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STUDY OBJECTIVES: Use of fast track has been shown to improve the emergency department flow of less urgent patients. It has been speculated, however, that this could negatively affect the care of urgent patients. The objective of this study was to determine whether a dedicated fast track for less urgent patients [Canadian Triage and Acuity scale category 4/5 (CTAS 4/5)] affected (1) the time to assessment for urgent patients (CTAS 3), (2) the length of stay for less urgent patients (CTAS 4 and 5), and (3) the left-without-being-seen rate. METHODS: In June 2003, fast track was opened in our emergency department from 13:00 to 19:00 h. A before-after intervention comparison analysis was completed for 1 week in Aug 2002 and the same week in Aug 2003. Data collected included (1) time to assessment of CTAS 3 patients, (2) the length of stay for CTAS 4/5 patients, and (3) percentage of patients who left without being seen. RESULTS: A total of 368 patients were reviewed for 2002 and 380 patients were reviewed for 2003. Median time to assessment of CTAS 3 patients presenting from 13:00 to 19:00 h was reduced from 66 min (Interquartile range: 40, 94 min) in 2002 to 60 min (IQR: 38, 108 min) after fast track was open in 2003 (P = 0.95). Median length of stay of CTAS 4 and 5 patients was reduced from 170 min (IQR: 111, 256 min) to 110 min (IQR: 69, 185 min) (P < 0.001). The overall left-without-being-seen rate decreased from 5% (20/368) to 2% (9/380). CONCLUSION: A dedicated fast track for CTAS 4/5 patients can reduce the length of stay and the left-without-being-seen rate with no impact on CTAS 3 patients seen in the main emergency department.  相似文献   
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Agenesis of the Gallbladder Revisited Laparoscopically   总被引:1,自引:0,他引:1  
Gallbladder agenesis is an extremely rare disease. Necropsy incidence has been reported to be 0.016%. Failure lo locate the gallbladder at the time of a planned cholecystectomy can be very challenging. We report such a case during a laparoscopic cholecystectomy. The indication for surgery in these patients are complaints of gallbladder symptoms along with a false-positive ultrasound study. During exploration, an abnormal location of the gallbladder has to be excluded. Ectopic gallbladder locations include intrahepatic, lesser omentum, retroperitoneal, retrohepatic, within the falciform ligament, retroduodenal, and retrohepatic areas. Thorough exploration and cholangiography are essential. Embryologically, the gallbladder and cystic duct arise from the caudal portion of the hepatic bud. All of the previously reported cases of gallbladder agenesis have shown an absence of both the gallbladder and cystic duct. We report an embryological oddity wherein a patent cystic duct was found along with an agenetic gallbladder. This is the first case report of this finding, along with this being the first absent gallbladder discovered laparoscopically.  相似文献   
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Objective: The study goal was to compare the laser spot size created using reflective and refractive micromanipulators with a CO2 laser and to determine the sensitivity of spot size to laser power. Study Design and Setting: A CO2 laser and operating microscope (400-mm focal length) was coupled to either a reflective (Cassegrain-like) or refractive micromanipulator. Laser spot size was determined by measuring the region of ablation created by laser irradiation of wood (dry tongue depressors), exposed photographic film, and agar gel using optical micrometry. Laser power varied from 0.5 to 20 W with pulse durations of 0.1 and 0.5 second. Results: The reflective micromanipulator demonstrated overall smaller spot sizes for a given laser power and lower incremental change in spot size with increasing power. The reflective design demonstrated less sensitivity to increases in laser power. Conclusions: Micromanipulator optical design can result in significant differences in laser spot size. The reflective device used in this study demonstrated less sensitivity to increasing laser power. (Otolaryngol Head Neck Surg 2002;126:593-597.)  相似文献   
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Psoriasis is a chronic inflammatory condition that often requires life-long treatment. Conventional therapies have not fully met the needs of psoriatic patients, because of limited efficacy, adverse effects with cumulative use, and patient inconvenience. In the past decade, biologic immunotherapies have become accepted treatments for psoriasis as a result of perceived efficacy and safety on the part of patients and practitioners. However, most data on these medications come from relatively limited short-term trials. In this review, we will focus on the available long-term data on the efficacy of the biologic agents. We will emphasize the strengths and weakness of the available data of the biologic agents that are Food and Drug Administration (FDA)-approved for the treatment of moderate to severe psoriasis (alefacept, efalizumab, * etanercept, infliximab, and adalimumab), with the inclusion of a newer agent currently under FDA evaluation (ustekinumab).  相似文献   
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Few cases in the history of epidemiology and public health are more famous than John Snow's investigation of a neighborhood cholera outbreak in the St. James, Westminster, area of London in 1854. In this study Snow is assumed to have proven that cholera was water rather than airborne through a methodology that became, and to a great extent remains, central to the science and social science of disease studies. And yet, Snow's work did not satisfy most of his contemporaries who considered his proof of a solely waterborne cholera interesting but unconvincing. Uniquely, this paper asks whether the caution of Snow's contemporaries was reasonable, and secondly, whether Snow might have been more convincing within the science of the day. The answers significantly alter our understanding of this paradigmatic case. It does so in a manner offering insights both into the origins of nineteenth century disease analysis and more generally, the relation of mapping in the investigation of an outbreak of uncertain origin. The result has general relevance—pedagogically and practically—in epidemiology, medical geography, and public health.  相似文献   
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