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排序方式: 共有2213条查询结果,搜索用时 11 毫秒
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F.Andrew Gaffney Jui-Chin Lin Ronald M. Peshock Larry Bush L.Maximilian Buja 《The American journal of cardiology》1983,52(5):607-609
Several agents are used as echocardiographic contrast agents, but their unreliability discourages routine clinical use. Studies from the early 1960s suggest that dilute hydrogen peroxide (H2O2) is a safe intravascular agent. Its use was evaluated in contrast echocardiography. To obtain dense opacification reliably, H2O2 (3%) was passed through a sterile 0.2 μ Millipore filter and diluted with heparinized saline solution to make a 0.1 to 0.2% solution. A drop of blood was withdrawn from an indwelling peripheral venous needle into a syringe containing 0.5 to 2.0 ml of the dilute H2O2 and the contents injected. Studies in dogs, normal adults and 36 patients with noncyanotic congenital and acquired cardiac disorders produced dense opacification with no complications. In vitro mixture of H2O2 (0.3%) with leukocyte-poor blood or plasma produced only a few microbubbles, while addition to whole blood or buffy coat produced many, suggesting a role for leukocyte peroxidase. H2O2 contrast echocardiography is simple, inexpensive, and reliably provides dense, sustained opacification. This study and previous studies suggest that intravenous injection of 0.2% H2O2 can be done safely. Great caution should be exercised in patients with severe pulmonary hypertension or large right-to-left shunts because little clinical experience with H2O2 is available. 相似文献
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The surgical decision in tetralogy of Fallot: weighing risks and benefits with decision analysis 总被引:1,自引:0,他引:1
The preferred management of the symptomatic infant less than 2 years of age with tetralogy of Fallot remains unsettled. In this study decision analysis was used to assess the risks and benefits of three courses of action: (1) primary intracardiac repair; (2) palliative operation in infancy and delayed intracardiac repair; and (3) treatment with propranolol in infancy and delayed intracardiac repair. For each action the likelihood was determined of three possible outcomes for the patient: (1) death, (2) poor surgical result, or (3) good surgical result. Each outcome was associated with an estimated life expectancy. The best action was defined as that resulting in the longest life expectancy. With use of previously reported data and those from experience at one institution, a range of probabilities was estimated for death before operation, surgical mortality, success of propranolol treatment and hemodynamic result of operation. The choice of action was affected most by the mortality of primary intracardiac repair and the likelihood of a good hemodynamic result from intracardiac repair. Less important factors were the outcome of a palliative operation and the likelihood of success with propranolol therapy. It was found that in the institution studied if the mortality rate of primary intracardiac repair is 10 percent or less, intracardiac repair should be performed; otherwise propranolol treatment, which allows delay in intracardiac repair, should be selected. Both alternatives are preferable to palliative operation. With decision analysis, the clinician can use probabilities and life expectancy appropriate to a given clinical setting in determining the best management for the infant with tetralogy of Fallot. 相似文献
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Nicole Villafane-Ferriol George Van Buren Jose E. Mendez-Reyes Amy L. McElhany Nader N. Massarweh Eric J. Silberfein Cary Hsu Hop S. Tran Cao Carl Schmidt Nicholas J. Zyromski Mary E. Dillhoff Alexandra Roch Evelyn Oliva Alexander C. Smith Qianzi Zhang William E. Fisher 《HPB : the official journal of the International Hepato Pancreato Biliary Association》2018,20(6):514-520
Background
Although used as criterion for early drain removal, postoperative day (POD) 1 drain fluid amylase (DFA) ≤ 5000 U/L has low negative predictive value for clinically relevant postoperative pancreatic fistula (CR-POPF). It was hypothesized that POD3 DFA ≤ 350 could provide further information to guide early drain removal.Methods
Data from a pancreas surgery consortium database for pancreatoduodenectomy and distal pancreatectomy patients were analyzed retrospectively. Those patients without drains or POD 1 and 3 DFA data were excluded. Patients with POD1 DFA ≤ 5000 were divided into groups based on POD3 DFA: Group A (≤350) and Group B (>350). Operative characteristics and 60-day outcomes were compared using chi-square test.Results
Among 687 patients in the database, all data were available for 380. Fifty-five (14.5%) had a POD1 DFA > 5000. Among 325 with POD1 DFA ≤ 5000, 254 (78.2%) were in Group A and 71 (21.8%) in Group B. Complications (35 (49.3%) vs 87 (34.4%); p = 0.021) and CR-POPF (13 (18.3%) vs 10 (3.9%); p < 0.001) were more frequent in Group B.Conclusions
In patients with POD1 DFA ≤ 5000, POD3 DFA ≤ 350 may be a practical test to guide safe early drain removal. Further prospective testing may be useful. 相似文献30.