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31.
K R Weeks K Chatterjee S Block J M Matloff H J Swan 《The Journal of thoracic and cardiovascular surgery》1976,71(2):250-252
Cardiac tamponade may be a difficult clinical diagnosis in the early postoperative period in patients undergoing open-hear surgery, particularly when the anterior or lateral pericardium is left open. Bedside monitoring of intracardiac pressures and determination of a "pressure plateau" between right atrial, right ventricular diastolic, pulmonary arterial diastolic, and pulmonary capillary wedge pressures are useful in the early diagnosis of cardiac tamponade. The value of such hemodynamic monitoring in the diagnosis and treatment of cardiac tamponade in three patients with aorta-coronary artery bypass surgery in the early postoperative period is reported. Appropriate therapy, carried out on the basis of these studies, minimized the occurrence of further morbidity or possible death. 相似文献
32.
STUDY DESIGN: A case of synergistic necrotizing gangrenous fasciitis after spinal surgery is reported. OBJECTIVES: To describe this unusual complication, explain the rationale of treatment, and increase awareness of this serious postoperative complication. SUMMARY OF BACKGROUND DATA: Although several cases of postoperative synergistic necrotizing fasciitis have been reported, there are no previously reported cases of this condition after spinal surgery. METHODS: A rapidly progressive necrotizing spinal wound infection after fusion for degenerative disc disease was treated in a 39-year-old man. RESULTS: The infection was successfully treated with serial debridements, appropriate antibiotics, and hyperbaric wound oxygenation. CONCLUSIONS: The authors suggest adherence to the fundamental principles of treatment including radical surgical debridement and appropriate antibiosis for necrotizing gangrene after spinal surgery. In evaluation of aggressive spinal wound infections, diagnosis of synergistic necrotizing fasciitis should be kept in mind. Although hyperbaric wound oxygenation was implemented as an adjunct and appeared to aid in controlling the infection, its effect on outcome is not clear. 相似文献
33.
3D MR DSA: effects of injection protocol and image masking 总被引:3,自引:0,他引:3
Frayne R Grist TM Swan JS Peters DC Korosec FR Mistretta CA 《Journal of magnetic resonance imaging : JMRI》2000,12(3):476-487
The purpose of this study was to investigate the effect on three-dimensional (3D) magnetic resonance digital subtraction angiography (MR DSA) images of various injection protocol parameters (ie, injection order, volume, and rate), as well as image masking. The pelves of 10 normal volunteers were scanned using seven different contrast agent volume/injection rate combinations. Subtraction of a precontrast mask image resulted in vascular image contrast improvements of between 4.0 and 7.7 times. Image quality and smaller vessel image contrast in the masked data decreased with increasing injection number. Data acquired with a high (0.150 mmol kg(-1)) volume yielded the highest quality images, although only small nonsignificant differences in image quality and large vessel conspicuity were found between images obtained using the high and medium (0.075 mmol kg(-1)) volumes. Images acquired with a low (0. 038 mmol kg(-1)) volume, while of lower image contrast, were judged to be of reasonable quality, especially when acquired as the first or second injection. Injection rate (1 ml s(-1), 2 ml s(-1), and 4 ml s(-1)) was not found to affect the images significantly, although selection of an injection rate that gave an injection duration of approximately 10 seconds tended to give better vascular image contrast. Based on these data, a series of escalating volumes for multi-injection examination is proposed. J. Magn. Reson. Imaging 2000;12:476-487. 相似文献
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Margaret Wrensch Ph.D. Shanna Swan Ph.D. Peter J. Murphy Ph.D. Jane Lipscomb Ph.D. Kathleen Claxton M.A. David Epstein M.A. 《Archives of environmental & occupational health》2013,68(4):210-216
We recently concluded that exposure to solvent-contaminated drinking water was an unlikely explanation for observed excesses of adverse pregnancy outcomes during 1980–1981 in the Los Paseos neighborhood of Santa Clara County, California, because these excesses were not observed in an adjacent exposed area. The validity of this conclusion depends on the assumption that the two areas had comparable exposure. Using quantitative methods to model movement of the solvent leak plume and water flow within the distribution system, we estimated that women with adverse outcomes were no more likely to have received contaminated water than women with normal live births. These results strengthen the conclusion that exposures to water from the contaminated well were not responsible for the excess of adverse outcomes observed in the Los Paseos area. 相似文献
37.
Cory P. Daignault Edwin L. Palmer James A. Scott John S. Swan Gilbert H. Daniels 《Nuclear Medicine and Molecular Imaging》2015,49(3):217-222
A Schmorl’s node is a common incidental finding encountered during radiologic imaging. Despite the vertebral body being a common site of metastatic disease, a lytic lesion adjacent to an endplate with typical imaging features can often confidently be called a Schmorl’s node. This is a case report of a patient with a single well-defined FDG-avid papillary thyroid carcinoma metastasis to the spine that had imaging findings characteristic of a Schmorl’s node on CT and MRI. This case is important to consider as it demonstrates that the imaging characteristics of metastatic disease and Schmorl’s nodes can overlap. 相似文献
38.
Harold S. Javitz Janet Brigham Christina N. Lessov-Schlaggar Ruth E. Krasnow & Gary E. Swan 《Addiction (Abingdon, England)》2009,104(6):1027-1035
Aim To examine whether Rasch modeling would yield a unidimensional withdrawal sensitivity measure correlating with factors associated with successful smoking cessation.
Design The psychometric Rasch modeling approach was applied to estimate an underlying latent construct (withdrawal sensitivity) in retrospective responses from 1644 smokers who reported quitting for 3 or more months at least once.
