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41.
Anderson DJ Hartwig MG Pappas T Sexton DJ Kanafani ZA Auten G Kaye KS 《Annals of surgery》2008,247(2):343-349
OBJECTIVE: To determine if surgical volume affects the risk of surgical site infections (SSI) in community hospitals. BACKGROUND: The utility of public reporting and the optimal methods to employ when reporting SSI rates remain controversial and contentious issues. Studies examining the association between surgical volume and SSI risk have included few community hospitals and have reported conflicting results. METHODS: A prospective study of surgical procedures performed at 18 community hospitals from January 1, 2004 to December 31, 2005, was performed. Hospitals were separated based on average surgical volume per year: small (<1500 procedures), medium (1500 < or = procedures < 4000), and large (> or =4000 procedures). The risk of SSI for each category was determined using multivariable Poisson regression. RESULTS: Prospective surveillance identified 1434 SSIs after 132,111 surgical procedures (prevalence rate = 1.09/100 procedures). In unadjusted analysis, the risk of SSI was almost twice as high at small hospitals [prevalence rate ratio (PRR) = 1.9 (95% CI 1.78-2.05)] and large hospitals [PRR = 1.79 (95% CI 1.70-1.90)] compared with medium hospitals. After adjusting for differences between hospital category and important confounders, the risk of SSI at small hospitals was still 1.5 times higher than medium hospitals [adjusted PRR = 1.49 (95% CI 1.39-1.60)], whereas the risk at large hospitals was substantially decreased compared with medium hospitals [adjusted PRR = 1.29 (95% CI 1.22-1.36)]. OUTCOMES: The relationship between hospital surgical volume and rates of SSI in community hospitals is important and complex. As public reporting of SSI rates expands, improved methods for risk-adjusting infection rates are needed. 相似文献
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43.
Michael J. Blaha Seamus P. Whelton Mahmoud Al Rifai Zeina A. Dardari Leslee J. Shaw Mouaz H. Al-Mallah Kuni Matsushita John A. Rumberger Daniel S. Berman Matthew J. Budoff Michael D. Miedema Khurram Nasir 《Journal of Cardiovascular Computed Tomography》2017,11(1):54-61
Background
Although coronary artery calcium (CAC) has been investigated for over two decades, there is very limited data on the association of CAC with cause of death. The CAC Consortium is a large ongoing multi-center observational cohort of individuals who underwent non-contrast cardiac-gated CAC testing and systematic, prospective, long-term follow-up for mortality with ascertainment of cause of death.Methods
Four participating institutions from three states within the US (California, Minnesota, and Ohio) have contributed individual-level patient data to the CAC Consortium (spanning years 1991–2010). All CAC scans were clinically indicated and physician-referred in patients without a known history of coronary heart disease. Using strict inclusion and exclusion criteria to minimize missing data and to eliminate non-dedicated CAC scans (i.e. concomitant CT angiography), a sharply defined and well-characterized cohort of 66,636 patients was assembled. Mortality status was ascertained using the Social Security Administration Death Master File and a validated algorithm. In addition, death certificates were obtained from the National Death Index and categorized using ICD (International Classification of Diseases) codes into common causes of death.Results
Mean patient age was 54 ± 11 years and the majority were male (67%). Prevalence of CVD risk factors was similar across sites and 55% had a <5% estimated 10-year atherosclerotic cardiovascular disease (ASCVD) risk. Approximately 45% had a Calcium score of 0 and 11% had an Agatston Score ≥400. Over a mean follow-up of 12 ± 4 years, there were 3158 deaths (4.15 per 1000 person-years). The majority of deaths were due to cancer (37%) and CVD (32%). Most CVD deaths were due to CHD (54%) followed by stroke (17%). In general, CAC score distributions were similar across sites, and there were similar cause of death patterns.Conclusions
The CAC Consortium is large and highly generalizable data set that is uniquely positioned to expand the understanding of CAC as a predictor of mortality risk across the spectrum of disease states, allowing innovative modeling of the competing risks of cardiovascular and non-cardiovascular death. 相似文献44.
45.
Sleilaty G Yazigi A El Asmar B Hajj-Chahine J Nakad J Madi-Jebara S Aoun-Bacha Z Badaoui G 《Le Journal médical libanais. The Lebanese medical journal》2007,55(2):101-103
Cardiac surgery in patients with previous pneumonectomy is infrequently reported. We report a case of combined coronary artery bypass grafting and aortic valve replacement in a patient with left ventricular ejection fraction less then 35% and a previous right pneumonectomy. All steps in operative management of this rare condition are discussed. 相似文献
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47.
