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141.
The objective of this prospective, randomized, double-blind study was to determine if preoperative administration of a femoral nerve block reduces the amount of morphine needed for postoperative analgesia after total knee arthroplasty (TKA). Forty-two patients undergoing TKA were randomly assigned to receive either a femoral nerve block (0.50% bupivacaine hydrochloride with epinephrine 1:200,000) or matching placebo. Results showed postoperative morphine use was significantly lower in patients who received the nerve block (25.5 vs 37.5 mg, P = .016); however, the 2 groups had similar pain scores and rehabilitative outcomes. In general, a preoperative femoral nerve block is a safe and effective adjunct for decreasing morphine use for post-TKA analgesia.  相似文献   
142.
BACKGROUND: A carbonated apatite cement (NORIAN SRS) was used as a bone mineral substitute for the calvaria or viscerocranium in 27 patients. It has the consistency of a paste and hardens at physiologic pH and body temperature due to dahllite crystallization, which has the stoichiometric formula Ca(8.8)(HPO(4))(0.7)(PO(4))(4.5)(CO(3))(0.7)(OH)(1.3). MATERIAL AND METHODS: The cement was used for posttraumatic bone defects in the orbital, periorbital or malar regions (nine patients), posttraumatic deformities of the frontal bone (six patients), tumour-dependent bony defects of the calvaria (two patients) and posttraumatic or cystic defects of the mandible (five patients). In another five patients, the material was used to augment the atrophic anterior mandible in combination with the insertion of dental implants. Follow-up varied between 6 and 40 months (mean: 29 months). RESULTS: There was no inflammatory reaction surrounding the implanted material. There was no sign of infection in any of the patients and only one case of partial wound dehiscence with superficially exposed material. The defect fillings and augmentations were successful in all patients. None of the 19 dental implants which were inserted in combination with the material showed any sign of infection or loosening. Also, there was no loosening of the implants after loading (mean follow-up: 15 months). From the check-up radiographs, the material could be seen as a dense, radio-opaque structure. There were no material fractures or dislocations. Radiologically, the material seemed to be completely replaced by bony tissue after 30 months. CONCLUSION: Our 5-year clinical experience suggests that the material is a suitable bone mineral substitute for cranio-maxillofacial surgery especially for moderate-sized defects of the calvaria and forehead bone. It has advantages over preformed, solid bone substitute materials, and, due to its initial plasticity and eventual great compressive strength, it can also stabilize dental endosseous implants in the atrophic mandible.  相似文献   
143.
OBJECTIVE: Reoperative cardiac surgery after previous coronary artery bypass grafting represents a surgical challenge due to the potential for injury to patent coronary grafts, aorta or right ventricle. Standard preoperative imaging using a coronary angiogram and chest radiograph (CXR) often results in inaccurate assessment of mediastinal anatomy. We aimed to evaluate 3D volume rendered computed tomographic imaging as an adjunct to standard preoperative assessment of patients requiring cardiac surgery in whom coronary artery revascularization had been performed in the past. METHODS: Between January 2003 and January 2004, 33 patients with previous coronary revascularization referred for reoperative cardiac surgery underwent preoperative 3D CT imaging in order to optimize the surgical approach. The mean age in this patient population was 72+/-8 years. The combined evaluation of CXR and conventional angiography offered incomplete insight into pertinent mediastinal topography in 85% of patients (28/33). RESULTS: The correlations for distances of the left internal mammary artery (LIMA) to left anterior descending artery (LAD) graft from the midline and posterior sternum obtained by CT angiography (CTA) and CXR were poor, R=0.56 and 0.49, respectively. The correlation coefficients for distances between the right ventricle and the aorta to the sternum obtained by the same methods were similarly marginal, 0.58 and 0.48, respectively. The correlation coefficients for distances between the LIMA to LAD, circumflex and right coronary artery grafts from the midline obtained by CTA and conventional angiography were 0.54, -0.13 and 0.43, respectively. In seven patients (21%) the surgical strategy was modified based on the location of patent grafts in the mediastinum. The hospital mortality was 17% (5/29). Intraoperative injuries to vital structures were encountered in two patients (7%). No injuries to patent LIMA or the aorta were encountered. CONCLUSIONS: The 3D CT imaging technique is useful in defining the optimal surgical strategy for reoperative cardiac surgery. We found that CTA is superior to CXR and conventional angiography in defining the position of patent grafts and vital structures in relation to the midline and posterior sternum. Preoperative mapping of patent coronary grafts and other vital mediastinal structures reduces the morbidity of the reoperation through modification of surgical approaches.  相似文献   
144.
