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Critical Situations (critical + situation)
Selected AbstractsTraining scenario prototyping for VR-based simulation of neonatal decision-makingCOMPUTER APPLICATIONS IN ENGINEERING EDUCATION, Issue 4 2007A. Holobar Abstract This paper presents the design and implementation of a real-time system for virtual reality (VR)-based training in neonatal medicine, with main emphasis on simple creation of various training scenarios. This system combines an articulated 3D model of a virtual newborn with text-based descriptions of its physiological and behavioral responses, enabling medical experts to easily construct, simulate and revise an arbitrary postnatal critical situation. Afterwards, the resulting descriptions of newborn's behavior can be used for technical specifications (and even for automatic generation) of more complex behavioral models, such as finite-state automata. © 2007 wiley Periodicals, Inc. Comput Appl Eng Educ 15: 317,328, 2007; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20121 [source] Intraductal chilled saline perfusion to prevent bile duct injury during percutaneous radiofrequency ablation for hepatocellular carcinomaJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 8pt2 2008Takaya Ohnishi Abstract Background and Aim:, Radiofrequency ablation (RFA) is a promising, minimally invasive treatment for hepatocellular carcinoma (HCC). However, thermal injury sometimes occurs in the bile duct, potentially leading to a critical situation. The aim of the present study was to investigate whether bile duct injury is reduced by an intraductal chilled saline perfusion (ICSP) through a nasobiliary tube during RFA for HCC. Patients and Methods:, The baseline incidence of bile duct injury at Gifu Municipal Hospital was 3.1% (13 patients) in 424 patients with HCC treated by percutaneous RFA. In all patients, the tumor was within 5 mm of the central bile duct on CT images. The incidence of bile duct injury was 46% among the 28 selected patients whose tumor was close to the central bile duct. To prevent complications in such high-risk patients, we placed a nasobiliary tube endoscopically before RFA, and performed ICSP during RFA. Forty consecutive patients with tumors close to the central bile duct were enrolled in this study. Results:, Of the 40 enrolled patients, only one had biliary injury, whereas the remaining 39 patients were able to avoid it. The incidence of biliary injury was significantly reduced in the ICSP group (1/40, 2.5%) compared to that in the control group (13/28, 46%) (P < 0.0001). Moreover, the liver function 6 months after RFA was also better preserved in the ICSP group according to Child,Pugh grading, thus resulting in a better clinical outcome. Conclusions:, ICSP through a nasobiliary tube is a potential intervention method to prevent biliary injury by percutaneous RFA. [source] Snap: A time critical decision-making framework for MOUT simulationsCOMPUTER ANIMATION AND VIRTUAL WORLDS (PREV: JNL OF VISUALISATION & COMPUTER ANIMATION), Issue 3-4 2008Shang-Ping Ting Abstract Deliberative reasoning based on the rational analysis of various alternatives often requires too much information and may be too slow in time critical situations. In these situations, humans rely mainly on their intuitions rather than some structured decision-making processes. An important and challenging problem in Military Operations on Urban Terrain (MOUT) simulations is how to generate realistic tactical behaviors for the non-player characters (also known as bots), as these bots often need to make quick decisions in time-critical and uncertain situations. In this paper, we describe our work on Snap, a time critical decision-making framework for the bots in MOUT simulations. The novel features of Snap include case-based reasoning (CBR) and thin slicing. CBR is used to make quick decisions by comparing the current situation with past experience cases. Thin slicing is used to model human's ability to quickly form up situation awareness under uncertain and complex situations using key cues from partial information. To assess the effectiveness of Snap, we have integrated it into Twilight City, a virtual environment for MOUT simulations. Experimental results show that Snap is very effective in generating quick decisions during time critical situations for MOUT simulations. Copyright © 2008 John Wiley & Sons, Ltd. [source] Ethics Seminars: Withdrawal of Treatment in the Emergency Department,When and How?ACADEMIC EMERGENCY MEDICINE, Issue 12 2006Kelly Bookman MD Abstract Although increasing discussion has occurred within emergency medicine about indications for withholding cardiac life support and other resuscitative interventions, emergency physicians (EPs) may be less familiar with the ethical, legal, and practical issues surrounding withdrawal of life support that has already been initiated. Both physicians and out-of-hospital personnel must act rapidly in critical situations and must assume that the patient has the desire to be resuscitated, unless clear evidence exists to the contrary. Often, only after initial life-saving actions have stabilized the patient is there time to reflect and determine a patient's desires regarding such interventions. When the EP can clearly discern a patient's previously stated wishes during the emergency department (ED) stay, these wishes should be honored in the ED. Respecting a patient's request to avoid unwanted, invasive treatments near death may involve withdrawing interventions that could not be withheld during the first few minutes of care. In this article, the authors use a case of out-of-hospital stabilization of a patient as a springboard to review the ethical and legal framework for withdrawal of life-sustaining care, as well as the practical issues involved with withdrawal of such care in the ED. [source] Review of mannequin-based high-fidelity simulation in emergency medicineEMERGENCY MEDICINE AUSTRALASIA, Issue 1 2008Peter Z Fritz Abstract The spectrum of uses of high-fidelity simulation