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131.
OBJECTIVE: Our objective was to quantify incremental risk associated with transfusion of packed red blood cells and other blood components on morbidity after coronary artery bypass grafting. DESIGN: The study design was an observational cohort study. SETTING: This investigation took place at a large tertiary care referral center. PATIENTS: A total of 11,963 patients who underwent isolated coronary artery bypass from January 1, 1995, through July 1, 2002. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Among the 11,963 patients who underwent isolated coronary artery bypass grafting, 5,814 (48.6%) were transfused. Risk-adjusted probability of developing in-hospital mortality and morbidity as a function of red blood cell and blood-component transfusion was modeled using logistic regression. Transfusion of red blood cells was associated with a risk-adjusted increased risk for every postoperative morbid event: mortality (odds ratio [OR], 1.77; 95% confidence interval [CI], 1.67-1.87; p<.0001), renal failure (OR, 2.06; 95% CI, 1.87-2.27; p<.0001), prolonged ventilatory support (OR, 1.79; 95% CI, 1.72-1.86; p<.0001), serious infection (OR, 1.76; 95% CI, 1.68-1.84; p<.0001), cardiac complications (OR, 1.55; 95% CI, 1.47-1.63; p<.0001), and neurologic events (OR, 1.37; 95% CI, 1.30-1.44; p<.0001). CONCLUSIONS: Perioperative red blood cell transfusion is the single factor most reliably associated with increased risk of postoperative morbid events after isolated coronary artery bypass grafting. Each unit of red cells transfused is associated with incrementally increased risk for adverse outcome.  相似文献   
132.
Tricuspid regurgitation (TR) is a frequent complication after heart transplantation. The etiology of TR is multifactorial, but biopsy-induced flail leaflet is one of the most important mechanisms. A 61-year-old woman underwent heart transplant, but experienced several rejection episodes which required multiple surveillance endomyocardial biopsies. At three months after transplant, she required tricuspid valve repair due to symptomatic severe TR. The anterior leaflet was flail, with rupture of primary and secondary chordae. Valve repair was performed with a triple leaflet edge-to-edge technique. The procedure consisted of suture fixation of the prolapsed anterior leaflet joining to the septal and posterior leaflets, and placement of a 30-mm annuloplasty ring. The patient was uneventfully discharged home on day 7 with trivial TR. At a four-years post-transplant evaluation, she was in NYHA functional class I, with preserved ventricular function and trivial TR. She has been followed closely because of post-transplant coronary artery disease.  相似文献   
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134.
Knowledge of the clinical and economic impact of antimicrobial resistance is useful to influence programs and behavior in healthcare facilities, to guide policy makers and funding agencies, to define the prognosis of individual patients and to stimulate interest in developing new antimicrobial agents and therapies. There are a variety of important issues that must be considered when designing or interpreting studies into the clinical and economic outcomes associated with antimicrobial resistance. One of the most misunderstood issues is how to measure cost appropriately. Although imperfect, existing data show that there is an association between antimicrobial resistance in Staphylococcus aureus, enterococci and Gram-negative bacilli and increases in mortality, morbidity, length of hospitalization and cost of healthcare. Patients with infections due to antimicrobial-resistant organisms have higher costs (US $6,000-30,000) than do patients with infections due to antimicrobial-susceptible organisms; the difference in cost is even greater when patients infected with antimicrobial-resistant organisms are compared with patients without infection. Given limited budgets, knowledge of the clinical and economic impact of antibiotic-resistant bacterial infections, coupled with the benefits of specific interventions targeted to reduce these infections, will allow for optimal control and improved patient safety. In this review, the authors discuss a variety of important issues that must be considered when designing or interpreting studies of the clinical and economic outcomes associated with antimicrobial resistance. Representative literature is reviewed regarding the associations between antimicrobial resistance in specific pathogens and adverse outcomes, including increased mortality, length of hospital stay and cost.  相似文献   
135.
The purpose of this study was to assess the value of double contrast-enhanced ultrasound (DCUS), in which intravenous microbubbles are used together with an oral contrast agent as a method to evaluate the microvascular density (MVD) of gastric cancer, and its relationship with the contrast-enhanced intensity (EI) in gastric carcinomas. Sixty-nine patients with gastric cancer were examined preoperatively using DCUS. The arrival time (AT), time-to-peak (TTP), peak (PI) and baseline (pre-injection) intensities (BI) of gastric carcinoma and normal gastric wall were measured. Contrast-enhanced intensity (PI minus BI) was calculated. A monoclonal antibody against CD34 was used to display vascular endothelial cells in the resected gastric carcinoma specimens and in normal gastric mucosal tissues, and MVD was calculated by counting CD34-positive vascular endothelial cells. The differences in AT, TTP, EI and MVD between gastric carcinoma specimens and normal gastric wall tissues were evaluated using Student's t-test. The relationships between EI and MVD in gastric cancer were analyzed by Spearman rank correlation analysis. Both EI and MVD were significantly higher in gastric carcinomas than in normal gastric wall (p < 0.001). However, AT and TTP showed no significant differences between gastric carcinoma specimens and normal gastric wall tissues (p > 0.05). There was a strong positive linear correlation between EI and MVD in gastric carcinoma (r = 0.921, p < 0.001). Double contrast-enhanced ultrasound is a useful method for evaluation of the MVD in gastric carcinomas in vivo. Contrast-enhanced intensity has a strong positive linear correlation with MVD and could form a new index for assessing angiogenesis and the biological behavior of gastric carcinomas. (E-mail: huangpintong@126.com)  相似文献   
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BACKGROUND: This study evaluated the clinical and economic impact of the emergence of third-generation cephalosporin-resistant Enterobacter species. METHODS: Mortality, length of hospitalization, and hospital charges were examined in a cohort that was selected from a group of 477 patients with initial cultures that yielded a third-generation cephalosporin-susceptible Enterobacter species. Case patients (n = 46) had subsequent cultures yielding a third-generation cephalosporin-resistant Enterobacter species. Control patients (n = 113) who did not develop resistance were matched to cases on site of Enterobacter infection and length of hospitalization prior to isolation of the initial susceptible organism. Multivariable analyses were used to adjust for confounding. RESULTS: Twenty-six percent of cases died vs 13% of controls (P =.06). The median total hospital stay for cases was 29.5 days (interquartile range [IQR], 20-60) and 19 days for controls (IQR, 13-27; P<.001). The median hospital charge for cases was $79 323 (IQR, $34 546-$161 384) and for controls was $40 406 (IQR, $18 470-$79 005; P<.001). After adjusting for comorbidities, severity of illness, intensive care unit admission, surgery, transfer from another hospital, sex, and age, emergence of resistance was associated with increased mortality (relative risk, 5.02; P =.01), hospital stay (1.5-fold, P<.001), and hospital charges (1.5-fold, P<.001). Emergence of resistance had a median attributable hospital stay of 9 days and an average attributable hospital charge of $29 379. CONCLUSIONS: Emergence of antibiotic resistance in Enterobacter species results in increased mortality, hospital stay, and hospital charges. Minimizing resistance in Enterobacter species should be a priority.  相似文献   
138.
