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81.
The hemostatic dysfunction induced by cardiopulmonary bypass is due, in part, to a platelet dysfunction evidenced by a postoperative extension of the bleeding time; it leads to increased postoperative blood loss and morbidity. This study, which was conducted in 85 patients undergoing cardiopulmonary bypass, was designed to characterize the hematologic changes during and after cardiopulmonary bypass and to elucidate the relationships between these changes, the extension of the bleeding time, and the magnitude of the postoperative nonsurgical blood loss. Variables were measured before, during, and 2, 24, 48, and 72 hours after cardiopulmonary bypass. Univariate and multivariate analyses were performed with either the 2-hour postbypass bleeding time or the 4-hour postbypass blood loss as the dependent variables. The reversal of the extension of the bleeding time in the postoperative period was accompanied by a significant increase in the mean platelet volume and by a significant increase in the level of thromboxane B2 measured in the blood shed from the site of the bleeding time determination. The postoperative bleeding time correlated with the postoperative blood loss, and both parameters were dependent on the duration of cardiopulmonary bypass. In addition, the postoperative bleeding time correlated with the skin temperature and the plasma level of D-dimer, while the postoperative blood loss also correlated with temperature and the plasma levels of C3. These data establish a direct relationship between the postoperative bleeding time, the postoperative blood loss, and temperature. They indicate that the reversal of the postoperative extension of the bleeding time is due in part to rewarming and to the release of larger platelets into the circulation, and they suggest that hyperfibrinolysis and complement activation may play an important role in the cardiopulmonary bypass-induced platelet dysfunction.  相似文献   
82.
Preoperative characteristics of 964 patients in the Veterans Administration Cooperative Study on Valvular Heart Disease undergoing single valve replacement were examined to determine predictors of operative mortality. The operative mortality rate was 8.3% in 661 patients having isolated aortic valve disease and 7.5% in 239 patients having isolated mitral valve disease, but 12.5% in 64 patients with multivalve disease undergoing single valve replacement. For the aortic valve replacement subgroup, three-vessel coronary artery disease, left ventricular systolic pressure, prior cardiac operation, body surface area, and cardiac index were related to operative mortality. In the mitral valve replacement group, there was a strong association of operative mortality with advanced age, exertional dizziness, reduced cardiac index, left ventricular contraction grade, ST segment depression on the resting electrocardiogram, and pleural effusion. The risk of operative death for an individual patient undergoing aortic or mitral valve replacement may be estimated with the use of independent risk factors.  相似文献   
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For prognostication of aorta-coronary bypass graft patency, preoperative angiographic assessment of the recipient vessel and the regional left ventricle was compared with the intraoperative measurement of the internal diameter of the vessel and graft flow in 98 patients, in whom graft patency was evaluated at 1 year. Preoperative assessment of the recipient vessel did not correlate with the intraoperative measurement of the internal diameter or with the graft patency. Preoperative assessment of the regional left ventricular wall motion, on the other hand, was more valuable for prognosticating graft patency. Regions assessed as normal or hypokinetic had equally good graft patency, whereas akinetic or dyskinetic areas had only a 54% patency rate. Intraoperative measurement of the internal diameter of the vessel and graft flow were reliable predictors of graft patency: The larger the internal diameter and the greater the graft flow, the better the graft patency. Best surgical results can therefore be predicted when the internal diameter of the recipient vessel is 2.5 mm or more, graft flow is 100 ml/min or more, and the regional left ventricle moves well.  相似文献   
86.
A definitive surgical procedure for a giant cell tumor that combines metacarpal resection with an iliac bone graft and arthroplasty with a silicone rubber implant is proposed for the elderly patient. The results were encouraging in one patient who had a cosmetically and functionally acceptable hand and no evidence of recurrence.  相似文献   
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Changes in regional ejection fraction (rEF) of the interventricular septum following coronary artery bypass graft (CABG) surgery were examined using first-pass radionuclide ventriculography (RNVG) in patients without objective evidence of postoperative myocardial infarction (MI). One hundred and one patients had pre- (mean 6.3 days) and early postoperative (mean 8.7 days) RNVGs, and 60 of these patients had follow-up studies at 14-39 months (mean 27 months) postsurgery. Early post-CABG, mean rEF in the proximal septum was unchanged from the preoperative value (35.3%), with almost equal numbers of patients showing increased (n = 36), unchanged (n = 33) or decreased (n = 32) rEFs. In the distal septum, mean rEF increased from 47.1 to 50.7%, with more than twice as many patients having increased (n = 44) as decreased (n = 20) rEF. At late follow-up, proximal septum rEF in individual patients tended to revert to the presurgery baseline, with 72% (13/18) of regions with early decrease improved and 61% (14/23) of those with early improvement decreased. In the distal septum, rEF was less than early post-CABG in 76% (19/25) of patients with early improvement, while being improved in 27% (3/11) of those with early decrease in rEF. In the absence of MI, changes in rEF in the proximal septum early post-CABG tend to resolve over time. While global changes in cardiac systolic motion are the probable cause of many new post-CABG septal abnormalities, persistent septal dysfunction probably reflects effects of permanent damage as a result of the operative procedure.  相似文献   
90.
Pinealectomyaffectsthediurnalvariationsin2-[~(125)I]iodomelatoninbindingsitesinchickenbursaofFabriciusZhaoYing(赵瑛);PoonAMS,Pa?..  相似文献   
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