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1.
J.L. Bernat A.M. D'Alessandro F.K. Port T.P. Bleck S.O. Heard J. Medina S.H. Rosenbaum M.A. DeVita R.S. Gaston R.M. Merion M.L. Barr W.H. Marks H. Nathan K. O'Connor D.L. Rudow A.B. Leichtman P. Schwab N.L. Ascher R.A. Metzger V. Mc Bride W. Graham D. Wagner J. Warren F.L. Delmonico 《American journal of transplantation》2006,6(2):281-291
A national conference on organ donation after cardiac death (DCD) was convened to expand the practice of DCD in the continuum of quality end-of-life care. This national conference affirmed the ethical propriety of DCD as not violating the dead donor rule. Further, by new developments not previously reported, the conference resolved controversy regarding the period of circulatory cessation that determines death and allows administration of pre-recovery pharmacologic agents, it established conditions of DCD eligibility, it presented current data regarding the successful transplantation of organs from DCD, it proposed a new framework of data reporting regarding ischemic events, it made specific recommendations to agencies and organizations to remove barriers to DCD, it brought guidance regarding organ allocation and the process of informed consent and it set an action plan to address media issues. When a consensual decision is made to withdraw life support by the attending physician and patient or by the attending physician and a family member or surrogate (particularly in an intensive care unit), a routine opportunity for DCD should be available to honor the deceased donor's wishes in every donor service area (DSA) of the United States. 相似文献
2.
Paul Wexberg MD BM Richard Pacher MD Suzanne Rdler MD Katharina Kiss MD Gilbert Beran MD Michael Grimm MD Gerald Maurer MD Dietmar Glogar MD FESC 《The Journal of heart and lung transplantation》2002,21(12):583-1263
BACKGROUND: Endothelin, a peptide with strong vasoconstrictive and mitogenic properties, has been found to increase after cardiac transplantation. We therefore assessed the association between its precursor peptide, big endothelin-1, and intimal hyperplasia and coronary flow reserve after heart transplantation. METHODS: Thirty-five patients without hemodynamically significant coronary artery disease after heart transplantation were investigated: Average peak flow velocity in the left anterior descending artery (LAD) was assessed by intracoronary Doppler at baseline as well as after injection of adenosine; coronary flow reserve was calculated as a ratio of both and was corrected for patient age and baseline average peak flow velocity. Lumen, intima + media and total vessel area were measured by intracoronary ultrasound. The plasma concentration of big endothelin-1 in venous blood was determined by radioimmunoassay. RESULTS: Patients with elevated big endothelin-1 levels (>2 fmol/ml) tended to have a decreased corrected coronary flow reserve (2.60 +/- 0.9 vs 3.21 +/- 1.0, p = 0.078). They also had a significantly larger intima + media area (5.82 +/- 2.9 vs 2.37 +/- 2.9 mm(2), p = 0.004) and total vessel area (18.36 +/- 5.8 vs 12.81 +/- 4.8 mm(2), p = 0.012) than those with normal plasma concentrations. CONCLUSIONS: Our study suggests an association between elevated big endothelin-1 plasma levels and the development of intimal hyperplasia and reduction of coronary flow reserve after cardiac transplantation. 相似文献
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Hospital isolates of Enterobacter cloacae were analysed by polyacrylamide gel electrophoresis for enzyme polymorphism and the results were compared with established serotyping, phage typing and biotyping techniques. Initially, the diversity of electromorphs of 13 enzymes was determined on a representative set of 62 distinct strains. Two broad clusters of strains were found in the species, and analysis by serotype suggested a limited diversity within the most frequent O serotypes. A subset of three enzymes, lactate dehydrogenase, 6-phosphogluconate dehydrogenase, glutamate dehydrogenase and an unidentified marker, were selected and used to type groups of hospital isolates. There was good general agreement between the two systems, although the enzyme method failed to distinguish between some strains with the same serotype. This method provided useful epidemiological information and, in the absence of established typing systems, it is a practical approach to subdividing the species. 相似文献
6.
