should aid in minimizing investigation and observation of very-low risk patients, and prioritization of inpatient vs outpatient investigations or following of the rest. The CSRS is ready for implementation studies examining ED management decisions, patient safety and health care resource utilization.
LO55: Role of n-terminal pro brain natriuretic peptide (NT Pro-BNP) in emergency department syncope risk stratification: a multicenter study
Authors: Thiruganasambandamoorthy V. , Sivilotti M. L.A. , McRae A. D. , Stiell I. G. , Mukarram M. , Huang L. , Arcot K. , Wells G. A. , Rowe B. H.
Published: May 2018

Introduction: Two published studies reported natriuretic peptides can aid in risk-stratification of Emergency Department (ED) syncope. We sought to assess the role of N-Terminal pro Brain Natriuretic Peptide (NT pro-BNP) to identify syncope patients at risk for serious adverse events (SAE) within 30 days of the ED visit, and its value above that of the Canadian Syncope Risk Score (CSRS). Methods: We conducted a multicenter prospective cohort study at 6 large Canadian EDs from Nov 2011 to Feb 2015. We enrolled adults who presented within 24-hours of syncope and excluded those with persistent altered mentation, obvious seizure, and intoxication. We collected patient characteristics, nine CSRS predictors (includes troponin), ED management and NT pro-BNP levels. Adjudicated serious adverse events (SAE) included death, cardiac SAE (arrhythmias, myocardial infarction, serious structural heart disease) and non-cardiac SAE (pulmonary embolism, severe hemorrhage and procedural interventions within 30-days). We used two tailed t-test and logistic regression analysis. Results: Of the 1359 patients (mean age 57.2 years, 54.7% females, 13.3% hospitalized) enrolled, 148 patients (10.9%; 0.7% deaths, 7.9% cardiac SAE including 6.1% arrhythmia) suffered SAE within 30-days. The mean NT pro-BNP values, when compared to the patients with no SAE (499.8ng/L) was significantly higher among the 56 patients who suffered SAE after ED disposition (3147ng/L, p=0.001), and among the 35 patients with cardiac SAE after ED disposition (2016.2ng/L, p=0.02). While there was a trend to higher levels among patients who suffered arrhythmia after the ED visit, it was not statistically significant (1776.4ng/L, p=0.07). In a model with CSRS predictors, the adjusted odds ratio for NT pro-BNP was 8.0 (95%CI 1.8, 35.9) and troponin was 3.8 (95%CI 1.7, 8.8). The addition of NT pro-BNP did not significantly improve the classification performance (p=0.76) with areas under the curves for CSRS was 0.91 (95%CI 0.88, 0.95) and CSRS with NT pro-BNP was 0.92 (95%CI 0.88, 0.95). Conclusion: In this multicenter study, mean NT pro-BNP levels were significantly higher among ED syncope patients who suffered SAE including cardiac SAE after ED disposition. Though NT pro-BNP was a significant independent predictor of SAE after ED disposition, it did not improve accuracy in ED syncope risk-stratification when compared to CSRS. Hence, we do not recommend NT pro-BNP measurement for ED syncope management.
LO57: Very low concentrations of high-sensitivity troponin T at presentation can rapidly exclude acute myocardial infarction in a significant proportion of ED chest pain patients
Authors: Andruchow J. E. , Boyne T. S. , Vatanpour S. , Wang D. , McRae A. D.
Published: May 2018

