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101.
Listeria monocytogenes (LM) is one of the rare microorganisms causing peritonitis in peritoneal dialysis (PD) patients. We report a sporadic case of peritonitis caused by LM in a young female PD patient with lupus receiving corticosteroid therapy, who presented with abdominal pain, cloudy PD effluent, nausea, and conjunctivitis. The effluent showed a high PD effluent white cell count and monocytosis, and gram staining showed gram-positive bacilli in single or short chains and PD effluent culture grew LM. She was treated successfully with beta lactum antibiotics. LM peritonitis should be suspected if a patient presents with gram-positive bacilli and monocytosis in dialysis effluent.  相似文献   
102.
Background Previous research has shown that surgeons’ intraoperative non-technical skills are related to surgical outcomes. The aim of this study was to evaluate the reliability of the NOTSS (Non-technical Skills for Surgeons) behavior rating system. Based on task analysis, the system incorporates five categories of skills for safe surgical practice (Situation Awareness, Decision Making, Task Management, Communication & Teamwork, and Leadership). Methods Consultant (attending) surgeons (n = 44) from five Scottish hospitals attended one of six experimental sessions and were trained to use the NOTSS system. They then used the system to rate consultant surgeons’ behaviors in six simulated operating room scenarios that were presented using video. Surgeons’ ratings of the behaviors demonstrated in each scenario were compared to expert ratings (“accuracy”), and assessed for inter-rater reliability and internal consistency. Results The NOTSS system had a consistent internal structure. Although raters had minimal training, rating “accuracy” for acceptable/unacceptable behavior was above 60% for all categories, with mean of 0.67 scale points difference from reference (expert) ratings (on 4-point scale). For inter-rater reliability, the mean values of within-group agreement (r wg) were acceptable for the categories Communication & Teamwork (.70), and Leadership (.72), but below a priori criteria for other categories. Intra-class correlation coefficients (ICC) indicated high agreement using average measures (values were .95–.99). Conclusions With the requisite training, the prototype NOTSS system could be used reliably by surgeons to observe and rate surgeons’ behaviors. The instrument should now be tested for usability in the operating room.  相似文献   
103.
Functional activity within brain tumors: a magnetic source imaging study   总被引:6,自引:0,他引:6  
Schiffbauer H  Ferrari P  Rowley HA  Berger MS  Roberts TP 《Neurosurgery》2001,49(6):1313-20; discussion 1320-1
OBJECTIVE: To determine whether low-grade gliomas contain functional cortical activity more often than high-grade gliomas within radiologically defined abnormal tissue. METHODS: Patients with intra-axial cerebral lesions located in the vicinity of eloquent brain cortex preoperatively underwent magnetic source imaging. A dual 37-channel biomagnetometer was used to perform the imaging. Evoked magnetic fields were analyzed using the single-equivalent dipole representation to ascertain the neuronal source. Stimuli included painless tactile somatosensory stimulation of fingers, toes, and lips and auditory presentation of pure sinusoidal tones. RESULTS: A retrospective analysis of 106 nonconsecutively treated patients, who had undergone preoperative magnetic source imaging between February 1996 and December 1999, revealed that 24.5% of the patients had been at risk for neurological deficits, because functionally active tissue was located within or at the border of the tumor. Functional activity was found within the radiologically defined lesion in 18% of Grade 2 tumors, in 17% of Grade 3 tumors, and in 8% of Grade 4 tumors. CONCLUSION: The results confirm that, regardless of tumor grade, intra-axial brain tumors may involve or directly border on functional cortex. The degree of involvement of functionally viable cortex appeared greater for low-grade tumors than for high-grade lesions. On the other hand, high-grade lesions were more likely to be associated with functional cortex at their margins or within peritumoral edema. To safely maximize tumor resection, preoperative functional imaging and intraoperative electrophysiological mapping of the cerebral cortex and the white matter tracts are deemed necessary.  相似文献   
104.
