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OBJECTIVE: To investigate the effect of preoperative initiation of low molecular weight heparin as prophylaxis for deep venous thrombosis in patients at risk of developing surgical-site infections after knee arthroplasty. DESIGN: Case-control study nested in a cohort. The incidence of surgical-site infection in the cohort was calculated. With the use of data extracted from medical histories and after adjustment for other risk factors, the effect of preoperative heparinization on the risk of incisional and prosthetic infection among case-patients and control-patients (1:3 ratio) was assessed. SETTING: Orthopedic department in a tertiary-care referral hospital. PATIENTS: A cohort of 160 consecutive patients who had received prosthetic knee implants between October 1, 2001, and November 30, 2003. RESULTS: Eighteen patients with surgical-site infections were identified, yielding an incidence of incisional and prosthetic infection of 6.9 (95% confidence interval [CI95], 3.5 to 12.0) and 4.4 (CI95, 1.8 to 8.8) cases per 100 patients undergoing surgery, respectively. Surgical-site infection was associated with preoperative use of low molecular weight heparin (odds ratio [OR], 6.2 after adjustment for medical and surgical factors; CI95 1.5 to 23). Prosthetic infection was strongly associated with preoperative use of prophylaxis (OR, undetermined [100% exposure in case-patients vs 35% exposure in control-patients]; P = .002), but incisional surgical-site infection was not. CONCLUSION: The use of low molecular weight heparins immediately before knee arthroplasty as prophylaxis for deep venous thrombosis should be questioned because of probable increased risk of prosthetic infection.  相似文献   
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Hanpeter DE  Demetriades D  Asensio JA  Berne TV  Velmahos G  Murray J 《The Journal of trauma》2000,49(4):689-94; discussion 694-5
BACKGROUND: The standard evaluation of mediastinal gunshot wounds usually requires angiography and either esophagoscopy or esophagography. In the present study, we have evaluated the role of helical computed tomographic (CT) scanning in reducing the need for angiographic and esophageal studies. METHODS: This was a prospective study of patients with mediastinal gunshot wounds who were hemodynamically stable and would otherwise require angiography and esophageal evaluation. All patients underwent CT scan of the chest with intravenous contrast to delineate the missile trajectory. If the missile tract was in close proximity to the aorta, great vessels, or esophagus, then traditional evaluation with angiographic or esophageal evaluation was pursued. RESULTS: A total of 24 patients met the inclusion criteria and underwent CT scan evaluation of their mediastinal gunshot wounds. One patient was taken for sternotomy to remove a missile embedded in the myocardium solely on the basis of the result of the CT scan. Because of proximity of the bullet tract, 12 patients required additional evaluation with eight angiograms and nine esophageal studies. One of these patients had a positive angiogram (bullet resting against the ascending aorta) and underwent sternotomy for missile removal; all other studies were negative. The remaining 11 patients were found to have well-defined missile tracts that approached neither the aorta nor the esophagus, and no additional evaluation was pursued. There were no missed mediastinal injuries in this group. Overall, 12 of 24 patients (50%) had a change in management (either received an operation or avoided additional radiographic or endoscopic evaluation) on the basis of the CT scan. CONCLUSION: The helical CT scan provides a rapid, readily available, noninvasive means to evaluate missile trajectories. This permits accurate assessment of potential mediastinal injury and reduces the need for routine angiographic and esophageal studies.  相似文献   
84.
Approach to the management of complex hepatic injuries   总被引:13,自引:0,他引:13  
BACKGROUND: Complex hepatic injuries American Association for the Surgery of Trauma Organ Injury Scale grades IV and V incur high mortality rate ranging from 40 to 80%, respectively. The objective of this study is to assess the clinical experience with an aggressive approach to the management of these, the most complex of hepatic injuries. METHODS: This is a retrospective 6-year study (1992-1997) at an American College of Surgeons urban Level I trauma center of patients sustaining complex hepatic injuries whose interventions included surgery, angiographic embolization, endoscopic retrograde cholangiopancreatography plus biliary stenting and percutaneous computed tomographic-guided drainage. The main outcome measure was survival. RESULTS: A total of 22 patients sustaining complex hepatic injuries; mean age of 26 years (range, 10-52 years), mean Revised Trauma Scale score of 9.9, mean Injury Severity Score of 32 (range, 16-75), American Association for the Surgery of Trauma - Organ Injury Scale grade IV (13 cases); grade V (9 cases). Mean estimated blood loss was 4,600 mL; mean number of units of blood transfused was 15. The patients underwent the following interventions: surgery (n = 22), re-operated (n = 13), mean number of operations 1.6 (range, 1-4), extensive hepatotomy and hepatorrhaphy (n = 17), nonanatomic resection (n = 7), formal hepatectomy (n = 4), packing (n = 10), direct approach to hepatic veins (n = 3); angiographic embolization (n = 15); endoscopic retrograde cholangiopancreatography and stenting (n = 5); computed tomographic guided drainage (n = 6). Mean length of stay in the intensive care unit was 21 days (range, 2-134 days), mean hospital length of stay was 40 days (range, 2-147 days). Overall mortality rate was 14% (3 of 22 cases), hepatic mortality rate was 9% (2 of 22 cases), mortality rate by injury grade was 8% grade IV (1 of 13 cases) and 22% grade V (2 of 9 cases). CONCLUSION: In this select patient population, improvements in mortality rates can be achieved with an aggressive approach to the management of complex hepatic injuries, including surgery, early packing, angiographic embolization, endoscopic retrograde cholangiopancreatography and stenting of biliary leaks, and drainage of hepatic abscesses.  相似文献   
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The aim of this paper was to review the clinical applications of four-dimensional ultrasonography in the assessment of fetal behavior. With the use of a computerized database, articles on three-dimensional ultrasonography were reviewed. Several applications of dynamic three-dimensional ultrasonography have been reported, including imaging of fetal movements, facial expression and fetal hand movements. The importance of the assessment of fetal behavior by four-dimensional sonography is stressed. Four-dimensional sonography seems to be a useful imaging tool for clinical problem solving in perinatology, especially in observing the development of the central nervous system in utero.  相似文献   
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Background The clinical characteristics of vitiligo in children and adolescents with an emphasis on thyroid dysfunction have only been reported in a few studies. Objective The purpose of this study was to examine the characteristics of children and adolescents with vitiligo and compare the incidence of thyroid dysfunction between them and controls without vitiligo at the same age. Methods A retrospective analysis of 324 Korean children and adolescents with vitiligo was performed. The results of thyroid function screening tests in them (n = 254) were compared with controls (n = 122). Results Of the total 324 children and adolescents with vitiligo, vitiligo vulgaris was the most common type (42.3%) and the most commonly involved site was the face (54.6%). A total of 15 of 254 (5.9%) patients screened for thyroid function were diagnosed with thyroid disease (four had Hashimoto’s thyroiditis; two, Graves’ disease; seven, subclinical hypothyroidism; and two, subclinical hyperthyroidism). None of the 50 patients with segmental vitiligo showed any thyroid dysfunction (P = 0.047). There was no significant difference in the incidence of thyroid disease between children and adolescents with vitiligo and the control group, in which seven of 122 (5.7%) showed thyroid dysfunction. Conclusion In this study, we demonstrated the characteristics of children and adolescents with vitiligo and also observed no significant difference in the incidence of thyroid disease between children and adolescents with vitiligo and the control group.  相似文献   
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