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Zhaoxia LiuChunsheng Li MM Junyuan WuCaijun Wu MM Guichen Zhang MM 《The Journal of emergency medicine》2011
Background: Restoration of spontaneous circulation after cardiopulmonary resuscitation in cardiac arrest patients does not always signal a completely successful outcome. Functional deficiencies of the nervous system are found in many survivors of cardiac arrest. Objectives: To study the effects of dopamine-induced elevated blood pressure on the hemodynamics, oxygen metabolism, and cerebral resuscitation in different perfusion conditions in a resuscitated animal model. Methods: There were 18 pigs included in the study. Ventricular fibrillation (VF) was induced with a programmed electrical stimulation device. After 4 min of untreated ventricular fibrillation followed by 9 min of CPR, 12 animals were resuscitated successfully, and were then randomly assigned to either the study group (dopamine group) or the control group (normal perfusion group). All animals in the two groups received normal saline through continuous intravenous guttae for 4 h at a rate of 15 mL/kg/h. In the study group, dopamine was added to raise the animals' blood pressure. Four hours of intensive monitoring was performed for all study animals. Finally, 24-h evaluation of neurological function was conducted in surviving animals in accordance with the standard of the Cerebral Performance Category Score. Results: In animals in the dopamine group, the cardiac output, mean aortic pressure, coronary perfusion pressure, oxygen delivery, and oxygen consumption were higher than those found in the animals in the normal perfusion group (p < 0.05). Oxygen metabolism was remarkably improved in animals in the dopamine group. Furthermore, cerebral perfusion was better in the dopamine group than in the control group and thus, results of the evaluation of nervous system function were better in animals treated with dopamine (p < 0.05). Conclusions: Dopamine improved systemic perfusion, cerebral blood supply, and oxygen metabolism after successful resuscitation from VF in a porcine model. All of these factors have profound effects on the cerebral resuscitation. 相似文献
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Epstein-Barr virus lymphoproliferation after bone marrow transplantation 总被引:16,自引:7,他引:16
We review 15 cases of secondary B-cell lymphoproliferative disorders that occurred among 2,475 patients who received allogeneic bone marrow transplants (BMTs) at the Fred Hutchinson Cancer Research Center (Seattle) between 1969 and 1987. The histopathologic findings in 14 of the 15 patients spanned a wide spectrum of lymphoproliferative lesions. One patient had features characteristic of angioimmunoblastic lymphadenopathy. Epstein-Barr virus (EBV) genomic sequences were identified by Southern blot analysis in each of the 13 patients evaluated. Ten of the 12 lesions evaluated originated in donor cells. In two patients, who had mixed chimerism after transplantation, the lesions originated in host cells. The combined evidence from immunoglobulin light chain staining and the analysis of immunoglobulin heavy chain gene rearrangement indicated that the lesions in most patients represented polyclonal proliferations that gave rise to clonal subpopulations. The results indicate an overall actuarial incidence of 0.6% for this complication in BMT recipients. Anti-CD3 monoclonal antibody (MoAb) treatment of acute graft-v-host disease (GVHD) and T cell depletion of the donor marrow were statistically significant risk factors, and GVHD appeared to play a contributing role, particularly in the setting of human leukocyte antigen (HLA) disparity. Two patients had no identifiable risk factors. Prophylaxis or treatment with acyclovir had no detectable effect in the patients; all but two died with uncontrolled lymphoproliferation. 相似文献
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Objective: This was a retrospective study designed to examine the relationship between inpatient neuropsychological status and future utilization costs. Methods: We completed a retrospective chart review of 280 patients admitted to a large academic medical center who were referred for bedside neuropsychological evaluation. Patients were grouped based on neuropsychological recommendation regarding level of supportive needs post-discharge (low, moderate, high). Level of support was used as a gross surrogate indicator of cognitive status in this heterogeneous sample. We also included patients who refused assessment. Outcome variables included time to readmission, number of emergency department visits, inpatient admissions, length of hospitalization, and total costs of hospitalizations, 30 days and 1 year following discharge. Results: Multivariate analysis indicated patients who refused assessment had higher inpatient service utilization (number of ED visits, number of admissions, and total cost of hospitalization) compared to those with moderate needs. Also, high needs patients had higher total cost of hospitalization at 1 year, and those with low needs used the ED more, compared to those with moderate needs. Conclusions: Our findings replicate prior studies linking refusal of neuropsychological evaluation to higher service utilization costs, and suggest a nonlinear relationship between cognitive impairment severity and future costs for medical inpatients (different groups incur different types of costs). Results preliminarily highlight the potential utility of inpatient neuropsychological assessment in identifying patients at risk for greater hospital utilization, which may allow for the development of appropriate interventions for these patients. 相似文献