in emergency medicine has increased in the past 10 years and ranges from teaching isolated skills to improving complex team behaviours in critical situations. This review will describe these published uses and explore the evidence supporting the use of high-fidelity simulation, as well as the future directions and difficulties of using this technology in our specialty. [source] Putting value of information theory into practice: a methodology for building sequential decision support systemsEXPERT SYSTEMS, Issue 2 2004Silvano MussiArticle first published online: 7 MAY 200 Abstract: The paper presents a methodology for building sequential decision support systems based on decision theory using value of information (for short, DT-VOI based SDSSs). DT-VOI based SDSSs support decision-makers in difficult problems of sequential decision-making. In particular we consider the problem of building DT-VOI based SDSSs which are capable of supporting decisions in critical situations where (1) making a decision entails knowing the states of some critical hypotheses, and such knowledge is acquired by performing suitable tests; (2) test outcomes are uncertain; (3) performing a test entails, in general, some drawbacks, so that a trade-off exists between such drawbacks and the value of the information provided by the test; (4) performing a test has the side-effect that it changes the expected benefit from performing other tests; (5) exceptional situations alter probability and utility default values. [source] From critical care to comfort care: the sustaining value of humourJOURNAL OF CLINICAL NURSING, Issue 8 2008Ruth Anne Kinsman Dean PhD Aims and objectives., To identify commonalities in the findings of two research studies on humour in diverse settings to illustrate the value of humour in team work and patient care, despite differing contexts. Background., Humour research in health care commonly identifies the value of humour for enabling communication, fostering relationships, easing tension and managing emotions. Other studies identify situations involving serious discussion, life-threatening circumstances and high anxiety as places where humour may not be appropriate. Our research demonstrates that humour is significant even where such circumstances are common place. Method., Clinical ethnography was the method for both studies. Each researcher conducted observational fieldwork in the cultural context of a healthcare setting, writing extensive fieldnotes after each period of observation. Additional data sources were informal conversations with patients and families and semi-structured interviews with members of the healthcare team. Data analysis involved line-by-line analysis of transcripts and fieldnotes with identification of codes and eventual collapse into categories and overarching themes. Results., Common themes from both studies included the value of humour for team work, emotion management and maintaining human connections. Humour served to enable co-operation, relieve tensions, develop emotional flexibility and to ,humanise' the healthcare experience for both caregivers and recipients of care. Conclusions., Humour is often considered trivial or unprofessional; this research verifies that it is neither. The value of humour resides, not in its capacity to alter physical reality, but in its capacity for affective or psychological change which enhances the humanity of an experience, for both care providers and recipients of care. Relevance to clinical practice., In the present era which emphasises technology, efficiency and outcomes, humour is crucial for promoting team relationships and for maintaining the human dimension of health care. Nurses should not be reluctant to use humour as a part of compassionate and personalised care, even in critical situations. [source] Strategic help in user interfaces for information retrievalJOURNAL OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE AND TECHNOLOGY, Issue 5 2002Giorgio Brajnik Although no unified definition of the concept of search strategy in Information Retrieval (IR) exists so far, its importance is manifest: nonexpert users, directly interacting with an IR system, apply a limited portfolio of simple actions; they do not know how to react in critical situations; and they often do not even realize that their difficulties are due to strategic problems. A user interface to an IR system should therefore provide some strategic help, focusing user's attention on strategic issues and providing tools to generate better strategies. Because neither the user nor the system can autonomously solve the information problem, but they complement each other, we propose a collaborative coaching approach, in which the two partners cooperate: the user retains the control of the session and the system provides suggestions. The effectiveness of the approach is demonstrated by a conceptual analysis, a prototype knowledge-based system named FIRE, and its evaluation through informal laboratory experiments. [source] A cognitive aid for neonatal resuscitation: a randomized controlled trialPEDIATRIC ANESTHESIA, Issue 7 2009M.D. Bould Introduction:, Anaesthetists are among several health care practitioners responsible for neonatal resuscitation in Canada. The Neonatal resuscitation program (NRP) courses are the North American educational standard. NRP has been shown to be an effective way of learning skills and knowledge but retention has been found to be problematic [1]. The use of cognitive aids is mandatory in industries such as aviation, to avoid dependence on memory when decision making in critical situations. Visual cognitive aids have been studied retrospectively in resuscitation and performance was found to correlate to the frequency of use of the aid [2]. Cognitive aids have been found to be of benefit in an unblinded prospective study [3]. We aimed to conduct the first blinded study on the effect of a cognitive aid on the performance of simulated resuscitation. Methods:, We conducted a single-blind randomized controlled trial to investigate