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1.
Die Anaesthesiologie - Auch wenn für Anästhesiologen über Jahrzehnte die Prophylaxe und Therapie postoperativer Schmerzen im Rahmen des postoperativen Patientenkomforts an vorderster...  相似文献   
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Objective

Low psoas muscle area is shown to be an indicator for worse postoperative outcome in patients undergoing vascular surgical. Additionally, it has been associated with longer durations of hospital stay in patients with cancer who undergo surgery and subsequently greater health care costs in Europe and the United States. We sought to evaluate this effect on hospital expenditure for patients undergoing vascular repair in a health care system with universal access.

Methods

Skeletal muscle mass was assessed on preoperative abdominal computed tomography scans of patients undergoing open aortic aneurysm repair in a retrospective fashion. The skeletal muscle index (SMI) was used to define low muscle mass. Health care costs were obtained for all patients and the relationship between a low SMI and higher costs was explored using linear regression and cross-sectional analysis.

Results

We included 156 patients (81.5% male) with a median age of 72 years undergoing elective surgery for infrarenal abdominal aortic aneurysm in this analysis. The median SMI for patients with low skeletal muscle mass was 53.21 cm2/kg and for patients without, 70.07 cm2/kg. Hospital duration of stay was 2 days longer in patients with low skeletal muscle mass as compared with patients with normal (14 days vs 11 days; P = .001), as was duration of intensive care stay (3 days vs 1 day; P = .01). The median overall hospital costs were €10,460 higher for patients with a low SMI as compared with patients with a normal physical constitution (€53,739 [interquartile range, €45,007-€62,471] vs €43,279 [interquartile range, €39,509-€47,049]; P = .001). After confounder adjustment, a low SMI was associated with a 14.68% cost increase in overall hospital costs, for a cost increase of €6521.

Conclusions

Low skeletal muscle mass is independently associated with higher hospital as well as intensive care costs in patients undergoing elective aortic aneurysm repair. Strategies to reduce this risk factor are warranted for these patients.  相似文献   
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OBJECTIVE: To analyse the image quality and diagnostic effectiveness of a new C-arm-based 3D imaging method (C-arm-CT) for intraoperative evaluation of screw osteosyntheses adjacent to a peripheral joint. MATERIALS AND METHODS: Insertion of screws into four cadaveric specimens simulated the surgical treatment of talus neck fractures. Ten orthopedic surgeons and 10 radiologists evaluated X-ray, C-arm fluoroscopy, C-arm-CT and CT images. RESULTS: The best image quality was obtained with X-rays (p < 0.001), followed by C-arm fluoroscopy (2D) and CT, with the C-arm-CT (3D) being rated lowest (p < 0.001). The most correct diagnoses were obtained with CT and C-arm-CT (with no statistical difference between them), while C-arm-fluoroscopy was inferior (p < 0.001) and X-rays were the worst (p < 0.05). CONCLUSIONS: Even if the image quality of C-arm-CT is definitely inferior to that of CT, screw misplacements can be reliably detected using C-arm-CT. As compared to the current standard procedures (intraoperative fluoroscopy and postoperative radiography), C-arm-CT performed better. C-arm-CT is ideally suited to the intraoperative diagnosis of high-contrast inquiries like bone fragments and OS material, especially at the extremities. Coupling of the new 3D imaging to existing navigation systems is possible. C-arm-CT will support the further development and implementation of open and minimally invasive surgical procedures.  相似文献   
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In contrast to conventional film angiography, the perfusion pattern of hepatic arterial chemotherapy was consistently visualized by DSA in 40 patients with implanted Infusaid pump or Port-A devices. Incomplete perfusion of a liver region by the cytotoxic agent was recognized by DSA as accurately as by nuclide scintigraphy. Furthermore, DSA appeared to be more sensitive in determining aberrantly perfused extrahepatic regions; this was especially true when there was a nonligated right hepatic artery. Specific details of vascular lesions and associated complicating events also could be satisfactorily analyzed by DSA only.  相似文献   
8.
The purpose of this investigation was to determine differences in tissue composition of symptomatic and asymptomatic disc herniations as reflected in T1 and T2 relaxation times (quantitative magnetic resonance investigation of the lumber spine. The longitudinal and transverse magnetic rlaxation times (T1 and T2, respectively) were calculated from a set of 20 images obtained with five single-slice/multi-echo sequences at different repetition time values on a commercial whole-body system (1.5 T). Twenty-two symptomatic and asymptomatic disc herniations could be matched according to age, gender, disc level, and the extent of herniation (protrusion or extrusion) and were compared with regard to T1 and T2 relaxation times. Symptomatic disc herniations exhibited significantly (pT1 < 0.04 and pT2 < 0.003) shorter T1(ΔT1:–182.1 milliseconds, ?15%) and T2(ΔT2: ?11.0 milliseconds, ?21%) relaxation times than matched asymptomatic herniations. Symptomatic disc herniations also exhibited more advanced disc degeneration as graded by Pearce's criteria (p < 0.01). These results suggest that symptomatic and morphologically matched asymptomatic disc herniations differ with regard to disc matrix composition.  相似文献   
9.
A new method for the selective spin labeling of left- or right-sided supplying arteries of the brain without the need for additional RF coils is demonstrated. A clinical 1.5 T scanner was used. The spatial selectivity of the labeling process is based on the limited coverage of the excitation field of a standard send/receive head coil together with an oblique positioning of the labeling plane. A computer simulation was used to optimize key labeling parameters under the condition of laminar flow. The validity of the computer model results was confirmed by MRI measurements with a flow model. For human studies, a double-inversion continuous arterial spin labeling (CASL) sequence was modified to allow for arbitrary positioning of the labeling plane. The obtained perfusion-weighted images showed a clear delineation of the perfusion territories of the selected arteries in the anterior circulation of the brain and good gray/white matter contrast.  相似文献   
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