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Chu‐Lin Tsai MD MPH Justin A. Sobrino BS Carlos A. Camargo Jr MD DrPH 《Academic emergency medicine》2008,15(12):1275-1283
Objectives: Little is known about recent trends in U.S. emergency department (ED) visits for acute exacerbation of chronic obstructive pulmonary disease (AECOPD) or about ED management of AECOPD. This study aimed to describe the epidemiology of ED visits for AECOPD and to evaluate concordance with guideline‐recommended care. Methods: Data were obtained from National Hospital Ambulatory Medical Care Survey (NHAMCS). ED visits for AECOPD, during 1993 to 2005, were identified using the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD‐9‐CM) codes. Concordance with guideline recommendations was evaluated using process measures. Results: Over the 13‐year study period, there was an average annual 0.6 million ED visits for AECOPD, and the visit rates for AECOPD were consistently high (3.2 per 1,000 U.S. population; Ptrend = 0.13). The trends in the use of chest radiograph, pulse oximetry, or bronchodilator remained stable (all Ptrend > 0.5). By contrast, the use of systemic corticosteroids increased from 29% in 1993–1994 to 60% in 2005, antibiotics increased from 14% to 42%, and methylxanthines decreased from 15% to <1% (all Ptrend < 0.001). Multivariable analysis showed patients in the South (vs. the Northeast) were less likely to receive systemic corticosteroids (odds ratio [OR] = 0.6; 95% confidence interval [CI] = 0.4 to 0.9). Conclusions: The high burden of ED visits for AECOPD persisted. Overall concordance with guideline‐recommended care for AECOPD was moderate, and some emergency treatments had improved over time. 相似文献
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Knut E Kj?rstad Dag Ole Nordhaug Christian Korvald Stig Müller Tor Steensrud Truls Myrmel 《European journal of cardio-thoracic surgery》2007,31(4):677-684
OBJECTIVE: The time constant of mechanical restitution (T((MRC))), proposed to reflect changes in calcium release and uptake, has been shown to increase in left ventricular (LV) failure, and might have a potential as an index of contractile function. However, in vivo studies of the effect on T((MRC)) of changing loading conditions in the normal and failing heart have not been reported. Consequently, in this study, we tested the hypothesis that the increase in T((MRC)) in vivo is independent of preload and afterload. METHODS: Left ventricular pressure-volume loops were assessed at baseline in eight open chest pigs using the combined pressure-volume conductance catheter technique during right atrial pacing at 120b/min. Mechanical restitution curves (MRC) were constructed during four different loading conditions in all eight animals: uninfluenced load, reduced preload (balloon catheter in v. cava inferior), increased afterload (balloon catheter in descending aorta), and increased preload combined with reduced afterload (aortocaval shunting). Acute LV failure was then induced by microembolization through the left main coronary artery, and the experimental protocol was repeated. Contractile response was defined as the maximal first derivative of pressure (dP/dt(max)), and T((MRC)) was calculated using a least square approximation algorithm. RESULTS: Hemodynamic data 30min after microembolization showed decreased mean arterial pressure (98+/-14-67+/-10mmHg, (mean+/-SD) P<0.0001) and dP/dt(max) (1482+/-193-1001+/-125mmHg/s, P=0.001). Stroke volume decreased from 30+/-5 to 20+/-5ml (P<0.0001) compared to baseline, and preload recruitable stroke work decreased from 52+/-7 to 31+/-10mmHg (P=0.002). T((MRC)) increased in all eight animals after induction of LV failure at all loading conditions. There was no difference between the different loading conditions at baseline, nor at LV heart failure, but T((MRC)) increased significantly after the induction of heart failure (ANOVA, two ways). CONCLUSIONS: We have shown that the left ventricular T((MRC)) increases after developed heart failure. The increase in T((MRC)) was independent on loading conditions and thus have a potential for a contractility index. 相似文献
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LISA HARNACK DrPH RD GLADYS BLOCK PHD AMY SUBAR PhD RD SYLVIA LANE PhD RICHARD BRAND PhD 《Journal of the American Dietetic Association》1997,97(9):957-965
Objective To examine the relationship of cancer prevention-related nutrition knowledge, beliefs, and attitudes to cancer prevention dietary behavior.Subjects/setting Noninstitutionalized US adults aged 18 years and older.Methods Data collected in the 1992 National Health Interview Survey Cancer Epidemiology Supplement were analyzed. The supplement included questions to ascertain knowledge, beliefs, and attitudes and a food frequency questionnaire to ascertain nutrient intake.Statistics Multivariate linear regression modeling was conducted to assess the hypothesized relationships.Results After adjustment for relevant covariates (age, sex, education, total energy, perceived barriers to eating a more healthful diet), knowledge and belief constructs were predictive of dietary behavior. Specifically, fat, fiber, and fruit and vegetable intakes more closely approximated dietary recommendations for persons with more cancer-prevention knowledge. The strength of the associations between these constructs and dietary behavior varied in some cases according to level of education and perceived barriers to eating a healthful diet. Of the perceived barriers to eating a healthful diet, perceived ease of eating a healthful diet was most strongly and consistently predictive of intake.Conclusions Research findings challenge dietetics practitioners to design diet- and health-promotion programs and activities that not only educate the public about the importance of diet to health, but also address barriers to dietary change. 相似文献
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Abstract: Spontaneous intracranial hypotension (SIH) is a postural headache syndrome unrelated to dural puncture. Because of the increasing failure of epidural blood patch (EBP) to relieve headache in SIH, we retrospectively investigated the epidemiological features and treatment outcomes in 55 cases of SIH. The study population was stratified by age and sex; continuous variables were compared for differences by t -tests; categorical variables were compared by Chi-squared analysis or Fisher exact tests. Significant differences were identified by P values of 0.05 or less. The mean age of the study population was 44 ± 12 years with a female to male ratio of 1.3:1.0. Men presented with subdural hematomas ( P = 0.001) more often than women. Meningeal enhancement on contrast magnetic resonance imaging (MRI) was the most consistent radiographic finding. Radionuclide cisternography (RC) demonstrated thoracolumbar dural leaks in 16 of 22 patients. EBP failures were more common in patients aged 40 and younger than in older patients ( P = 0.003). Postural headache from SIH was not uniformly responsive to EBP, and had significant comorbidities, especially in men. The management of postural headache in SIH by other techniques to restore brain position and cerebrospinal fluid dynamics should be investigated. 相似文献
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