OBJECT: The goal of this study was to determine whether the late neuromagnetic field elicited by simple speech sounds, which is detected by magnetoencephalography, may be used to estimate hemispheric dominance for language and to guide or constrain the intraoperative search for essential language sites. If sufficiently robust, a noninvasive method for assessing hemispheric dominance for language could reduce the necessity for amobarbital testing and the extent of intraoperative cortical stimulation-based mapping, both of which carry the risk of morbidity. METHODS: Fifteen patients undergoing surgery for tumors during which intraoperative language mapping would be performed and two additional patients in whom intracarotid amobarbital testing confirmed right-hemisphere language dominance participated. Following a primary auditory response sources of late neuromagnetic fields elicited by vowel stimuli were modeled and coregistered using magnetic resonance images to form magnetic source (MS) images. A laterality index (LI) was calculated by summing the number of equivalent current dipolar sources in the late fields detected from each hemisphere. In 14 right-handed patients, 10 displayed left asymmetric LIs (0.37 +/- 0.16. mean +/- standard error of the mean in 14 patients). For both right-hemisphere dominant patients in whom an LI was obtainable, the LI was rightward. Stimulation-mapped essential language sites were found in 7 of 15 patients. For six of these seven patients, the MS image-derived LI was leftward. CONCLUSIONS: Asymmetry in single equivalent dipole modeling of the late neuromagnetic field evoked by simple speech sounds correlates with hemispheric language dominance, although not to the degree necessary for individual clinical predictions. With further development, MS imaging of simple language tasks may be used preoperatively to predict language dominance and even to identify or constrain the intraoperative search for likely sites of essential language cortex.  相似文献   
105.
BACKGROUND: Complicated intra-abdominal infections are a common problem in surgical practice. This study compared the effectiveness of ertapenem (1 g qd) and piperacillin/tazobactam (3.375 g q6h) in the treatment of these infections. METHODS: This was a multicenter, double-blinded, randomized study conducted in patients with complicated intra-abdominal infections. Of the 535 patients screened, 500 were stratified on the basis of disease severity (Acute Physiology and Chronic Health Evaluation [APACHE] II score < or =10 or >10), then randomized (1:1) to 4-14 days of treatment with one of the regimens and six weeks of followup. Nearly all patients (N = 494) were treated. The primary endpoint was the proportion of microbiologically evaluable patients with a favorable clinical response (cure) at two weeks. Non-inferiority of ertapenem was based on a difference in response rate of <15 percentage points compared with piperacillin/tazobactam (lower bound of the 95% CI > -15). RESULTS: Of the 494 treated patients, 231 were microbiologically evaluable, with 123 and 108 patients in the ertapenem and piperacillin/tazobactam groups, respectively. Statistically similar cure rates were observed in the ertapenem (82.1%) and piperacillin/tazobactam (81.7%) groups (difference 0.3 [95% CI: -9.6, 10.5]). The pathogens isolated most frequently were Escherichia coli, Bacteroides fragilis, and Bacteroides thetaiotamicron, typical isolates associated with intra-abdominal infections. There were no statistical differences between the groups in serious drug-related clinical adverse events, drug-related clinical adverse experiences leading to study discontinuation, or mortality. CONCLUSIONS: Ertapenem was non-inferior to piperacillin/tazobactam in the cure of intra-abdominal infections caused by susceptible pathogens. Both study drugs generally were well tolerated.  相似文献   
106.

Background  

Pulmonary dysfunction following cardiac surgery is believed to be caused, at least in part, by a lung vascular injury and/or atelectasis following cardiopulmonary bypass (CPB) perfusion and collapse of non-ventilated lungs.  相似文献   
107.
Multi-detector computed tomography (MDCT) has become an alternative to coronary angiography in diagnosis of graft occlusion and stenosis after coronary artery bypass. A literature search was performed for studies comparing angiography to 8-slice, 16-slice, and 64-slice MDCT in the assessment of coronary grafts. In assessing occlusion, 14 studies produced pooled sensitivity of 97.6%, specificity of 98.5%, diagnostic odds ratio of 934.2, area under the curve of 0.996, and Q* of 0.977. Ninety-six percent of all grafts were visualized for occlusion assessment. Beta blockers, symptomatic status, and postoperative period did not significantly affect diagnostic performance. Stenosis assessment produced sensitivity of 88.7% and specificity of 97.4%. Eighty-eight percent of patent grafts could be assessed for stenosis. The diagnostic accuracy of MDCT approaches angiography for diagnosing graft occlusion and stenosis in patients with venous and arterial coronary bypass grafts. Our findings show that cardiac surgeons will need to interpret MDCT images of both native and grafted vessels soon in preparation for primary or re-do coronary bypass grafting procedures.  相似文献   
108.
