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61.
Intraoperative or postoperative hemorrhage in the patient who has undergone an adenotonsillectomy because of an unrecognized hemostatic defect may increase morbidity and can be potentially life-threatening to the patient in what should be a "routine" procedure. Preoperative identification of occult hemostatic abnormalities, coupled with perioperative management directed at correcting the effects of the defects, should serve to reduce the incidence of this distressful complication. Routine use of preoperative laboratory screening tests for this purpose has been discouraged recently as a result of concerns over cost-effectiveness and the low predictiveness of the tests for bleeding. Our experience with the routine use of a comprehensive hemostatic laboratory screening panel--which includes a bleeding time test--in the adenotonsillectomy patient population demonstrated that 11.5% of our patients had abnormal initial screening laboratory tests; these results were ultimately attributable to occult hemostatic defects. Clinical history, the universally recommended method of preoperative hemostatic assessment, failed to detect any previously unrecognized coagulation disorder. Laboratory screening improved preoperative detection of occult hemostatic defects and allowed for appropriate alterations in perioperative care. Our results with this approach are presented, along with illustrative case histories and a discussion of the current recommendations for preoperative laboratory screening of the hemostatic system, as found in a review of the literature. 相似文献
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Utah Community Health Plan (UCHP) is one of fifteen Robert Wood Johnson Foundation Programs for the uninsured. The experience of UCHP is similar to the other nine demonstration programs for the uninsured who have actually enrolled individuals: offering premium subsidies to uninsured small employers is an ineffective way to expand coverage among the working uninsured. 相似文献
65.
Gillinov AM Casselman FP Lytle BW Blackstone EH Parsons EM Loop FD Cosgrove DM 《The Annals of thoracic surgery》1999,67(2):382-386
BACKGROUND: The purpose of this study was to determine the prevalence, outcome, and operative strategies for patients having injury to a patent left internal thoracic artery (LITA) graft to the left anterior descending coronary artery (LAD) at coronary reoperation. METHODS: Of 655 patients with a patent LITA graft to the LAD undergoing coronary reoperation from 1986 to 1997, 35 (5.3%) sustained intraoperative injury to the LITA graft. RESULTS: Strategies to restore flow to the LAD included new saphenous vein graft to the LAD in 15 patients, saphenous vein graft to the LITA stump in 7, saphenous vein graft to the LAD and repair of the LITA graft in 6, and other strategies in 7. All or part of the LITA graft to the LAD was salvaged in 20 patients (57%). Fourteen patients (40%) sustained perioperative myocardial infarction, and 3 patients died (8.6%). The 3 patients who died all had stenosis or thrombosis of the graft to the LAD documented at autopsy. CONCLUSIONS: We conclude that (1) the prevalence of injury to a patent LITA graft is 5.3%; (2) a variety of techniques can be used to restore blood flow to the LAD; and (3) ineffective revascularization of the LAD in this situation is associated with operative mortality. At primary coronary artery bypass grafting, the LITA pedicle should be positioned in the left chest away from the posterior sternal table; this strategy may minimize the risk of LITA graft injury at coronary reoperation. 相似文献
66.
Cerebellar Purkinje neurons developing in culture were treated chronically with 30 mM (140 mg%; 3-11 days in vitro) ethanol to study the actions of prolonged ethanol exposure on responses to exogenous application of AMPA, a selective agonist at the AMPA subtype of ionotropic glutamate receptors. There was no consistent difference between control and chronic ethanol-treated neurons in resting membrane potential, input resistance, or the amplitude or duration of the membrane responses to AMPA (1 or 5 microM applied by brief microperfusion) as measured using the nystatin patch method of whole cell recording. In additional studies, the Ca2+ signal to AMPA was examined using the Ca2+ sensitive dye fura-2. The mean peak Ca2+ signal elicited by 5 microM AMPA was enhanced in the dendritic region (but not the somatic region) of chronic ethanol-treated Purkinje neurons compared to control neurons. In contrast, there was no difference between control and chronic ethanol-treated neurons in the peak amplitude of the Ca2+ signal to 1 microM AMPA, whereas the recovery of the Ca2+ signals was more rapid in both somatic and dendritic regions of ethanol-treated neurons. Resting Ca2+ levels in the somatic and dendritic regions were similar between control and ethanol-treated neurons. These data show that the membrane and Ca2+ responses to AMPA in Purkinje neurons are differentially affected by prolonged ethanol exposure during development. Moreover, chronic ethanol exposure produces a selective enhancement of AMPA-evoked dendritic Ca2+ signals under conditions reflecting intense activation (i.e., 5 microM AMPA), whereas both somatic and dendritic Ca2+ signals are attenuated with smaller levels of activation (i.e., 1 microM AMPA). Because Ca2+ is an important regulator of numerous intracellular functions, chronic ethanol exposure during development could produce widespread changes in the development and function of the cerebellum. 相似文献
67.
The postpartum hospital stay has been decreasing in the United States in recent decades. Early discharge to achieve cost savings has been criticized by many inside and outside the health care community as sometimes being detrimental to the mother and infant. This article describes the efforts of the administration, nursing staff, and medical staff of a large public urban hospital to develop an alternative to the forced early discharge of mothers and infants. 相似文献
68.
