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101.
OBJECTIVES: To compare longitudinal changes in healthcare costs between fallers admitted to the hospital at the time of the fall (admitted), those not admitted to the hospital (nonadmitted), and nonfaller controls; test hypotheses related to differences in mean costs between and within these groups over time; and estimate the costs attributable to falling. DESIGN: Longitudinal cohort. SETTING: Group Health Cooperative of Puget Sound. PARTICIPANTS: Seven thousand nine hundred ninety‐three nonadmitted fallers, 976 admitted fallers, and 8,956 nonfallers aged 67 and older enrolled in an integrated healthcare delivery system. Fallers were identified according to fall‐related E‐Codes and International Classification of Diseases, Ninth Revision codes recorded between January 1, 2004, and December 31, 2006. Nonfallers were frequency matched on age group and sex. MEASUREMENTS: Quarterly costs during a 3‐year period were modeled using generalized estimating equations. Covariates included index age, sex, RxRisk (a comorbidity adjuster), fall status, time, and interactions between fall status and time. RESULTS: Cost differences between the faller cohorts and nonfallers were greatest in quarters closest to the fall (all P<.01) and persisted throughout the entire year of follow‐up. Although nonfaller costs increased with time, faller cohort costs increased more quickly (all P<.01). For admitted fallers, 92% of costs incurred in the quarter of the fall were estimated to be attributable to falling ($27,745 of $30,038, P<.001). CONCLUSION: Falls for which medical attention are sought resulted in higher costs than for nonfallers for up to 12 months after a fall, particularly for falls requiring hospitalization. Prevention efforts should focus on reducing fall‐related injuries requiring hospitalization because they produce the highest excess costs and have a higher likelihood of 1‐year mortality.  相似文献   
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Using animal models or healthy volunteers, injection of lipopolysaccharide (LPS) or bacteria causes activation of macrophages with excessive synthesis and secretion of proinflammatory cytokines. Although these models mimic the effects of LPS in the host, they may represent more of an experimental expression of endotoxemia than natural infection itself. Therefore, as an ex vivo model of sepsis, whole blood from 15 patients with severe sepsis and 20 control patients without infection was stimulated with LPS to study the kinetics of mRNA expression and release of proinflammatory cytokines, tumor necrosis factor (TNF)-alpha, interleukin (IL)-1 beta, and IL-6. Stimulation of whole blood with 1 microgram/mL LPS resulted in a maximum increase of cytokine secretion in the control group, while a marked (P < .01) depression of TNF-alpha, IL-1 beta, and IL-6 release was observed in the septic group, which persisted up to 10 days after study enrollment. While IL-1 beta mRNA expression was similar in peripheral blood mononuclear cells (PBMCs) harvested from LPS-stimulated whole blood in septic and control patients, the half-life and consequently the expression of TNF-alpha and IL-6 mRNA were strongly reduced in the septic group. These data indicate a downregulatory mechanism of cytokine release in whole blood from patients with severe sepsis that occurs on different levels. Although excessive secretion of proinflammatory cytokines has been considered deleterious for the host, the reduced capacity of PBMCs in whole blood from septic patients to synthesize and secrete proinflammatory cytokines to an inflammatory stimulus may result in immunodeficiency, because these cytokines in low concentrations are involved in the upregulation of essential cellular and humoral immune functions.  相似文献   
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A number of studies have compared results after aortic procedures in diabetics vs nondiabetics but few have focused specifically on abdominal aortic aneurysm surgery. An analysis of prospective data was carried out in the Vascular Surgery Registry (Beth Israel Deaconess Medical Center, Boston, MA) and identified 421 patients (422 grafts) who underwent elective open repair of an abdominal aortic aneurysm between 1990 and 1999. The influence of diabetes mellitus on outcome was assessed by dividing the patients into two groups: 52 diabetic and 370 nondiabetic patients. Postoperative mortality was 1.7% overall (n = 7) and proportionally higher in the diabetic population, although this did not reach statistical significance (3.8% vs 1.4%, p = 0.19). However, cumulative survival at 1 year and 3 years was essentially identical for diabetic vs nondiabetic patients (91.0% vs 92.6% and 70.0% vs 73.5%, respectively) and did not diverge until 5 years after surgery (25.0% vs 50.9% respectively [p > 0.05]). Overall, major complications occurred in 11 diabetics (21.2%) vs 58 nondiabetics (15.7%, p = 0.32). Specific complications that were increased in the diabetic population included pancreatitis (5.8% vs 1.1%, p = 0.01) and pneumonia (11.5% vs 3.2%, p = 0.006). Notably, overall cardiac morbidity was not higher in patients with diabetes mellitus (1.9% vs 4.3%, p = 0.41). Our data suggest that after elective open abdominal aortic aneurysm repair, patients with diabetes mellitus may have a higher rate of certain complications when compared to patients without diabetes mellitus. These differences however, do not preclude the expectation of excellent results of open abdominal aortic aneurysm repair in patients with diabetes mellitus.  相似文献   