Objective Changes in serum albumin may reflect systemic immunoinflammation and hypermetabolism in response to insults such as trauma and sepsis. Esophagectomy is associated with a major metabolic stress, and the aim of this study was to determine if the absolute albumin level on the first postoperative day was of value in predicting in-hospital complications. Methods A retrospective study of 200 patients undergoing esophagectomy for malignant disease at St. James Hospital between 1999 and 2005 was performed. Patients who had pre and postoperative (days 1, 3, and 7) serum albumin levels measured were included in the study. Patients were subdivided into three postoperative albumin categories <20 g/l, 20–25 g/l, >25 g/l. Logistic regression analysis was performed to calculate the odds of morbidity and mortality according to the day 1 albumin level. Results Patients with an albumin of less than 20 g/l on the first postoperative day were twice as likely to develop postoperative complications than those with an albumin of greater than 20 g/l (54 vs 28% respectively, p < 0.011). Correspondingly, these patients also had a significantly higher rate of Adult Respiratory Distress Syndrome (22 vs 5%, p < 0.001), respiratory failure (27 vs 8%, p < 0.01) and in-hospital mortality (27 vs 6% (p < 0.001). On multivariate logistic regression analysis, day 1 albumin level was independently related to postoperative complications (odds ratios, 0.89: 95%; confidence intervals, 0.83–0.96; p < 0.005). In addition, albumin <20 g/l on the first postoperative day was associated with the need for further surgery and a return to ICU. Conclusion Serum albumin concentration on the first postoperative day is a better predictor of surgical outcome than many other preoperative risk factors. It is a low cost test that may be used as a prognostic tool to detect the risk of adverse surgical outcomes.  相似文献   
109.
OBJECTIVE: This report describes the pilot of a free comprehensive national screening program for venous disease. METHODS: The screening process consisted of a venous thromboembolism (VTE) risk assessment, abbreviated duplex examination for venous obstruction and reflux, inspection for signs of chronic venous insufficiency (CVI), and an exit interview. Physicians coordinating the screenings were members of the American Venous Forum. RESULTS: Seventeen institutions screened 476 people (mean, 28 per site; range, 6 to 71). Mean age was 60 years (range, 40 to 91 years), with 78% women and 68% with a body mass index of > or =25. If placed in a situation conducive for VTE, 22 participants (5%) were low risk, 87 (18%) were moderate risk, 186 (39%) were high risk, and 179 (38%) were at very high risk. In 26 people (6%), one or more segments had venous obstruction, and 190 (40%) had one or more segments of venous reflux in the lower extremities. Varicose veins were present in 32%, edema without skin changes in 11%, skin changes attributable to venous disease in 8%, and healed or active venous stasis ulcer in 1.3% (CEAP classification 2, 3, 4, 5, and 6, respectively). Increasing age and increasing deep venous thrombosis risk score significantly correlated with increasing clinical classification, r = 0.09, P = .04, and r = 0.16, P = .0004, respectively. Those participants with reflux in one or more segments were significantly more likely to have a higher clinical classification compared with those with no reflux (P = .0001). CONCLUSION: The first comprehensive national screening for venous disease was performed. Participants were informed of their risk for VTE if placed in a situation conducive to VTE, screened for evidence of obstruction, reflux, and CVI, and empowered to share their results with their primary care provider.  相似文献   
110.
PURPOSE: To review the effects of the long QT syndrome (LQTS) in the parturient and the current anesthetic management of patients with LQTS. SOURCE: Relevant articles were obtained from a MEDLINE search spanning the years 1980-2006 and a PubMed search spanning the years 1949-2006. Bibliographies of retrieved articles were searched for additional articles. PRINCIPAL FINDINGS: The prevalence of LQTS in the developed world is one per 1,100 to 3,000 of the population. Clinically, LQTS is characterized by syncope, cardiac arrest and occasionally, by a history of seizures. The QT interval can also be prolonged by drugs, electrolyte imbalances, toxins and certain medical conditions. Long QT syndrome patients are at risk of torsades de pointes and ventricular fibrillation. Medical management aims to reduce dysrhythmia frequency. The LQTS is subdivided into different groups (LQT1-6) depending on the cardiac ion channel abnormality. Torsades can be precipitated by adrenergic stimuli such as stress or pain (LQT1 and 2), sudden noises (LQT2) or whilst sleeping (LQT3). Patients with LQTS require careful anesthetic management as they are at high risk of torsades perioperatively despite minimal data on the effects of anesthetic agents on the QT interval. While information on effects of LQTS in pregnancy is limited, the incidence of dysrhythmia increases postpartum. Isolated case reports of patients with LQTS women highlight several peripartum dysrhythmias. CONCLUSION: An understanding of LQTS and the associated risk factors contributing to dysrhythmias is important for anesthesthesiologists caring for parturients with LQTS.  相似文献   
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