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61.
PURPOSE: In France, legislation mandates that the clinical diagnosis of brain death be confirmed by one paraclinical test before organ donation is allowed. That test may be either the electroencephalogram (EEG) or cerebral angiography. We report a case in which the clinical diagnosis of brain death was first confirmed by two EEGs performed according to the French guidelines, but ruled out by cerebral angiography. Considering that the EEG is no longer recommended to establish the diagnosis of brain death, we discuss the relevance of maintaining the EEG for brain death diagnosis in France. CLINICAL FINDINGS: A 58 yr-old man was admitted to the intensive care unit because of coma secondary to a massive subarachnoid hemorrhage with herniation below the falx shown by computed tomography. Clinical criteria of brain death were rapidly present. Two EEGs first confirmed the diagnosis but a four-vessel cerebral angiography was finally performed because the patient moved spontaneously. This cerebral angiography showed flow in the right internal carotid artery. A computed tomography performed the next day definitely confirmed the absence of brain death and organ donation did not occur. CONCLUSIONS: This case demonstrates the limitations of the EEG for this indication and suggests that angiography should be preferred. French legislation is probably maladjusted and would benefit by incorporating guidelines of other countries like Canada. International harmonization of criteria for brain death diagnosis would also be welcome.  相似文献   
62.
Pericardial puncture is the percutaneous insertion of a needle into the pericardial space to drain a pathological pericardial effusion. The challenge for the operating surgeon is to reach percutaneously a target zone in the vicinity of the mobile heart, in a soft-tissue environment. The surgeon's ability to accomplish this depends on his own mental picture of the effusion. CASPER is a navigation software using an optical localizer which assists the surgeon by enhancing the representation of the effusion and guiding the needle's progress. Using a localized and calibrated echographic probe, the surgeon acquires a set of images in the region of interest. This zone is then manually segmented on each image, a common zone is computed, and the surgeon defines a trajectory for the needle. During the puncture procedure, the surgeon follows the position of the localized needle on a computer monitor. After initial validation on an experimental phantom, a feasibility study was performed using canine and porcine models. The optical localization device was changed from an Optotrak to a Polaris device for easier use in the clinical setting. Prior to clinical application, various tests were performed concerning the mobility of the thoracic cage, the reproducibility of the thoracic position over several apneas, and the stability of anatomic structures relative to the thoracic cage. Finally, a first clinical application was successfully performed using this system. The present paper reports on these last two stages.  相似文献   
63.
OBJECTIVE: To assess the therapeutic effect of the extent of lymph node dissection performed in patients with a stage pI non-small-cell lung cancer (NSCLC). METHODS: We analysed data on 465 patients with stage I NSCLC who were treated with surgical resection and some form of lymph node sampling. The median number of lymph node sampled was 10 and the median number of ipsilateral mediastinal lymph node stations sampled was two. We chose to define a procedure that harvested 10 or more lymph nodes and sampled two or more ipsilateral mediastinal stations as a lymphadenectomy, by contrast with sampling when one or both criteria were not satisfied. The effect of the surgical techniques: lymph node sampling (LS; n=207) vs. lymphadenectomy (LA; n=258) on 30-day mortality and overall survival were investigated. RESULTS: A total of 6244 lymph nodes was examined, including 4306 mediastinal lymph nodes. The mean (+/-SD) numbers of removed lymph nodes were 7+/-6.1 per patient following LS vs.18.6+/-9.3 following LA (P=0.001). An average mean of 1+/-0.90 mediastinal lymph node station per patient was sampled following LS vs. 2.7+/-0.8 following LA (P<10(-6)). Overall 30-day mortality rates were 2.4 and 3.1%, respectively. LA was disclosed as a favourable prognosticator at multivariate analysis (Hazard Risk: 1.43; 95% Confidence Interval: 1.00-2.04; P=0.048), together with younger patient age, absence of blood vessels invasion, and smaller tumour size. CONCLUSIONS: Importance of lymph node dissection affects patients outcome, while it does not enhance the operative mortality. A minimum of 10 lymph nodes assessed, and two mediastinal stations sampled are suggested as possible pragmatic markers of the quality of lymphadenectomy.  相似文献   
64.
