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Patient Scenarios (patient + scenario)

Distribution by Scientific Domains

Medical Sciences	100%

Selected Abstracts

A new automated delineation method for SPECT lung scans using adaptive dual-exponential thresholding

INTERNATIONAL JOURNAL OF IMAGING SYSTEMS AND TECHNOLOGY, Issue 1 2007
Alex Wang
Abstract An accurate method for delineating lung contours in single photon emission computed tomography (SPECT) is critical to respiratory studies such as pulmonary embolism (PE) and respiratory aerosol deposition. Current delineation methods are not adaptive in nature and may require a priori information on lung volumes. We have developed a dual-exponential thresholding method that solely requires SPECT scans, and is fast, accurate, and adaptive in nature. A dataset consisted of 90 patients was studied retrospectively. While most were suspected of PE, other pulmonary disorders were also present. SPECT ventilation scans were obtained after inhalation of ,40 MBq of 99mTc-Technegas. Examination of the corresponding natural logarithmically transformed histograms revealed dual exponential functions like pattern. Adaptive thresholds were found as the intercept between the two exponential functions. 350 Monte Carlo simulations representative of normally-ventilated scans with varying counts were used to quantitatively measure and evaluate the method. Our method correctly delineated lung volumes to above 97% agreement for 310 of the 350 Monte Carlo simulations with maximum count values greater than or equal to 31. The 40 low-count simulations were included purely as extreme cases. For real patient scenario, an experienced physician was called upon to visually delineate a sample of 50 actual patient scans, and these delineated lung volumes were used as gold standard and compared with those delineated using our method. Our results had an average of 96% agreement. © 2007 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 17, 22,27, 2007 [source]

Integrating the Principles of Evidence-Based Practice Into Clinical Practice

JOURNAL OF THE AMERICAN ACADEMY OF NURSE PRACTITIONERS, Issue 3 2004
Kathleen A. Klardie RN
Column Editor Comment This series of articles illustrates many considerations relevant to the application of clinical practice guidelines (CPGs). This particular column describes the actions of a nurse practitioner (NP) striving to understand the foundations of recommendations that are based largely on expert opinion. Although application of CPGs does not generally require this degree of investigation, it is essential that providers understand the processes used to interpret the basis of recommendations, including the application of the basic statistical concepts, when making decisions about how recommendations apply to individual patient scenarios. Utilizing evidence-based practice when providing patient care requires a range of skills that allows the NP to locate appropriate research evidence, to develop an understanding of the statistics used in interpreting and reporting research, and to evaluate the effects of interventions on patient outcomes. The application of the key concepts of evidenced-based practice within the primary care setting is explored through a hypothetical patient scenario, which was created as the focal point for three articles that illustrate principles of evidence-based practice. The goal of this series of articles is to provide a basic understanding of evidence-based practice and its application in clinical practice. This article explores the use of interventions selected from CPGs and investigates the potential effects of recommended interventions on patient outcomes. Commonly encountered statistical concepts are reviewed, and examples of their application in interpreting and reporting research are demonstrated. The principles of relative risk, relative risk reduction, absolute risk reduction, and numbers needed to treat are described. This review provides the NP with some basic skills to determine both the quality and usefulness of research. [source]

Secondary prevention of ischemic stroke: Challenging patient scenarios,

JOURNAL OF HOSPITAL MEDICINE, Issue S4 2008
Kiwon Lee MD
Abstract The risk for recurrent stroke following a stroke or transient ischemic attack (TIA) is high. Prevention of a secondary event is a priority, as the associated morbidity and mortality are great. Antiplatelet agents have been shown to reduce this risk, but the choice of treatment modality depends on a number of factors, including the underlying cause of the stroke and the patient's comorbidities. For example, a cardioembolic stroke is best treated with anticoagulants, whereas one of noncardioembolic origin requires antiplatelet therapy. A number of challenging patient scenarios are explored in this article, and appropriate medical management is discussed, with the goal of examining the most recent trial data and information in the context of an actual case. Eight sample cases are presented: stroke prevention in a patient with recent stent placement, low ejection fraction, intracranial stenosis, carotid stenosis, atherosclerosis of the aortic arch, symptomatic coronary artery disease, antiplatelet failure, and stroke prevention in a patient already on warfarin. Journal of Hospital Medicine 2008;3(4 Suppl):S20,S28. © 2008 Society of Hospital Medicine. [source]

Integrating the Principles of Evidence-Based Practice Into Clinical Practice

Structured assessment using multiple patient scenarios by videoconference in rural settings

MEDICAL EDUCATION, Issue 5 2008
Tim J Wilkinson
Context, The assessment blueprint of the Australian College of Rural and Remote Medicine postgraduate curriculum highlighted a need to assess clinical reasoning. We describe the development, reliability, feasibility, validity and educational impact of an 8-station assessment tool, StAMPS (structured assessment using multiple patient scenarios), conducted by videoconference. Methods, StAMPS asks each candidate to be examined at each of 8 stations on issues relating to patient diagnosis or management. Each candidate remains located in a rural site but is examined in turn by 8 examiners who are located at a central site. Examiners were rotated through the candidates by either walking between videoconference rooms or by connecting and disconnecting the links. Reliability was evaluated using generalisability theory. Validity and educational impact were evaluated with qualitative interviews. Results, Fourteen candidates were assessed on 82 scenarios with a reliability of G = 0.76. There was a reasonable correlation with level of candidate expertise (, = 0.57). The videoconference links were acceptable to candidates and examiners but the walking rotation system was more reliable. Qualitative comments confirmed relevance and acceptability of the assessment tool and suggest it is likely to have a desirable educational impact. Conclusions, StAMPS not only reflects the content of rural and remote practice but also reflects the process of that work in that it is delivered from a distance and assesses resourcefulness and flexibility in thinking. The reliability and feasibility of this type of assessment has implications for people running any distance-based course, but the assessment could also be used in a face-to-face setting. [source]