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51.
Susan Nixon died in 1881 following a surgical error. Her surgeon, Dr W. E. Warren, excised a normal 7-month gravid uterus under the misapprehension that he was removing a tubular pregnancy. It is believed that Mrs Nixon was the first woman in Australia to have an abdominal hysterectomy and the second to have a live Caesarean section. The surgical misadventure that resulted in Mrs Nixon's death became a public scandal, which gained currency through both parliamentary debate and the popular press. The purpose of referring to this case is to explore the mechanisms of accountability that surgeons faced in the 1880s--a decade of rapid change in the practice of surgery. The response of late nineteenth century society to surgical error and the resultant reaction of the medical profession have resonances that are relevant to surgeons practising today.  相似文献   
52.
Both benign and malignant breast lesions may exhibit intense contrast enhancement when imaged using gadolinium-enhanced MRI. We propose a quantitative approach for fitting dynamic signal intensity (SI) data that may distinguish benign from malignant lesions. We studied 78 lesions in 75 women (18 malignancies, 16 fibroadenomas, and 44 other benign breast lesions) to determine the potential of this model for decreasing false-positive MR results. Twenty-eight lesions showed no enhancement; all were benign. One lesion showed a complex pattern not amenable to region-of-interest analysis and was considered a false positive. SI versus time data for the remaining 49 lesions were fit to the proposed model. We found that one parameter, M, the normalized slope of the SI enhancement profile evaluated at half the maximal signal intensity, seemed to be highly correlated with malignancy and offered improved discrimination between malignant and benign lesions compared to a previously published two-point slope method.  相似文献   
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Pudendal nerve palsy is a reported complication of hip arthroscopy. We report a technique using a deflated taped beanbag rather than a perineal post. The patient is placed in the supine or lateral position on a fracture table. The beanbag is contoured around the patient’s flank and thorax. The distal aspect of the beanbag is placed no further than the iliac crest, and care is taken to avoid compression of the posterior aspect of the axillary region or the posterior humerus. The molded beanbag is deflated, a blanket is positioned over the abdomen and lower thorax, and with the use of 3-in-wide cloth tape, the patient and beanbag are secured to the operative table circumferentially. The superior margin of the deflated beanbag remains firm, preventing compression of the thorax and avoiding compromised ventilation. The arm on the operative side is placed across the chest and secured to avoid obstruction of the operative field. This patient positioning provides sufficient stability for adequate traction and good visualization while minimizing the risk of a pudendal nerve palsy.  相似文献   
57.
This study was designed to elucidate the cellular basis of risk of or protection from nephropathy in patients with type 1 diabetes. Entry criteria included diabetes duration of > or =8 years (mean duration, 22.5 years) and glomerular filtration rate (GFR) >30 ml x min(-1) x 1.73 m(-2). Patients were classified, on the basis of the estimated rate of mesangial expansion, as "fast-track" (upper quintile) or "slow-track" (lower quintile). A total of 88 patients were normoalbuminuric, 17 were microalbuminuric, and 19 were proteinuric. All three groups had increased glomerular basement membrane (GBM) width and mesangial fractional volume [Vv(Mes/glom)], with increasing severity from normoalbuminuria to microalbuminuria to proteinuria but with considerable overlap among groups. Vv(Mes/glom) (r = 0.75, P < 0.001) and GBM width (r = 0.63, P < 0.001) correlated with albumin excretion rate (AER), whereas surface density of peripheral GBM per glomerulus [Sv(PGBM/glom)] (r = 0.50, P < 0.001) and Vv(Mes/glom) (r = -0.48, P < 0.001) correlated with GFR. Vv(Mes/glom) and GBM width together explained 59% of AER variability. GFR was predicted by Sv(PGBM/glom), AER, and sex. Fast-track patients had worse glycemic control, higher AER, lower GFR, more hypertension and retinopathy, and, as expected, worse glomerular lesions than slow-track patients. Thus, there are strong relationships between glomerular structure and renal function across the spectrum of AER, but there is considerable structural overlap among AER categories. Given that normoalbuminuric patients may have advanced glomerulopathy, the selection of slow-track patients based on glomerular structure may better identify protected patients than AER alone.  相似文献   
58.