Introduction: Chest pain is one of the most common presenting complaints to emergency departments (EDs) across the world, and the exclusion of acute myocardial infarction (AMI) using troponin testing is central to the care of many of these patients. While testing strategies using conventional troponin assays require repeat testing over many hours to avoid missed diagnoses, high-sensitivity troponin (hs-cTn) assays may be able to exclude AMI in a large proportion of patients with a single result at presentation. This objective of this study is to validate the ability of very low concentrations of hs-cTn at presentation to exclude AMI in ED chest pain patients. Methods: This prospective cohort study was conducted at a single urban tertiary center and regional percutaneous coronary intervention site in Calgary, Alberta. Patients were eligible for enrolment if they presented to the ED with chest pain, were 25-years or older and required biomarker testing to rule out AMI at the discretion of the attending emergency physician. Patients were excluded if they had clear acute ischemic ECG changes, new arrhythmia or renal failure requiring hemodialysis. A high-sensitivity troponin result (Roche Elecsys hs-cTnT) was obtained in all patients at presentation. The primary outcome was AMI on the index visit. Secondary outcomes included 30-day AMI and major adverse cardiac events (MACE - including AMI, revascularization or cardiac death). Electronic medical records were reviewed and telephone follow-up was obtained for all patients at 30-days to ensure relevant events were captured. Two physician adjudication (board-certified emergency physician and cardiologist) was obtained for all outcomes. This study was REB approved. Results: A total of 1,167 patients were enrolled from August 2014 September 2016, of which 191 (16.3%) patients had an initial troponin below the limit of blank (LoB, <3 ng/L) and 416 (32.8%) were below the limit of detection (LoD, <5 ng/L). The sensitivity of a single troponin below the LoB (<3 ng/L) for index AMI was 100% (95% CI 96.2%-100%) and for 30-day AMI was 100% (95% CI 96.4-100%). The sensitivity of a troponin below the LoD (<5 ng/L) for index AMI was 97.9% (95% CI 92.7%-99.8%) and for 30-day AMI was 98.0% (95% CI 93.0-99.8%). Sensitivity for 30-day MACE at both cutoffs was lower: 98.4% (95% CI 94.3-99.8%) for <3 ng/L, and 94.4% (95% CI 88.8-97.7%) for <5 ng/L, respectively; however, negative predictive values remained high at both cutoffs: <3 ng/L, 99.0% (95% CI 96.3-99.9%) and <5 ng/L, 98.3% (95% CI 96.6-99.3%). Conclusion: A high sensitivity troponin T result below the LoB (<3 ng/L) is highly sensitive for excluding AMI and identifies patients at low risk of 30-day MACE. A result below the LoB (<5 ng/L) will identify a larger population of patients as low risk but has a greater risk of missed AMI and MACE.
LO58: Long-term outcomes among emergency department syncope patients: a systematic review
Authors: Leafloor C. , Hong P. Jiho , Sikora L. , Elliot J. , Mukarram M. , Thiruganasambandamoorthy V.
Published: May 2018

Introduction: Approximately 50% of patients discharged from the Emergency Department (ED) after syncope have no cause found. Long-term outcomes among syncope patients are not well studied, to guide physicians regarding outpatient testing and follow-up. The objective of this study was to conduct a systematic review for long-term (one year) outcomes among ED patients with syncope. We aim to use the results of this review to guide us in prospective analysis of one year outcomes with our large database of syncope patients. Methods: We searched Cochrane Central Register of Controlled Trials, Medline and Medline in Process, PubMed, Embase, and the Cumulative Index to Nursing and Allied Health Literature (CINAHL) from the inception to June, 2017. We included studies that reported long-term outcomes among adult ED patients (16 years or older) with syncope. We excluded studies on pediatric patients, and studies that included syncope mimickers: pre-syncope, seizure, intoxication, loss of consciousness after head trauma. We also excluded case reports, letters to the editor and review articles. Outcomes included death, syncope recurrence requiring hospitalization, arrhythmias and procedural interventions for arrhythmias. We selected articles based on title and abstract review during phase-1 and conducted full article review during phase-2. Meta-analysis was performed by pooling the outcomes using random effects model (RevMan v.5.3; Cochrane Collaboration). Results: Initial literature search generated 2094 articles after duplicate removal. 50 articles remained after phase-1 (=0.85) and 16 articles were included in the systematic review after phase-2 (=0.86). The 16 included studies enrolled a total of 44,755 patients. Pooled analysis at 1-year follow-up showed the following outcomes: 7% mortality; 14% recurrence of syncope requiring hospitalization; one study reported that 0.6% of patients had a pacemaker inserted; and two studies reported 0.8 11.5% of patients suffered new arrhythmias. Conclusion: An important proportion of ED patients with syncope suffer outcomes at 1-year. Appropriate follow-up is needed to prevent long-term adverse outcomes. Further prospective research to identify patients at risk for long-term important cardiac outcomes and death is needed.
LO59: External validation of a 2-hour rapid diagnostic algorithm for ruling out acute myocardial infarction in emergency department patients with chest pain using a high-sensitivity troponin-T assay
Authors: Andruchow J. E. , Boyne T. S. , Vatanpour S. , Wang D. , McRae A. D.
Published: May 2018