Foudda R. Homsy Mutlu Özcan Marwan Khoury Zeina A.K. Majzoub 《The Journal of prosthetic dentistry》2018,119(5):783-790
Statement of problem
The subtractive and additive computer-aided design and computer-aided manufacturing (CAD-CAM) of lithium disilicate partial coverage restorations is poorly documented.Purpose
The purpose of this in vitro study was to compare the marginal and internal fit accuracy of lithium disilicate glass-ceramic inlays fabricated with conventional, milled, and 3-dimensional (3D) printed wax patterns.Material and methods
A dentoform mandibular first molar was prepared for a mesio-occlusal ceramic inlay. Five groups of 15 inlays were obtained through conventional impression and manual wax pattern (group CICW); conventional impression, laboratory scanning of the stone die, CAD-CAM milled wax blanks (group CIDW) or 3D printed wax patterns (group CI3DW); and scanning of the master preparation with intraoral scanner and CAD-CAM milled (group DSDW) or 3D printed wax patterns (group DS3DW). The same design was used to produce the wax patterns in the last 4 groups. The replica technique was used to measure marginal and internal adaptation by using stereomicroscopy. Mixed-model ANOVA was used to assess differences according to the groups and discrepancy location (α=.05).Results
Group DSDW showed the smallest marginal discrepancy (24.3 μm) compared with those of groups CICW (45.1 μm), CIDW (33.7 μm), CI3DW (39.8 μm), and DS3DW (39.7 μm) (P<.001). No statistically significant differences were detected among groups CICW, CIDW, CI3DW, and DS3DW relative to the marginal discrepancy. The internal discrepancy was significantly larger than the marginal discrepancy within all groups (P<.001).Conclusions
Lithium disilicate glass-ceramic inlays produced from digital scans and subtractive milling of wax patterns resulted in better marginal and internal fit accuracy than either conventional impression/fabrication or additive 3D manufacturing. Three-dimensional printed wax patterns yielded fit values similar to those of the conventionally waxed inlays. 相似文献48.
Kocken PL Eeuwijk J Van Kesteren NM Dusseldorp E Buijs G Bassa-Dafesh Z Snel J 《The Journal of school health》2012,82(3):115-122
BACKGROUND: Vending machines account for food sales and revenue in schools. We examined 3 strategies for promoting the sale of lower‐calorie food products from vending machines in high schools in the Netherlands. METHODS: A school‐based randomized controlled trial was conducted in 13 experimental schools and 15 control schools. Three strategies were tested within each experimental school: increasing the availability of lower‐calorie products in vending machines, labeling products, and reducing the price of lower‐calorie products. The experimental schools introduced the strategies in 3 consecutive phases, with phase 3 incorporating all 3 strategies. The control schools remained the same. The sales volumes from the vending machines were registered. Products were grouped into (1) extra foods containing empty calories, for example, candies and potato chips, (2) nutrient‐rich basic foods, and (3) beverages. They were also divided into favorable, moderately unfavorable, and unfavorable products. RESULTS: Total sales volumes for experimental and control schools did not differ significantly for the extra and beverage products. Proportionally, the higher availability of lower‐calorie extra products in the experimental schools led to higher sales of moderately unfavorable extra products than in the control schools, and to higher sales of favorable extra products in experimental schools where students have to stay during breaks. Together, availability, labeling, and price reduction raised the proportional sales of favorable beverages. CONCLUSION: Results indicate that when the availability of lower‐calorie foods is increased and is also combined with labeling and reduced prices, students make healthier choices without buying more or fewer products from school vending machines. Changes to school vending machines help to create a healthy school environment. 相似文献
49.
Lupo PJ Langlois PH Reefhuis J Lawson CC Symanski E Desrosiers TA Khodr ZG Agopian AJ Waters MA Duwe KN Finnell RH Mitchell LE Moore CA Romitti PA Shaw GM;National Birth Defects Prevention Study 《Environmental health perspectives》2012,120(6):910-915
Background: Exposure to polycyclic aromatic hydrocarbons (PAHs) occurs in many occupational settings. There is evidence in animal models that maternal exposure to PAHs during pregnancy is associated with gastroschisis in offspring; however, to our knowledge, no human studies examining this association have been conducted.Objective: Our goal was to conduct a case–control study assessing the association between estimated maternal occupational exposure to PAHs and gastroschisis in offspring.Methods: Data from gastroschisis cases and control infants were obtained from the population-based National Birth Defects Prevention Study for the period 1997–2002. Exposure to PAHs was assigned by industrial hygienist consensus, based on self-reported maternal occupational histories from 1 month before conception through the third month of pregnancy. Logistic regression was used to determine the association between estimated occupational PAH exposure and gastroschisis among children whose mothers were employed for at least 1 month during the month before conception through the third month of pregnancy.Results: The prevalence of estimated occupational PAH exposure was 9.0% in case mothers (27 of 299) and 3.6% in control mothers (107 of 2,993). Logistic regression analyses indicated a significant association between occupational PAHs and gastroschisis among mothers ≥ 20 years of age [odds ratio (OR) = 2.53; 95% confidence interval (CI): 1.27, 5.04] after adjusting for maternal body mass index, education, gestational diabetes, and smoking. This association was not seen in mothers < 20 years (OR = 1.14; 95% CI: 0.55, 2.33), which is notable because although young maternal age is the strongest known risk factor for gastroschisis, most cases are born to mothers ≥ 20 years.Conclusion: Our findings indicate an association between occupational exposure to PAHs among mothers who are ≥ 20 years and gastroschisis. These results contribute to a body of evidence that PAHs may be teratogenic. 相似文献
50.
Marie-Hélène Gannagé-Yared Chirine Farès Tony Ibrahim Zeina Abou Rahal Michele Elias Dania Chelala 《Metabolism: clinical and experimental》2013