Background Randomized trials comparing multivessel stenting with coronary artery bypass surgery (CABG) have demonstrated similar rates of death and myocardial infarction but higher rates of repeat revascularization after stenting. The impact of these alternative strategies on overall medical care costs is uncertain, particularly within the US health care system. Methods We performed a retrospective, matched cohort study to compare the clinical and economic outcomes of multivessel stenting and bypass surgery. The stent group consisted of 100 consecutive patients who underwent stenting of ≥2 major native coronary arteries at our institution. The CABG group consisted of 200 patients who underwent nonemergent isolated bypass surgery during the same time frame, matched (2:1) for age, sex, ejection fraction, diabetes mellitus, and extent of coronary disease. Detailed clinical follow-up and resource utilization data were collected for a minimum of 2 years. Total costs were calculated by use of year 2000 unit prices. Results Over a median follow up period of 2.8 years, there were no significant differences in all-cause mortality rates (3.0% vs 3.0%), Q-wave myocardial infarction (5.1% vs 4.0%), or the composite of death or myocardial infarction (7.1% vs 7.0%) between the stent and CABG groups (P = not significant for all comparisons). However, at 2-year follow up, patients with stents were more likely to require ≥1 repeat revascularization procedure (32.0% vs 4.5%, P < .001). The initial cost of multivessel stenting was 43% less than the cost of CABG ($11,810 vs $20,574, P < .001) and remained 27% less ($17,634 vs $24,288, P = .005) at 2 years. Conclusions Multivessel stenting and CABG result in comparable risks of death and myocardial infarction. Despite a higher rate of repeat revascularization, multivessel stenting was significantly less costly than CABG through the first 2 years of follow-up. (Am Heart J 2003;145:334-42.)  相似文献   
139.
It is clear that the widespread and injudicious use of antimicrobials has greatly increased the presence of MDROs that threaten the health of all. There is worldwide acknowledgement that this threat is growing, and that prudent use of antimicrobials combined with infection prevention can prevent harm and improve patient safety. Antimicrobial stewardship programs must harness the talents of all members of the health care team to effectively identify the organism, determine its susceptibility, institute any precautions required, and prescribe the narrowest-acting antibiotic that will destroy it. IPs/HEs play a pivotal role in this approach, by assisting with early organism and infected patient identification, by promoting compliance with standard and transmission-based precautions and other infection prevention strategies such as care bundle practices, hand hygiene, and by educating staff, patients, and visitors.  相似文献   
140.
There is increasing evidence that kappa-opioid receptor agonists modulate cocaine-maintained behavior, and limited findings implicate the involvement of kappa-opioid receptors in ethanol-maintained behaviors. The purpose of the present study was to investigate the effects of bremazocine, a kappa-opioid agonist, on the self-administration of smoked cocaine base and oral ethanol in rhesus monkeys (Macaca mulatta). To determine the selectivity of bremazocine, the effects of bremazocine pretreatment on the oral self-administration of phencyclidine (PCP), saccharin, and food were also examined. Adult male rhesus monkeys were trained to self-administer oral ethanol, PCP, saccharin (n = 8), food (n = 6), or smoked cocaine base (n = 6) and water during daily sessions. Bremazocine (0.00032-, 0.001-, and 0.0025-mg/kg i.m.) injections were given 15 min before session. The 4 days of stable behavior before pretreatment served as baseline. Demand curves (consumption x fixed ratio; FR) were obtained for smoked cocaine base, ethanol, and PCP by varying the cost (FR) of drug deliveries and measuring consumption (deliveries). Bremazocine (0.001 mg/kg) was administered at each FR value in nonsystematic order. Results indicate that bremazocine dose dependently reduced cocaine, ethanol, PCP, and saccharin intake. Food intake was affected less by bremazocine than the other substances in five of the six monkeys. Generally, bremazocine treatment reduced the demand for cocaine, ethanol, and PCP as well as other measures of response strength. These results extend the findings that kappa-agonists reduce the self-administration of drug and nondrug reinforcers to smoked cocaine base and oral ethanol, PCP, and saccharin in rhesus monkeys.  相似文献   
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