Introduction: Ruling out acute myocardial infarction (AMI) using serial troponin testing is central to the care of many emergency department (ED) patients with chest pain. While diagnostic strategies using conventional troponin assays require repeat sampling over many hours to avoid missed diagnoses, serial high-sensitivity troponin (hs-cTn) assays may be able to exclude AMI in most patients within 1 or 2 hours. However, many of the initial studies deriving and validating these rapid diagnostic algorithms had all hs-cTn samples analyzed in a central core lab likely representing optimal assay performance. This objective of this study is to validate a 2-hour rapid diagnostic algorithm to exclude AMI in ED chest pain patients using an hs-cTn assay in real world practice. Methods: This prospective cohort study was conducted at a single urban tertiary center and regional percutaneous coronary intervention site in Calgary, Alberta. Patients were eligible for enrolment if they presented to the ED with chest pain, were 25-years or older and required biomarker testing to rule out AMI at the discretion of the attending emergency physician. Patients were excluded if they had clear acute ischemic ECG changes, new arrhythmia or renal failure requiring hemodialysis. A high-sensitivity troponin result (Roche Elecsys hs-cTnT) was obtained in all patients at ED presentation and 2-hours later. The primary outcome was AMI on the index visit. Secondary outcomes included 30-day AMI and 30-day major adverse cardiac events (MACE - including AMI, revascularization or cardiac death). Electronic medical records were reviewed and telephone follow-up was obtained for all patients at 30-days to ensure relevant events were captured. Two physician adjudication (board-certified emergency physician and cardiologist) was obtained for all outcomes. This study was REB approved. Results: A total of 549 patients were enrolled from August 2014 September 2016 with 2-hour serial hs-cTnT results, of which 349 (63.6%) met the 2-hour rapid diagnostic algorithm low risk criteria (time 0 h/2 h hs-cTnT <14 ng/L and delta 2 h <4 ng/L). The sensitivity of the 2-hour low risk criteria for index AMI was 98.4% (95% CI 91.3%-100%) and for 30-day AMI was 98.4% (95% CI 91.6-100%). The sensitivity for 30day MACE was lower 84.4% (95% CI 74.4-91.7%) but maintained a high negative predictive value, 96.6% (95% CI 94.1-98.2%). Conclusion: A 2-hour rapid diagnostic algorithm using an hs-cTnT assay was highly sensitive for AMI on the index visit and successfully identified patients at low risk of 30-day AMI. Sensitivity for MACE was lower, reminding us that while biomarker-only rapid diagnostic algorithms excel at ruling out AMI, careful clinical risk stratification is needed to avoid missed MACE events.
LO60: Diagnostic utility of creatine kinase in the diagnosis and management of non-ST elevation myocardial infarction
Authors: Lam B. , Chaudry H. , Kim S. , Nemnom M. , Stiell I. G. , Hebert G. , Taljaard M. , Beanlands R. , Wells G. A. , Booth R. , Mukarram M. , Thiruganasambandamoorthy V.
Published: May 2018

Introduction: Creatine kinase (CK) measurement, despite not being recommended for the diagnosis of a Non-ST Elevation Myocardial Infarction (NSTEMI) is still routinely performed in the emergency department (ED) for the workup of NSTEMI. The diagnostic utility of CK among ED patients with suspected NSTEMI is still not well understood. The objectives of this study were to assess: the additional value of CK in NSTEMI diagnosis and the correlation between the highest CK/TNI values and ejection fraction (EF) on follow-up echocardiography among patients with suspected NSTEMI. Methods: This was a prospective cohort study conducted at the Civic and General Campuses of The Ottawa Hospital from March 2014 to March 2016. We enrolled adults (18 years) for whom troponin (TNI) and CK were ordered for chest pain or non-chest pain symptoms within the past 24 hours concerning for NSTEMI and excluded those with suspected ST-Elevation Myocardial Infarction (STEMI). Primary outcome was a 30-day NSTEMI adjudicated by two blinded physicians. Demographics, medical history, and ED CK/TNI values were collected. We used descriptive statistics and report test diagnostic characteristics. Results: Of the 1,663 patients enrolled, 84 patients (5.1%) suffered NSTEMI. The sensitivity and specificity of CK was 30.9% (95%CI 21.1, 40.8) and 91.4% (95%CI 90.0, 92.8) respectively. The sensitivity and specificity of troponin was 96.4% (95%CI 92.4, 100) and 88.1% (95%CI 86.5, 89.7) respectively. Among 3 (0.2%) patients with missed NSTEMI diagnosis with TNI, CK measurements did not add value. The mean CK values were not significantly different between those with normal and abnormal EF on follow-up (132.4 U/L and 146.3 U/L respectively; p=0.44), whereas the mean TNI values were significantly different (0.5 µg/L and 1.3 µg/L respectively; p=0.046). Conclusion: CK measurements neither provide any additional value in the work-up of NSTEMI in the ED nor correlate with EF on follow-up. Discontinuing routine CK measurements would reduce overall costs and improve resource utilization in the ED, and streamline the management of patients in the ED with chest pain.