Hemingway H Crook AM Dawson JR Edelman J Edmondson S Feder G Kopelman P Leatham E Magee P Parsons L Timmis AD Wood A 《Journal of public health medicine》1999,21(4):421-429
BACKGROUND: Previous studies investigating the appropriateness of invasive management of coronary disease had not reported the internal consistency of their ratings and may now be out of date. The aim of this study was to measure the influence of clinical factors on contemporary ratings of the appropriateness of coronary angiography, percutaneous transluminal coronary angioplasty (PTCA) and coronary artery bypass graft (CABG) in the Appropriateness of Coronary Revascularisation (ACRE) study. METHODS: The Delphi-RAND technique was used, in which an expert panel (four cardiologists, three cardiothoracic surgeons, a general physician and a general practitioner), meeting in 1995, rated mutually exclusive indications (n = 2178 for angiography, n = 995 for PTCA and n = 984 for CABG). The main outcome measures were the appropriateness category (inappropriate, uncertain or appropriate) for each of the three procedures and treatment preference. RESULTS: For revascularization, the strongest determinant of inappropriateness was coronary anatomy. The odds ratio (OR) for inappropriate PTCA was 10.6 (95 per cent confidence interval (CI) 4.8-23.5) for the effect of left main stem or three-vessel disease versus single-vessel disease, and for CABG it was 0.06 (95 per cent CI 0.03-0.15). The number of diseased vessels was strongly related to preference for medical, PTCA or CABG treatment (p for linear trend <0.001). Mild versus severe anginal symptoms were associated with inappropriate angiography (OR 2.0 (95 per cent CI 0.9-9.8), although this effect was stronger when only the cardiologists' ratings were considered (OR 10.1 (95 per cent CI 2.4-42.6)). CONCLUSION: These are the first UK ratings of appropriateness covering all three procedures. The associations with clinical factors provide evidence of the internal consistency of these ratings. Prospective validation of these ratings against clinical outcomes is under way in the ACRE study. 相似文献
69.
70.
Parsons CG Danysz W Bartmann A Spielmanns P Frankiewicz T Hesselink M Eilbacher B Quack G 《Neuropharmacology》1999,38(1):85-108
The present study characterized the in vitro NMDA receptor antagonistic properties of novel amino-alkyl-cyclohexane derivatives and compared these effects with their ability to block excitotoxicity in vitro and MES-induced convulsions in vivo. The 36 amino-alkyl-cyclohexanes tested displaced [3H]-(+)-MK-801 binding to rat cortical membranes with K(i)s between 1.5 and 143 microM. Current responses of cultured hippocampal neurones to NMDA were antagonized by the same compounds with a wide range of potencies (IC50s of 1.3-245 microM, at -70 mV) in a use- and strongly voltage-dependent manner (delta 0.55-0.87). The offset kinetics of NMDA receptor blockade was correlated with equilibrium affinity (Corr Coeff. 0.87 P < 0.0001). As an example, MRZ 2/579 (1-amino-1,3,3,5,5-pentamethyl-cyclohexane HCl) had similar blocking kinetics to those previously reported for memantine (K(on) 10.67 +/- 0.09 x 10(4) M(-1) s(-1), K(off) 0.199 +/- 0.02 s(-1), K(d) = K(off)/K(on) = 1.87 microM c.f. IC50 of 1.29 microM). Most amino-alkyl-cyclohexanes were protective against glutamate toxicity in cultured cortical neurones (e.g. MRZ 2/579 IC50 2.16 +/- 0.03 microM). Potencies in the three in vitro assays showed a relatively strong cross correlation (all corr. coeffs. > 0.72, P < 0.0001). MRZ 2/579 was also effective in protecting hippocampal slices against 7 min. hypoxia/hypoglycaemia-induced reduction of fEPSP amplitude in CA1 with an EC50 of 7.01 +/- 0.24 microM. MRZ 2/579 showed no selectivity between NMDA receptor subtypes expressed in Xenopus oocytes but was somewhat more potent than in patch clamp experiments-IC50s of 0.49 +/- 0.11, 0.56 +/- 0.01 microM, 0.42 +/- 0.04 and 0.49 +/- 0.06 microM on NR1a/2A /2B, /2C and 2/D, respectively. In contrast, memantine and amantadine were both 3-fold more potent at NR1a/2C and NR1a/2D than NR1a/2A receptors. All Merz amino-alkyl-cyclohexane derivatives inhibited MES-induced convulsions in mice with ED50s ranging from 3.6 to 130 mg/kg i.p. The in vivo and in vitro potencies correlated indicating similar access of most compounds to the CNS. MRZ 2/579 administered at 10 mg/kg resulted in peak plasma concentrations of 5.3 and 1.4 microM following i.v. and p.o. administration respectively, which then declined with a half life of around 170-210 min. Analysis of A.U.C. concentrations indicates a p.o./i.v. bioavailability ratio for MRZ 2/579 of 60%. MRZ 2/579 injected i.p. at a dose of 5 mg/kg resulted in peak brain extracellular fluid (ECF) concentrations of 0.78 microM (brain microdialysates). Of the compounds tested MRZ 2/579, 2/615, 2/632, 2/633, 2/639 and 2/640 had affinities, kinetics and voltage-dependency most similar to those of memantine and had good therapeutic indices against MES-induced convulsions. We predict that these amino-alkyl-cyclohexanes, which all had methyl substitutions at R1, R2, and R5, at least one methyl or ethyl at R3 or R4 and a charged amino-containing substitution at R6, could be useful therapeutics in a wide range of CNS disorders proposed to involve disturbances of glutamatergic transmission. 相似文献