747 research outputs found

    Determination of energy-loss factors for slow electrons in hot gases Final report, 28 Apr. 1966 - 15 Aug. 1969

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    Determination of energy loss factors for slow electrons in hot gase

    Leadership and Teamwork in Trauma and Resuscitation.

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    Leadership skills are described by the American College of Surgeons' Advanced Trauma Life Support (ATLS) course as necessary to provide care for patients during resuscitations. However, leadership is a complex concept, and the tools used to assess the quality of leadership are poorly described, inadequately validated, and infrequently used. Despite its importance, dedicated leadership education is rarely part of physician training programs. The goals of this investigation were the following: 1. Describe how leadership and leadership style affect patient care; 2. Describe how effective leadership is measured; and 3. Describe how to train future physician leaders. We searched the PubMed database using the keywords "leadership" and then either "trauma" or "resuscitation" as title search terms, and an expert in emergency medicine and trauma then identified prospective observational and randomized controlled studies measuring leadership and teamwork quality. Study results were categorized as follows: 1) how leadership affects patient care; 2) which tools are available to measure leadership; and 3) methods to train physicians to become better leaders. We included 16 relevant studies in this review. Overall, these studies showed that strong leadership improves processes of care in trauma resuscitation including speed and completion of the primary and secondary surveys. The optimal style and structure of leadership are influenced by patient characteristics and team composition. Directive leadership is most effective when Injury Severity Score (ISS) is high or teams are inexperienced, while empowering leadership is most effective when ISS is low or teams more experienced. Many scales were employed to measure leadership. The Leader Behavior Description Questionnaire (LBDQ) was the only scale used in more than one study. Seven studies described methods for training leaders. Leadership training programs included didactic teaching followed by simulations. Although programs differed in length, intensity, and training level of participants, all programs demonstrated improved team performance. Despite the relative paucity of literature on leadership in resuscitations, this review found leadership improves processes of care in trauma and can be enhanced through dedicated training. Future research is needed to validate leadership assessment scales, develop optimal training mechanisms, and demonstrate leadership's effect on patient-level outcome

    Improved outcomes for hepatic trauma in England and Wales over a decade of trauma and hepatobiliary surgery centralisation

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    Background: Over the last decade trauma services have undergone a reconfiguration in England and Wales. The objective is to describe the epidemiology, management and outcomes for liver trauma over this period and examine factors predicting survival. Methods: Patients sustaining hepatic trauma were identified using the Trauma Audit and Research Network database. Demographics, management and outcomes were assessed between January 2005 and December 2014 and analysed over five, 2-year study periods. Independent predictor variables for the outcome of liver trauma were analysed using multiple logistic regression. Results: 4368 Patients sustained hepatic trauma (with known outcome) between January 2005 and December 2014. Median age was 34 years (interquartile range 23–49). 81% were due to blunt and 19% to penetrating trauma. Road traffic collisions were the main mechanism of injury (58.2%). 241 patients (5.5%) underwent liver-specific surgery. The overall 30-day mortality rate was 16.4%. Improvements were seen in early consultant input, frequency and timing of computed tomography (CT) scanning, use of tranexamic acid and 30-day mortality over the five time periods. Being treated in a unit with an on-site HPB service increased the odds of survival (odds ratio 3.5, 95% confidence intervals 2.7–4.5). Conclusions: Our study has shown that being treated in a unit with an on-site HPB service increased the odds of survival. Further evaluation of the benefits of trauma and HPB surgery centralisation is warranted

    FDCCS16 molecular simulation of the thermophysical properties and phase behaviour of impure CO2 relevant to CCS

