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We report a case of successful transvenous, catheter-based, cavotricuspid isthmus ablation for treatment of atrial flutter using microwave energy. Microwave energy was delivered at 900–930 MHz using 21 W of power. Bidirectional cavotricuspid isthmus conduction block was achieved by microwave ablation without any patient discomfort or complication during the procedure. Our initial experience suggests that transcatheter microwave ablation is feasible for the cure of typical atrial flutter.  相似文献   
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BACKGROUND: Despite increasing numbers of morbidly obese patients admitted to acute care facilities for surgery or treatment of nonsurgical conditions, there is little evidence of the problems nurses face in providing care to these patients. Anecdotal evidence suggests that the care of these patients is more demanding than the care of nonobese patients. The objective of this study was to describe nurses' perceptions of the challenges that they face when caring for morbidly obese patients. METHODS: Focus groups of nurses from a tertiary care facility were convened. A trained facilitator posed questions to the group concerning various aspects of care for morbidly obese patients. Comments of respondents were categorized using NVIVO software. RESULTS: Nurses reported concerns about the increased staffing needs required for care of these patients and the particular challenges of the physical care. Concerns also included the availability, placement, and use of specialized equipment. Room size and the absence of some equipment were also problematic. Finally, nurses perceived safety issues, both for themselves and their patients. CONCLUSIONS: Morbidly obese patients in the acute care setting require specialized nursing care in terms of techniques, levels of staffing required, and the use of specialized equipment.  相似文献   
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BACKGROUND: The impact of infection with Burkholderia gladioli in cystic fibrosis, other chronic airway diseases and immunosuppressed patients is unknown. METHODS: A six-year retrospective review of all patients with B. gladioli infection was performed in a tertiary referral center with cystic fibrosis and lung transplantation programs. In addition, a targeted survey of all 251 lung transplant recipients was performed. Available B. gladioli isolates were analyzed via pulsed field gel electrophoresis. RESULTS: Thirty-five patients were culture positive for B. gladioli, including 33 CF patients. No bacteremia was identified. Isolates were available in 18 patients and all were genetically distinct. Two-thirds of these isolates were susceptible to usual anti-pseudomonal antibiotics. After acquisition, only 40% of CF patients were chronically infected (> or =2 positive cultures separated by at least 6 months). Chronic infection was associated with resistance to > or =2 antibiotic groups on initial culture and failure of eradication after antibiotic therapy. The impact of acquisition of B. gladioli infection in chronic infection was variable. Three CF patients with chronic infection underwent lung transplantation. One post-transplant patient developed a B. gladioli mediastinal abscess, which was treated successfully. CONCLUSIONS: The majority of patients' culture positive for B. gladioli at our center have CF. B. gladioli infection is often transient and is compatible with satisfactory post-lung transplantation outcomes.  相似文献   
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Edema develops when lymph does not return to the venous circulation at a rate equal to the rate of capillary filtration. Fetal sheep develop edema as well as an increased central venous pressure while undergoing atrial pacing at 320 beats per min. We hypothesized that the increased central venous pressure augmented the appearance of fetal edema by impairing the return of thoracic duct lymph to the venous circulation. To investigate this hypothesis, we studied the effect of outflow pressure upon thoracic duct lymph flow in 10 unanesthetized fetal sheep who had low resistance lymph catheters placed in the cervical thoracic duct near its junction with the left jugular vein. After the ewe and fetus recovered for 5 d, we altered the outflow pressure of the lymph catheter by adjusting its height with respect to amniotic fluid pressure and measured the resultant change in thoracic duct lymph flow rate. We found that lymph flow rate was constant over the range of outflow pressures (central venous pressures) normally encountered but decreased in a linear fashion at pressures greater than 0.68 kPa (5.1 torr). Lymph flow stopped at an outflow pressure of 2.40 kPa (18 torr). The data points are best fit by two lines obtained by a piecewise linear regression rather than a single line obtained from a linear regression. We conclude that fetal thoracic duct lymph flow is sensitive to elevations in outflow pressure. Lymph flow begins to diminish at outflow pressures corresponding to central venous pressures commonly encountered in pathologic conditions and may augment the appearance of fetal edema.  相似文献   
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