Impaired cortisol stress response in fish from environments polluted by PAHs,PCBs, and mercury 总被引:6,自引:0,他引:6
Alice Hontela Joseph B. Rasmussen Céline Audet Gaston Chevalier 《Archives of environmental contamination and toxicology》1992,22(3):278-283
The cortisol stress response to capture was investigated in two species of fish (Perca flavescens and Esox lucius) from sites polluted by high levels of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and mercury, and from reference sites in the St. Lawrence river system. Fish from the reference sites exhibited the normal elevation of serum cortisol in response to the acute stress of capture and had large pituitary corticotropes. In contrast, fish from the most polluted sites were unable to increase their serum cortisol in response to the acute stress of capture and their pituitary corticotropes were atrophied. These results suggest that a life-long exposure to chemical pollutants may lead to an exhaustion of the cortisol-producing endocrine system, possibly as a result of prolonged hyperactivity of the system. 相似文献
7.
Gaston R Vergara William F Wallace Kenneth R Bennett 《Catheterization and cardiovascular interventions》2007,69(2):300-302
Thromboembolic disease accounts for thousands of hospitalizations every year in the US. Its primary management consists of anticoagulation. However, in certain instances this may be contraindicated or not sufficient. Mechanic occlusion of the inferior vena cava (IVC) becomes then a viable alternative. In this case a 35-year-old man presented with a saddle pulmonary embolus but was unable to be anticoagulated due to intestinal bleed. A removable IVC filter was then placed. The filter spontaneously migrated into the right atrium causing severe tricuspid regurgitation, perforation of the atrial wall, and cardiac tamponade. The device was successfully retrieved percutaneously and the patient discharged from the hospital in stable condition. This case illustrates the potentially lethal complications associated with the use of IVC filters, as well as the possibility to percutaneously recover them from within the right atrium. 相似文献
8.
Atilio Migues MD Gaston Slullitel MD Anibal Vescovo MD Felipe Droblas MD Marina Carrasco MD Hugo Perrin Turenne MD 《The Journal of foot and ankle surgery》2005,44(5):1043-357
The majority of foot and ankle operations are performed on an outpatient basis and often under some form of regional anesthesia. In this prospective, randomized study of 51 patients undergoing elective unilateral forefoot procedures, we compared 2 different anesthetic techniques: the peripheral foot blockade and the popliteal sciatic nerve block. Variables assessed included the quality of surgical anesthesia, postoperative analgesia, and the incidence of postoperative complications. The anesthesia was classified as effective if it was the sole anesthetic technique for the forefoot surgery. We found successful results in both groups: 92% in the foot block group and 96% in the popliteal block group. Analysis of time required to perform the anesthetic procedure showed a significant difference between the 2 groups, with foot block being considerably faster (14.3 minutes vs 19.2 minutes for popliteal block) (P = .0078). Foot block patients demonstrated 10.96 hours of analgesia, whereas popliteal block patients exhibited 14.32 hours (P = .132). With a mean follow-up of 5.7 months, we did not find anesthesia-related complications in any of the patients. Both techniques showed a high level of safety and efficacy, with no significant difference detected between them. Our patients showed a high rate of satisfaction with both procedures (96% for foot block patients and 96.1% for popliteal block patients) and reported a good discharge disposition. These data show that both procedures are safe and effective anesthetic techniques and well suited to forefoot ambulatory surgery. 相似文献
9.
F Ricolfi P Y Gobin A Aymard F Brunelle A Gaston J J Merland 《AJNR. American journal of neuroradiology》1997,18(4):677
PURPOSETo present the clinical and radiologic features of giant perimedullary arteriovenous fistulas (GAVFs) in 12 consecutive cases and to evaluate the results of endovascular treatment.METHODSWe retrospectively reviewed the clinical and radiologic data as well as the results of balloon endovascular treatment obtained from 1980 to 1989.RESULTSGAVFs, defined as large intradural perimedullary direct arteriovenous high-flow shunts, are revealed mainly in childhood either by subarachnoid hemorrhage or by progressive neurologic disorders. MR imaging and myelography show major vascular dilatations. The angioarchitecture of GAVFs can only be assessed by selective spinal angiography. Ten patients were treated by balloon occlusion resulting in eight anatomic cures and six good clinical results. One balloon migrated to the venous side, leading to clinical deterioration.CONCLUSIONGAVF is a special subgroup of intradural perimedullary arteriovenous fistula. The endovascular approach should be the first line of treatment, with surgery reserved for special circumstances. Nondetachable balloon occlusion is a safe and efficient method for treating GAVFs. 相似文献
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