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    Impurities from the CCS chain can greatly influence the physical properties of CO2. This has important design, safety and cost implications for the compression, transport and storage of CO2. There is an urgent need to understand and predict the properties of impure CO2 to assist with CCS implementation. However, CCS presents demanding modelling requirements. A suitable model must both accurately and robustly predict CO2 phase behaviour over a wide range of temperature and pressure, and maintain that predictive power for CO2 mixtures with numerous, mutually interacting chemical species. A promising technique to address this task is molecular simulation. It offers a molecular approach, with foundations in firmly established physical principles, along with the potential to predict the wide range of physical properties required for CCS. The quality of predictions from molecular simulation depends on accurate force-fields to de- scribe the interactions between CO2 and other molecules. Unfortunately, there is currently no universally applicable method to obtain force-fields suitable for molecular simulation. In this paper we present two methods of obtaining force-fields: the first being semi-empirical and the second using ab-initio quantum-chemical calculations. In the first approach we optimise the impurity force-field against measurements of the phase and pressure-volume behaviour of CO2 binary mixtures with N2, O2, Ar and H2. A gradient-free optimiser allows us to use the simulation itself as the underlying model. This leads to accurate and robust predictions under conditions relevant to CCS. In the second approach we use quantum-chemical calculations to produce ab-initio evaluations of the interactions between CO2 and relevant impurities, taking N2 as an exemplar. We use a modest number of these calculations to train a machine-learning algorithm, known as a Gaussian process, to describe these data. The resulting model is then able to accurately predict a much broader set of ab-initio force-field calculations at comparatively low numerical cost. Although our method is not yet ready to be implemented in a molecular simulation, we outline the necessary steps here. Such simulations have the potential to deliver first-principles simulation of the thermodynamic properties of impure CO2, without fitting to experimental data

    Three-Port Laparoscopic Cholecystectomy in a Brazilian Amazon Woman with Situs Inversus Totalis: Surgical Approach

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    Situs inversus totalis (SIT) is an uncommon anomaly characterized by transposition of organs to the opposite side of the body in a mirror image of normal. We report on an adult woman, born and resident in Brazilian Amazonia, presenting acute pain located at the left hypochondrium and epigastrium. During clinical and radiological evaluation, the patient was found to have SIT and multiple stones cholelithiasis. Laparoscopic cholecystectomy was safely performed with the three-port technique in a reverse fashion. In conclusion, this case confirms that three-port laparoscopic cholecystectomy is a safe and feasible surgical approach to treat cholelithiasis even in rare and challenging conditions like SIT

    Avoidable mortality from giving tranexamic acid to bleeding trauma patients: an estimation based on WHO mortality data, a systematic literature review and data from the CRASH-2 trial

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    BACKGROUND: The CRASH-2 trial showed that early administration of tranexamic acid (TXA) safely reduces mortality in bleeding in trauma patients. Based on data from the CRASH-2 trial, global mortality data and a systematic literature review, we estimated the number of premature deaths that might be averted every year worldwide through the use of TXA. METHODS: We used CRASH-2 trial data to examine the effect of TXA on death due to bleeding by geographical region. We used WHO mortality data (2008) and data from a systematic review of the literature to estimate the annual number of in-hospital trauma deaths due to bleeding. We then used the relative risk estimates from the CRASH-2 trial to estimate the number of premature deaths that could be averted if all hospitalised bleeding trauma patients received TXA within one hour of injury, and within three hours of injury. Sensitivity analyses were used to explore the effect of uncertainty in the parameter estimates and the assumptions made in the model. RESULTS: There is no evidence that the effect of TXA on death due to bleeding varies by geographical region (heterogeneity p = 0.70). Based on WHO data and our systematic literature review, we estimate that each year worldwide there are approximately 400,000 in-hospital trauma deaths due to bleeding. If patients received TXA within one hour of injury then approximately 128,000 (uncertainty range [UR] ≈ 72,000 to 172,000) deaths might be averted. If patients received TXA within three hours of injury then approximately 112,000 (UR ≈ 68,000 to 148,000) deaths might be averted. Country specific estimates show that the largest numbers of deaths averted would be in India and China. CONCLUSIONS: The use of TXA in the treatment of traumatic bleeding has the potential to prevent many premature deaths every year. A large proportion of the potential health gains are in low and middle income countries
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