whether the presence of a cognitive aid improved performance in a simulated neonatal resuscitation. After ethics board approval we recruited 32 anaesthesia residents who had previously passed the NRP. Subjects were randomized to an intervention group that had a poster detailing the NRP algorithm and a control group without the poster. The cognitive aid was positioned so that it could not be seen on the video recordings of the simulation that was used to assess performance. The scenario was piloted to confirm adequate blinding. Both groups had their performance in a simulated neonatal resuscitation recorded and subsequently analyzed by a peer, an expert anaesthetist and an expert neonatologist, using a previously validated checklist. A further rater observed the scenario in real time to examine frequency of use of the cognitive aid. Results:, The inter-rater reliability of the checklist was excellent with an intraclass correlation coefficient of 0.88. Consequently the mean of the scores assigned by all three raters was used for analysis. The median checklist score in the control group 18.2 [15.0,20.5 (10.7,25.3)] was not significantly different from that in the intervention group 20.3 [18.3,21.3 (15.0,24.3)] (P = 0.08). Retention of NRP skills and knowledge of was poor: when evaluated by the neonatologist none of the subjects correctly performed all life-saving interventions necessary to pass the checklist. Although only one subject in the intervention group did not use the aid at all, only 26.7% used the aid frequently and none used it extensively. Discussion:, Retention of skills after NRP training was poor. Our study confirms previous findings of poor retention of skills after NRP training: Kaczorowski et al. investigated family medicine trainees and found that none of 44 residents that were retested 6,8 months after an NRP course would have passed the course due to errors in life-saving interventions [1]. Previous research has shown that the presence of a cognitive aid can improve performance in the simulated management of a rare, high stakes scenario: malignant hyperthermia [3]. Our negative findings contrast with this and another previous study [2]. A potential reason for this discrepancy is that the raters in the previous studies were not blinded to group allocation, nor were the rating scales used validated. The infrequent use of the cognitive aid may be the reason that it did not improve performance in. Further research is required to investigate whether cognitive aids can be useful if their use is incorporated into NRP training. Conclusion:, A randomized single-blinded trial found that a cognitive aid did not improve performance at simulated resuscitation, in contrast to previous retrospective and unblended studies. Retention of skills and knowledge after resuscitation training remains an ongoing challenge for medical educators. [source] Statistical investigation of the nonlinear dynamical behavior of offshore structuresPROCEEDINGS IN APPLIED MATHEMATICS & MECHANICS, Issue 1 2008Jürgen Reimers The increasing amount of reports concerning damages of ships, structures and loss of cargo due to wave structure interaction demand the development of systems to predict critical situations in the offshore environment. Within the last years, research has been done to predict encounter with critical wave or wave groups such as "rogue waves" or the so,called "three sisters". The aim of such research is to develop programs that predict dangerous incidents and possibly alert the crew in time. The dangers of such extreme wave situations are severe, but occurrence of them is rather rare. Additionally and more often, structures are endangered because of fluid,structure,interaction leading to critical dynamical system behaviour in a wave environment that shows no extreme wave heights. The severeness of these incidents then depends on the experience and correctness of decision concerning the evasive actions of the master and his crew. Taking nonlinear effects into account, the statistical investigation of structures in waves shows critical behaviour of ships and structures without the absolute necessity of heavy sea conditions or the occurrence of dangerous sea phenomena. This paper describes the development of a program that uses a Monte,Carlo,Simulation technique based on a common panel,method for the creation of added masses and added dampings to predict the behaviour of the structure in several wave conditions. It shows possible ways to prevent the occurrence using similar early warning systems to those in development for critical wavegroups. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] 3-Fluoro-2,4-dioxa-3-phosphadecalins as Inhibitors of Acetylcholinesterase.CHEMISTRY & BIODIVERSITY, Issue 3 2009A Reappraisal of Kinetic Mechanisms, Diagnostic Methods Abstract A systematic survey of the acetylcholine-mimetic 2,4-dioxa-3-phosphadecalins as irreversible inhibitors of acetylcholinesterase revealed hitherto overlooked properties as far as the kinetic mechanisms of interaction are concerned. As a support to past and future work in this field, we describe the kinetics of eight reaction schemes that may be found in irreversible enzyme modification and compare them with two mechanism of reversible, slow-binding inhibition. The relevant kinetic equations and their associated graphical representations are given for all mechanisms, and concrete examples illustrate their practical use. Since irreversible inhibition is a time-dependent phenomenon, kinetic analysis is greatly facilitated by fitting the appropriate integrated rate equations to reaction-progress curves by nonlinear regression. This primary scrutiny provides kinetic parameters that are indispensable tools for diagnosing the kinetic mechanism and for calculating inhibition constants. Numerical integration of sets of differential equations is an additional useful investigation tool in critical situations, e.g., when inhibitors are unstable and/or act as irreversible modifiers only temporarily. [source] | ||||||||||||||||