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Although sestamibi scanning has been shown to have greater sensitivity and specificity than other preoperative localization techniques for parathyroid adenoma, it is unclear whether preoperative scanning improves outcomes for parathyroid surgery. Data from 528 consecutive patients who underwent neck exploration for primary hyperparathyroidism by one surgeon were collected prospectively over a 5-yr period. Patients were classified by preoperative scanning status (no scan, positive scan, and negative scan), and outcomes were compared in terms of operative time, length of hospital stay, and cure rate. Patients who had undergone a previous parathyroid operation and patients who received alternate preoperative localization techniques (ultrasound, magnetic resonance imaging, and computed tomography) were excluded from the study. All scans were ordered by the referring physician-the surgeon made no recommendations for preoperative scanning. All groups were similar in terms of gender, age, anesthesia class, body habitus, and complication rate. There was no significant difference in cure rate between patients who had preoperative scanning (97.5%) vs. those who did not (99.3%); however, there was a significant difference in cure rate between the negative-scan group (92.7%) and the positive and no-scan groups (99.3%, P < 0.01). In patients without concomitant thyroid surgery, there was no significant difference in operative time between the no scan (42.4 +/- 14.9 min) vs. the all-scan group (40.2 +/- 15.2 min); however, there was a significant difference between the negative scan group (44.5 +/- 21.9 min) and the positive scan group (38.5 +/- 12.6 min, P < 0.01). There was no significant difference in length of hospital stay among the three groups. These results suggest that, although preoperative sestamibi scanning does not alter the outcome of parathyroid surgery, it does identify those patients who are less likely to be cured.  相似文献   
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Background Critical appraisal of safety, feasibility, and economic impact of thyroidectomy procedures using local (LA) or general anesthesia (GA) is performed. Methods Consecutive patients undergoing thyroidectomy procedures were selected from a prospective database from January 1996 to June 2003 of a single-surgeon practice at a tertiary center. Statistical analyses determined differences in patient characteristics, outcomes, operative data, and length of stay (LOS) between groups. A cohort of consecutive patients treated in 2002–2003 by all endocrine surgeons at the institution was selected for cost analysis. Results A total of 1,194 patients underwent thyroidectomy, the majority using LA (n = 939) and outpatient surgery (65%). Female gender (76%), body mass index ≥30 kg/m2 (29%), median age (49 years), and cancer diagnosis (45%) were similar between groups. Extent of thyroidectomy (59% total) and concomitant parathyroidectomy (13%) were similarly performed. GA was more commonly utilized for patients with comorbidity [15% vs. 10%, Anesthesia Society of America (ASA) ≥3; P < 0.001], symptomatic goiter (13% vs. 7%; P = 0.004), reoperative cases (10% vs. 6%; P = 0.01), and concomitant lymphadenectomy procedures (15% vs. 3%; P < 0.001). GA was associated with significant increase in LOS ≥24 hours (17 % vs. 4%) or overnight observation (49 % vs. 14%), P < 0.001. Operative room utilization was significantly associated with type of anesthesia (180 min vs. 120 min, GA vs. LA, P < .001) and impacted to a lesser degree by surgeon operative time (89 minutes vs. 76 minutes, GA vs. LA; P = .089). Overall morbidity rates were similar between groups (GA 5.8 % vs. LA 3.2%). The actual total cost (ATC) per case for GA was 48% higher than for LA and 30% higher than the ATC for all procedures (P = 0.006), with the combined weighted average impacted by more LA cases (n = 217 vs. 85). Conclusion These data from a large, unselected group of thyroidectomy patients suggest LA results in similar outcomes and morbidity rates to GA. It is likely that associated LA costs are lower.  相似文献   
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Receptors for prostaglandin E2 or histamine were measured on subpopulations of human lymphocytes, using the cyclic AMP increase after exposure to prostaglandin or histamine as an indicator for the presence of receptors. The cyclic AMP response to prostaglandin E2 was similar in unfractionated lymphocytes and the T-enriched and T-depleted fractions. Within the T-enriched population, T cells bearing a receptor for the Fc portion of IgG (T gamma-cells) had a 27.4-fold rise in cyclic AMP after exposure to prostaglandin E2, whereas the remaining T cells (non-T gamma cells) had a fourfold increase. It would appear that prostaglandin receptors are concentrated on a small subfraction of T gamma cells, comprising approximately 15% of the T-cell population. The cyclic AMP response to histamine was less than twofold in all lymphocyte fractions.  相似文献   
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