OBJECTIVES: Diagnostic accuracy of the ThinPrep process (Cytyc, Boxborough, MA) was compared with that of conventional (smear) cytopreparation for fine-needle aspiration (FNA) of head and neck masses. METHODS: In a prospective, randomized, single-blinded study, 209 patients served as their own controls and underwent 236 FNAs using ThinPrep and conventional (smear) cytopreparatory techniques. RESULTS: ThinPrep produced less air-drying artifact and less mechanical distortion than the conventional method. The conventional technique was diagnostic in 63% of samples; the ThinPrep technique was diagnostic in 55% of samples. When all results were combined, pathologists subjectively preferred the conventional technique but accepted use of ThinPrep as the only cytopreparatory technique for most head and neck masses. CONCLUSIONS: For adequately experienced cytopathologists, ThinPrep is acceptable for FNA of salivary masses, neck cysts, metastatic lymph nodes, and thyroid lesions. Conventional smear technique should be used for FNA of nonmetastatic lymphoid lesions. Use of ThinPrep can complement use of the conventional (smear) cytopreparatory technique when aspirate is nondiagnostic or bloody, when the patient has a blood-borne infectious disease, when the clinician is inexperienced, or when aspirate has entered the syringe.  相似文献   
59.
Mortality rates in geriatric patients with spinal cord injuries   总被引:1,自引:0,他引:1  
OBJECT: The authors undertook this study to evaluate the incidence of spinal cord injury (SCI) in geriatric patients (> or = 70 years of age) and examine the impact of patient age, extent of neurological injury, and spinal level of injury on the mortality rate associated with traumatic SCI. METHODS: A prospectively maintained SCI database (3481 patients) at a single institution was retrospectively studied for the period from 1978 through 2005. Parameters analyzed included patient age, admission American Spinal Injury Association (ASIA) motor score, level of SCI, mechanism of injury, and mortality data. The data pertaining to the 412 patients 70 years of age and older were compared with those pertaining to the younger cohort using a chi-square analysis. RESULTS: Since 1980, the number of SCI-related hospital admissions per year have increased fivefold in geriatric patients and the percentage of geriatric patients within the SCI population has increased from 4.2 to 15.4%. In comparison with younger patients, geriatric patients were found to be less likely to have severe neurological deficits (greater percentage of ASIA Grades C and D injuries), but the mortality rates were higher in the older age group both for the period of hospitalization (27.7% compared with 3.2%, p < 0.001) and during 1-year follow-up. The mortality rates in this older population directly correlate with the severity of neurological injury (1-year mortality rate, ASIA Grade A 66%, Grade D 23%, p < 0.001). The mortality rate in elderly patients with SCI has not changed significantly over the last two decades, and the 1-year mortality rate was greater than 40% in all periods analyzed. CONCLUSIONS: Spinal cord injuries in older patients are becoming more prevalent. The mortality rate in this patient group is much greater than in younger patients and should be taken into account when aggressive interventions are considered and in counseling families regarding prognosis.  相似文献   
60.
Background In the era of Helicobacter pylori treatment, the role of vagotomy in bleeding duodenal ulcers is debatable. National outcomes were evaluated to determine the current surgical treatment and use of vagotomy for bleeding duodenal ulcers. Methods Data from the Nationwide Inpatient Sample (NIS) were used from years 1999 to 2003. Patients were selected using diagnostic codes for acute duodenal ulcer bleed and procedure codes for simple oversew of a bleeding ulcer and vagotomy. Data were analyzed using multiple linear and logistic regression. Results Between 1999 and 2003, 100,931 patients with an acute bleeding duodenal ulcer were identified. Over time, there was a decrease in the number of acute bleeding ulcers (p = 0.027) and a decrease in the number of vagotomies (p = 0.027). A high co-morbidity index [odds ratio (OR), 0.60, p = 0.017], operation in the Midwest (OR 0.50, p < 0.001) and operation in the West (OR 0.68, p = 0.034) were predictive of no vagotomy during surgery for a bleeding duodenal ulcer. Conclusions A vagotomy is not commonly performed during surgical treatment of an acute bleeding duodenal ulcer. This variation in practice was not fully explained by patient characteristics. We must seek new evidence to determine the safety of combined medical and surgical management of this clinical problem. Presented at DDW/SSAT May 20–24, Los Angeles, California.  相似文献   
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