Fluoroscopy is the most common tool for the intraoperative control of long-bone fracture reduction. Limitations of this technology include high radiation exposure for the patient and the surgical team, limited visual field, distorted images, and cumbersome verification of image updating. Fluoroscopy-based navigation systems partially address these limitations by allowing fluoroscopic images to be used for real-time surgical localization and instrument tracking. Existing fluoroscopy-based navigation systems are still limited as far as the virtual representation of true surgical reality is concerned. This article, for the first time, presents a reality-enhanced virtual fluoroscopy with radiation-free updates of in situ surgical fluoroscopic images to control metaphyseal fracture reduction. A virtual fluoroscopy is created using the projection properties of the fluoroscope; it allows the display of detailed three-dimensional (3D) geometric models of surgical tools and implants superimposed on the X-ray images. Starting from multiple registered fluoroscopy images, a virtual 3D cylinder model for each principal bone fragment is constructed. This spatial cylinder model not only supplies a 3D image of the fracture, but also allows effective fragment projection recovery from the fluoroscopic images and enables radiation-free updates of in situ surgical fluoroscopic images by non-linear interpolation and warping algorithms. Initial clinical experience was gained during four tibia fracture fixations that were treated by LISS (Less Invasive Stabilization System) osteosynthesis. In the cases operated on, after primary image acquisition, the image intensifier was replaced by the virtual reality system. In all cases, the procedure including fracture reduction and LISS osteosynthesis was performed entirely in virtual reality. A significant disadvantage was the unfamiliar operation of this prototype software and the need for an additional operator for the navigation system.  相似文献   
145.
Zusammenfassung Suizide gehören im Jugendalter zu den häufigsten Todesursachen. Die Herstellung eines Gesprächskontakts mit dem suizidalem Kind oder Jugendlichen und den Eltern in einer neutralen akzeptierenden Haltung ist dabei von zentraler Bedeutung. Die Aufgabe des Notfallarztes vor Ort besteht darin, die vitale Gefährdung einzuschätzen. In der Notaufnahme eines Krankenhauses sind die Entstehungsbedingungen der suizidalen Handlung, das Vorliegen weiterer Verhaltensprobleme, aufrechterhaltende Bedingungen im familiären Umfeld zu klären und eine weiterführende Krisenintervention einzuleiten. Die Aufnahme in einer Klinik, in der kinderpsychiatrische Fachkompetenz verfügbar ist, ermöglicht eine detaillierte Bestandsaufnahme und Aufarbeitung. In den daran anschließenden Behandlungsschritten sollen geeignete Problemlösemöglichkeiten und eine Zukunftsorientierung entwickelt werden.  相似文献   
146.
Dear Professor Lian-Sheng Ma, Professor Michael Hobsley and I have greatly enjoyed reading the account of all you have done towards the development of "The World Journal of Gastroenterology", as described in the article by Zhen-Xi Li in the November 21st. Issue of the Journal.  相似文献   
147.
148.
OBJECTIVE: The purpose of this prospective study was to determine the positive predictive value (PPV) of the point of maximal posterior joint line tenderness (JLT), as a clinical sign, to diagnose underlying meniscal tears. METHODS: We conducted a prospective study of patients requiring arthroscopic surgery, who consecutively presented to the University of Calgary's Sport Medicine Centre. The femurotibial joint line was palpated for the point of maximal tenderness. We recorded the data on the arthroscopy report. A second examiner (orthopedic sport medicine surgical fellow or sport medicine physician) performed the same protocol. An arthroscopist documented the site of pathology as detected by arthroscopy. RESULTS: We found a PPV of 60.0% and a negative predictive value of 62.5%, suggesting that maximal posterior JLT may be predictive of meniscal pathology. The sensitivity and specificity were 84.6% and 31.2%, respectively (p = 0.155), with Fisher's exact test. The kappa score assessed interobserver reliability and was good at 0.48. Patients with maximal posterior JLT but no meniscal pathology did have other confounding pathology and patients with no maximal posterior JLT who had meniscal pathology usually had confounding knee pathology. CONCLUSIONS: We found a PPV of 60.0% of maximal posterior JLT and meniscal pathology located at the same anatomical site on arthroscopic examination.  相似文献   
149.
The prevalence of adult smoking in the United States declined from 42.4% in 1965 to 20.9% in 2005. Much of the success in reducing the prevalence of adult smoking over the past four decades can be attributed to tobacco control policies. This paper provides an overview of public health initiatives for smoking cessation in the United States and provides a review of the existing literature on the effects of these tobacco control initiatives on adult smoking cessation.  相似文献   
150.
Background The clinical course in acute necrotizing pancreatitis is mainly determined by bacterial infection of pancreatic and peripancreatic necrosis. The effect of two antibiotic regimens for early and late treatment was investigated in the taurocholate model of necrotizing pancreatitis in the rat. Materials and methods Seventy male Wistar rats were divided into five pancreatitis groups (12 animals each) and a sham-operated group (10 animals). Pancreatitis was induced by intraductal infusion of 3% taurocholate under sterile conditions. Animals received two different antibiotic regimes (20 mg/kg imipenem or 20 mg/kg ciprofloxacin plus 20 mg/kg metronidazole) early at 2, 12, 20, and 28 h after induction of pancreatitis or late at 16 and 24 h after induction of pancreatitis or no antibiotics (control). Animals were examined after 30 h for pancreatic and extrapancreatic infection. Results Early and late antibiotic treatment with both regimes could significantly reduce pancreatic infection from 58 to 8–25%. However, extrapancreatic infection was only reduced by early antibiotic therapy. While quinolones also reduced bacterial counts in small and large bowel, imipenem did not. Conclusions In our animal model of necrotizing pancreatitis, early and late treatment with ciprofloxacin/metronidazole and imipenem reduce bacterial infection of the pancreas. Extrapancreatic infection, however, is reduced significantly only by early antibiotic treatment. The effectivity of early antibiotic treatment in the clinical setting should be subject to further investigation with improved study design and sufficient patient numbers.  相似文献   
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