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OBJECTIVE: To assess the effect of providing free health care services to low-income adults. METHODS: We measured access to primary care services by enrollees with 4 chronic medical conditions in the General Relief Health Care Program (GRHCP), a program designed for adults receiving General Relief (GR). Implemented by the Los Angeles County Health Department in October 1995, the GRHCP is composed of private and public health care facilities. As adults registered for GR, they were asked to complete a baseline health survey, were enrolled in the GRHCP, and assigned a health care provider. A total of 8520 surveys were completed between September and November 1996 (98% response rate). The analyses of this article are limited to individuals (N = 2164) who reported a history of hypertension, diabetes mellitus, a nonresolving cough, or substance dependence. We reviewed medical records to determine whether new GR recipients had visited their designated GRHCP provider within 4 months of enrollment and used multivariate logistic regression to assess the effect of individual patient factors on the use of free health care. RESULTS: A total of 17% of individuals visited their assigned GRHCP provider within 4 months of enrollment. In multivariate analysis, patients were more likely to have made a visit if they were younger than 50 years, were female, were Asian/Pacific Islander, reported needing to see a physician, or had seen a physician within 12 months. CONCLUSIONS: It is not sufficient to merely supply the name and address of a health care provider to this population. More aggressive efforts should be attempted to increase utilization of services for patients with medical conditions responsive to ambulatory care. 相似文献
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Chronic graft-versus-host disease in 52 patients: adverse natural course and successful treatment with combination immunosuppression 总被引:18,自引:26,他引:18
Sullivan KM; Shulman HM; Storb R; Weiden PL; Witherspoon RP; McDonald GB; Schubert MM; Atkinson K; Thomas ED 《Blood》1981,57(2):267-276
Fifty-two of 175 (30%) survivors of allogeneic marrow transplantation developed chronic graft-versus-hose diseases (GVHD). Five with limited chronic GVHD had an indolent clinical course with involvement of only the skin and liver. Forty-seven with extensive chronic GVHD had an unfavorable multiorgan disorder that resembled several autoimmune diseases. Thirteen patients with extensive disease (group I) were not treated and only 2 survive with Karnofsky scores >- 70%. Mortality resulted from infections and morbidity from sica syndrome, pulmonary and hepatic insufficiency, scleroderma-like skin disease, and contractures. Another 13 (group II) received a median of 8 mo prednisone and/or a brief course of antithymocyte globulin, and 3 survive without disability. The other 21 (group III) were treated with a combination of prednisone (1.0 mg/kg/q.o.d.) and either cyclophosphamide, procarbazine, or azathioprine (all 1.5 mg/kg/day) for a median of 13 mo. Combination therapy was well tolerated with only modest myelotoxicity. Fifteen in group III had a good and 4 a fair response to treatment while 2 with no response died. Azathioprine and prednisone was the most effective regimen. All therapy has been discontinued in 12 group III patients: GVHD returned in 5 (including 2 who died in spite of retreatment) while 7 remain free of GVHD for a median of 11 (range 6-30) mo observation. Only I group III survivor is disabled and 16 of the original 21 are alive 2-4 yr after transplant with Karnofsky scores of 70%-100%. Thus, combination immmunosuppression appears to favorably affect and, in some cases, premanently arrest the adverse natural course of extensive chronic GVHD. 相似文献
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The role of fungal spores in thunderstorm asthma 总被引:2,自引:0,他引:2
STUDY OBJECTIVES: To document the existence and investigate the etiology of "thunderstorm asthma," which has been reported sporadically over the past 20 years. DESIGN: We assessed the relationship between thunderstorms, air pollutants, aeroallergens, and asthma admissions to a children's hospital emergency department over a 6-year period. RESULTS: During thunderstorm days (n = 151 days) compared to days without thunderstorms (n = 919 days), daily asthma visits increased from 8.6 to 10 (p < 0.05), and air concentrations of fungal spores doubled (from 1,512 to 2,749/m(3)), with relatively smaller changes in pollens and air pollutants. Daily time-series analyses across the 6 years of observation, irrespective of the presence or absence of thunderstorms, demonstrated that an increase in total spores, equivalent to its seasonal mean, was associated with a 2.2% (0.9% SE) increase in asthma visits. CONCLUSIONS: Our results support a relationship between thunderstorms and asthma, and suggest that the mechanism may be through increases in spores that exacerbate asthma. Replication in other climates is suggested to determine whether these findings can be generalized to other aeroallergen mixes. 相似文献