This study was undertaken to evaluate changes in relative (99m)Tc-hydrazinonicotinamide (HYNIC)-annexin V tumor uptake over time in patients undergoing chemotherapeutic treatment at baseline and at 5-7 h and 40-44 h after treatment initiation. Imaging results are related to clinical outcomes, as assessed with response evaluation criteria in solid tumors (RECIST). METHODS: We prospectively included 20 patients (11 men and 9 women; mean age, 59.8 y; range, 22-75 y) scheduled for chemotherapy (n = 19) or bisphosphonate treatment (n = 1). Curable disease was present in 5 patients. The other patients had metastatic disease and were treated in a palliative setting. Three of the 20 enrolled patients were excluded from analysis: 1 patient ultimately refused the proposed chemotherapy treatment; because of difficulties with the labeling procedure, 1 patient did not receive a pretreatment scan; and 1 patient presented with an allergic reaction (rash and nausea) to the (99m)Tc-HYNIC-annexin V formulation. The remaining 17 patients underwent 3 scintigraphic scans with (99m)Tc-HYNIC-annexin V: before treatment and 5-7 h and 40-44 h after treatment initiation. The tumor response was evaluated with RECIST and related to observed changes in the ratios of tumor activity to background activity for the largest known lesion; values exceeding 25% the baseline value on either the 5- to 7-h scan or the 40- to 44-h scan were considered significant. RESULTS: With the proposed sequential imaging protocol and a 25% change threshold, responders to treatment could be separated from nonresponders with a 94% accuracy (16/17 patients). CONCLUSION: Sequential (99m)Tc-HYNIC-annexin V imaging may allow for assessment of the response to chemotherapy within 3 d after treatment initiation.  相似文献   
65.
66.
OBJECTIVE: Dilation of aortic annulus, sinuses of Valsalva, and sinotubular junction (STJ) diameters are the characteristic lesions of aortic root aneurysm. The remodeling technique reduces STJ diameter and creates three neosinuses of Valsalva. Alternatively, the reimplantation technique reduces both annulus and STJ diameters to the detriment of aortic root dynamics. Although the remodeling technique is recognized as the most physiological valve-sparing procedure, aortic annulus dilation may jeopardize its results. A standardized approach that combines an external subvalvular aortic prosthetic ring annuloplasty with the remodeling technique is suggested. METHODS: Eighty-three patients underwent an elective aortic root remodeling procedure, either isolated (group 1, n=34) or combined with an external subvalvular aortic prosthetic ring annuloplasty (group 2, n=49). Preoperative aortic regurgitation was 1.59+/-1.1 (group 1) and 1.97+/-1.3 (group 2) (NS). The aortic annulus was more dilated in group 2 than in group 1 (27+/-2.77 mm vs 26.4+/-2.3 mm, p<0.01). Residual aortic regurgitation > or =grade II was the conversion criteria for aortic valve replacement. RESULTS: Operative mortality was 3.6% (n=3). Intraoperative conversion for valve replacement was 32.7% in group 1 (n=11) versus 4.2% in group 2 (n=2) (p<0.001). In group 1, preoperative annulus diameter was larger for converted than for valve-spared patients (27.6+/-1.7 mm vs 25.2+/-1.5 mm, p<0.02). In group 2, implanted aortic ring significantly reduced annulus diameter (20.6+/-1.8 mm) without significant aortic valve gradient (8.3+/-3 mmHg). Follow-up was 17.2+/-13.4 months (group 1) and 10.41+/-7.95 months (group 2). Reoperation for recurrent aortic regurgitation was 13% in group 1 (n=3) versus 4.2% in group 2 (n=2). Echocardiographic follow-up found residual aortic regurgitation < or =grade I in 17 patients in group 1 (90%) versus 43 patients in group 2 (95.5%) and of grade II in two patients in group 1 (10%) and two patients in group 2 (4.5%). CONCLUSION: The addition of external aortic prosthetic ring annuloplasty improves the remodeling technique's operative reproducibility and short-term results. Therefore, its use as a systematical adjunct to the remodeling procedure is suggested. However, further long-term evaluation comparing this valve-sparing procedure to composite graft replacement should define the best surgical strategy for aortic root aneurysm.  相似文献   
67.
