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161.
We describe a case of hemothorax following central venous catheter (CVC) insertion in an infant. Presumably injury occurred as a result of perforation with the dilator. Strategies to reduce the risk of complications and possible factors influencing the unsatisfactory delay in diagnosis, including the role of 'Fixation Error', are discussed.  相似文献   
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Postembolic colonic infarction   总被引:12,自引:0,他引:12  
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BACKGROUND: Blunt carotid artery injury (BCI) remains a rare but potentially lethal condition. Recent studies recommend that aggressive screening based on broad criteria (hyperextension-hyperflexion mechanism of injury, basilar skull fracture, cervical spine injury, midface fracture, mandibular fracture, diffuse axonal brain injury, and neck seat-belt sign) increases the rate of diagnosis of BCI by 9-fold. If this recommendation becomes a standard of care, it will require a major consumption of resources and may give rise to liability claims. The benefits of aggressive screening are unclear because the natural history of asymptomatic BCI is unknown and the existing treatments are controversial. HYPOTHESIS: The lack of an aggressive angiographic screening protocol does not result in delayed BCI diagnosis or BCI-related neurologic deficits. METHODS: A 10-year medical record review of patients with BCI was undertaken in 2 level I academic trauma centers. In both centers, urgent screening for BCI was performed in patients with focal neurologic signs or neurologic symptoms unexplainable by results of computed tomography of the brain as well as in selected patients undergoing angiography for another reason. RESULTS: Of 35 212 blunt trauma admissions, 17 patients (0.05%) were diagnosed as having BCI. Six showed no evidence of BCI-related neurologic symptoms during hospitalization or prior to death as a result of associated injuries. Eleven sustained a BCI-related stroke, 9 of whom had it within 2 hours of injury. The remaining 2 had a delayed diagnosis (9 and 12 hours after injury) and received only anticoagulation because the lesions were surgically inaccessible. Just 1 of these 2 patients met the criteria for BCI screening and could have been offered earlier treatment, of uncertain benefit, if we had adopted an aggressive screening policy. CONCLUSIONS: Of the few patients with BCI, most remain asymptomatic or develop neurologic deficits shortly after injury. Although a widely applied, resource-consuming screening program may increase the rate of early diagnosis of BCI, an improvement in outcome is uncertain. A cost-effectiveness analysis should be done before trauma surgeons accept an aggressive screening protocol as the standard of care.  相似文献   
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BACKGROUND AND PURPOSE: Increasing use of CT for evaluating neurologic disease may expose patients to considerable levels of ionizing radiation. We compared the image quality of low-mAs head CT scans with that of conventional nonenhanced scans. METHODS: Conventional head CT scans were obtained in 20 patients (all >65 years with history of non-CNS malignancy) by using a multidetector technique: 170 mA and 1-second scanning time (ie, 170 mAs), 140 kVp, table speed of 7.5 mm per rotation, pitch of 0.75, section thickness of 5 mm, and field of view of 25 mm. A limited volume helical data acquisition covering four 5-mm-thick images was obtained by using 90 mAs but otherwise the same parameters. Three neuroradiologists visually rated the resulting images for quality in a blinded comparison. Representative 1- to 4-mm(2) regions of interest were chosen in gray matter and white matter locations. Conspicuity and the contrast-to-noise ratio were analyzed. Statistical comparisons were done by using the Student t test. RESULTS: Mean gray matter conspicuity was not significantly different between the 170- and 90-mAs groups (0.39 +/- 0.19 vs 0.41 +/- 0.03, P =.32). Mean gray matter contrast-to-noise ratio was approximately 22% higher with 170 mAs than with 90 mAs (1.77 +/- 0.52 vs 1.39 +/- 0.38, P =.005). All 90-mAs images were rated as having slightly greater image noise than the 170-mAs scans but with sufficient perceived resolution. CONCLUSION: Although 90-mAs head CT images were moderately noisier than 170-mAs images, they were rated as having acceptable diagnostic quality.  相似文献   
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BACKGROUND: Hypertension is one of the most frequently diagnosed chronic medical conditions in the United States and imposes a substantial financial and social burden on Americans. OBJECTIVE: The aim of this study was to compare the cost of health care resources for hypertensive patients taking analgesics stratified by having controlled versus uncontrolled hypertension. METHODS: This was a retrospective, database analysis of data for managed-care patients in Maryland and Washington, DC, recorded from February 1, 1999, to July 31, 2001. Hypertensive patients who were taking analgesics were stratified by their hypertension control status using a claims-based algorithm. Annualized costs and differences in annualized costs calculated for the periods before and after the initiation of analgesics were compared by patient hypertension control status. RESULTS: Of the 9805 patients in the study (mean [SD] age, 49.8 [12.04] years), 2523 (25.73%) were categorized as having uncontrolled hypertension. The mean total annualized costs differed significantly between the controlled and uncontrolled hypertension groups by 2568 dollars (P < 0.001). The annualized costs for emergency-department visits and hospitalizations for uncontrolled hypertensive patients exceeded those for controlled hypertensive patients by 9.3% and 28.0%, respectively. The differences between the postindex- and preindex-period costs for health care resources were 1972 dollars with controlled hypertension and 2961 dollars with uncontrolled hypertension (P < 0.001). The results of linear regression, after adjustments were made for preindex costs and other covariates, indicated that patients with uncontrolled hypertension had significantly increased billed annualized costs (P < 0.001). CONCLUSIONS: These data suggest that the costs of health care resources were significantly higher for analgesic users with uncontrolled hypertension than for analgesic users with controlled hypertension. A considerable proportion of the cost differential was directly attributable to hypertension-related treatment care.  相似文献   
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