Setting Web-based, passcode-controlled self-administered computerized questionnaire.
Participants Randomly selected convenience sample of 1644 adult members of an e-mail invitation-only web panel drawn from consumer databases.
Measurements Lifetime Tobacco Use Questionnaire, assessing tobacco use across the life-span, including demographics and respondent ratings of the severity of withdrawal symptoms experienced in respondents' first and most recent quit attempts lasting 3 or more months.
Findings Rasch-modeled withdrawal sensitivity was generally unidimensional and was associated with longer periods of smoking cessation. One latent variable accounted for 74% of the variability in symptom scores. Rasch modeling with a single latent factor fitted withdrawal symptoms well, except for increased appetite, for which the fit was marginal. Demographic variables of education, gender and ethnicity were not related to changes in sensitivity. Correlates of greater withdrawal sensitivity in cessation attempts of at least 3 months included younger age at first quit attempt and indicators of tobacco dependence.
Conclusion The relationship between tobacco dependence symptoms and Rasch-model withdrawal sensitivity defines further the relationship between sensitivity and dependence. The findings demonstrate the utility of modeling to create an individual-specific sensitivity measure as a tool for exploring the relationships among sensitivity, dependence and cessation. 相似文献
Design The psychometric Rasch modeling approach was applied to estimate an underlying latent construct (withdrawal sensitivity) in retrospective responses from 1644 smokers who reported quitting for 3 or more months at least once.
Setting Web-based, passcode-controlled self-administered computerized questionnaire.
Participants Randomly selected convenience sample of 1644 adult members of an e-mail invitation-only web panel drawn from consumer databases.
Measurements Lifetime Tobacco Use Questionnaire, assessing tobacco use across the life-span, including demographics and respondent ratings of the severity of withdrawal symptoms experienced in respondents' first and most recent quit attempts lasting 3 or more months.
Findings Rasch-modeled withdrawal sensitivity was generally unidimensional and was associated with longer periods of smoking cessation. One latent variable accounted for 74% of the variability in symptom scores. Rasch modeling with a single latent factor fitted withdrawal symptoms well, except for increased appetite, for which the fit was marginal. Demographic variables of education, gender and ethnicity were not related to changes in sensitivity. Correlates of greater withdrawal sensitivity in cessation attempts of at least 3 months included younger age at first quit attempt and indicators of tobacco dependence.
Conclusion The relationship between tobacco dependence symptoms and Rasch-model withdrawal sensitivity defines further the relationship between sensitivity and dependence. The findings demonstrate the utility of modeling to create an individual-specific sensitivity measure as a tool for exploring the relationships among sensitivity, dependence and cessation. 相似文献
39.
M Norell D Lythall G Coghlan A Cheng S Kushwaha J Swan C Ilsley A Mitchell 《British heart journal》1992,67(1):53-56
OBJECTIVE--To evaluate a clinic set up specifically to assess patients with recent onset chest pain, particularly those presenting with a normal resting electrocardiogram. DESIGN--Retrospective review of case notes. SETTING--Cardiac department of a tertiary referral cardiothoracic centre. PATIENTS--250 consecutive patients with recent onset chest pain seen within 24 hours of general practitioner referral. OUTCOME MEASURES--Clinical diagnosis and management. RESULTS--40% of patients were seen within seven days of the onset of symptoms. Twenty seven per cent had non-cardiac symptoms and could be discharged while 60% were considered to have cardiac pain. Sixty six patients (26%) were admitted directly from the clinic and 48 of these underwent coronary angiography within three weeks. Seventy patients (28%) have so far undergone intervention (angioplasty or coronary artery surgery), 22 within one month of presentation. One hundred and nine patients (44%) presented with a normal resting electrocardiogram, 21 of whom were considered to have unstable angina. Forty one of these patients were investigated of whom 37 were found to have significant coronary disease and 26 have undergone intervention. CONCLUSIONS--This experience highlights the inadequacy of a routine electrocardiogram reporting service in patients with recent onset of chest pain. An alternative facility offering immediate and complete cardiac assessment produced patient benefit with early diagnosis and intervention. Investigation of these patients, however, accounted for 5% of cardiac catheterisation laboratory throughput; this was a significant additional and unscheduled workload. 相似文献
40.
Alternative referent standards for cardiac normality. Implications for diagnostic testing 总被引:1,自引:0,他引:1
A Rozanski G A Diamond J S Forrester D S Berman D Morris H J Swan 《Annals of internal medicine》1984,101(2):164-171
The radionuclide ventriculographic exercise response was evaluated in three patient populations representing alternative referent standards for cardiac normality: patients with normal coronary arteriograms, healthy volunteers, and uncatheterized patients with a low probability of coronary artery disease. Disease probability was determined by Bayesian analysis of age, sex, symptoms, and the results of cardiac fluoroscopy, exercise electrocardiography, or thallium scintigraphy. A wide range of ventriculographic responses was noted in the 62 catheterized normal patients; 21 (34%) had an abnormal ejection fraction response and 22 (35%) had an abnormal wall motion response. In contrast, the ejection fraction and wall motion responses were normal in the 9 volunteers. In 90 patients (18 catheterized and 72 uncatheterized) who had low disease probability (less than 1%), abnormal responses were rare; the ejection fraction response was abnormal in only 7% and the wall motion response was abnormal in 8%. Thus, these three populations are not equivalent referent standards of normality. Volunteers and patients with low disease probability provide too strict a standard, and their use can overestimate test specificity; catheterized normal patients, on the other hand, provide too lenient a standard, and their use can underestimate test specificity. 相似文献