OBJECTIVE: To determine whether bacterial cultures of the wounds of patients undergoing clean orthopedic surgery would help predict infection. METHODS: During 1 year, 1,256 cultures were performed for 1,102 patients who underwent clean orthopedic surgery. Results were analyzed to evaluate their ability to predict postoperative infection. RESULTS: The sensitivity, specificity, positive predictive value, and negative predictive value of the cultures were 38%, 92%, 7%, and 99%, respectively. CONCLUSIONS: Cultures performed during clean orthopedic surgery were not useful for predicting postoperative infection.  相似文献   
68.
To determine the prevalence of excessive daytime sleepiness (EDS) and that of dozing and sudden onset of sleep episodes (SOS) while driving in ambulatory patients with Parkinson's disease (PD) in France, a national sample of private and public neurologists was asked to recruit the first 10 consecutive nondemented PD patients. Each patient completed a questionnaire including the Epworth Sleepiness Scale (ESS) and the likelihood of dozing off and experiencing SOS episodes behind the wheel. Clinical and demographic data were collected. One thousand six hundred and twenty‐five patients with PD were included in the survey. Twenty‐nine percent of the patients suffered from EDS (ESS score ≥10) but only 0.8% declared a high chance of dozing while driving and 0.5% reported totally unpredictable SOS episodes while driving. Risk factors for EDS were male gender, reduced activity of daily living, and a high daily levodopa equivalent dosage. Risk factors for SOS episodes while driving were an ESS score ≥10, male gender, and low Hoehn and Yahr staging. EDS is common in ambulatory patients with PD and is a major risk factor for dozing and for SOS episodes behind the wheel in patients who drive. © 2007 Movement Disorder Society  相似文献   
69.
A significant reduction of kallikrein activity in urine (assayed by its amidolytic activity) was found in 64 normotensive workers who had been exposed to cadmium for 11 years on average and whose cadmium concentrations in urine ranged from 2.2 to 33.1 micrograms/g creatinine. The mean (geometric) urinary kallikrein activity (in U/g creatinine) amounted to 0.52 (range 0.11-1.90) in the control group (n = 193) against 0.39 (range 0.10-1.03) in the cadmium group, and the prevalence of abnormally low activity levels (less than or equal to 0.20 U/g creatinine) amounted to 17.2% in the cadmium group against 5.2% in the control group. A reduction of aldosterone release (aldosterone in urine) associated with an increased natriuresis was also observed. This might constitute a compensatory mechanism maintaining blood pressure in the normal range. These biological effects of cadmium were not reversible after removal from exposure. This study indicates that cadmium can induce an irreversible toxic effect in the distal nephron. It also suggests that an excessive cadmium body burden alone may not be sufficient to induce hypertension, but in individuals whose blood pressure regulation may be impaired by other factors cadmium could stimulate the development of hypertension. This study also supports the recommendation to prevent hypertensive subjects from being exposed to cadmium. There was no indication that moderate exposure to mercury vapour (n = 53; mercury in urine, range 11-224 micrograms/g creatinine; average duration of exposure: six years) or to inorganic lead (n = 23; lead in blood, range 40-67 micrograms/100 ml; average duration of exposure: eight years) was associated with a reduction of kallikrein production by the kidney.  相似文献   
70.
Hepatitis B screening in a New York City obstetrics service.   总被引:1,自引:1,他引:0       下载免费PDF全文
A cross-sectional chart review study was performed of hepatitis B virus (HBV) surface antigen screening of 532 women admitted to a New York City hospital obstetrics service from 1984 to 1985. Comparison of serologic results to risk factors for hepatitis B revealed that women born outside the United States and those with a positive test for or history of a sexually transmitted disease were more likely to be infected with HBV. Obstetric clinics with large immigrant populations should consider screening all patients for HBV.  相似文献   
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