RESUMO
Enhanced dietary omega-3 fatty acid consumption is thought to be associated with a reduced incidence of atherothrombotic disorders. This effect may be mediated in part through suppression of in vivo platelet activity by omega-3 fatty acids. We observed that platelet survival, a sensitive indicator of in vivo platelet activity was prolonged from 6.4 +/- 1.5 days to 7.7 +/- 1.4 days by moderate amounts of dietary omega-3 fatty acid supplementation for 6 weeks in a group of hyperlipidemic patients with preexisting, established atherothrombotic disorders. This effect on platelet survival was associated with a decrease in platelet arachidonic acid levels from 26.7 +/- 3.5% to 20.9% +/- 2.5% and a rise in platelet eicosapentaenoic and docosahexaenoic acid measurements from essentially undetectable to 2.8% +/- 1.6% and 1.9% +/- 1.0%. Plasma total cholesterol, low-density lipoprotein cholesterol, and serum apolipoprotein B levels rose significantly during the omega-3 fatty acid supplementation period. Platelet aggregation did not change. This study demonstrates that a modest amount of dietary omega-3 fatty acid supplementation can significantly effect in vivo platelet activity in a population at high risk for recurrent atherothrombotic disorders.
Assuntos
Arteriosclerose/dietoterapia , Plaquetas/fisiologia , Ácido Eicosapentaenoico/uso terapêutico , Hiperlipidemias/dietoterapia , Adulto , Idoso , Apolipoproteínas B/sangue , Arteriosclerose/sangue , Arteriosclerose/etiologia , Plaquetas/metabolismo , Colesterol/sangue , LDL-Colesterol/sangue , Feminino , Humanos , Hiperlipidemias/sangue , Hiperlipidemias/complicações , Masculino , Pessoa de Meia-Idade , RecidivaRESUMO
Angiography documented severe (greater than 75%, cross-sectional area) bilateral carotid stenotic or occlusive disease in 60 patients. One third of these patients were thought to have transient ischemic symptoms of low-flow rather than embolic etiology. Preangiographic ocular pneumoplethysmography (OPG-Gee) was obtained in all patients. Postoperative OPG studies were obtained in the 39 patients who underwent unilateral carotid surgery. In seven of the 39 patients who were operated on, bilateral procedures were performed; OPG studies were obtained after the second procedure also. Comparison of the preoperative and postoperative OPG studies provided convincing evidence that the establishment of major carotid inflow should be the primary objective in patients with severe bilateral carotid disease, and that distal extracranial-intracranial reconstruction should be reserved for patients failing to respond to augmented inflow because of deficient collateral vessels.
Assuntos
Doenças das Artérias Carótidas/cirurgia , Revascularização Cerebral , Ataque Isquêmico Transitório/cirurgia , Pressão Sanguínea , Artéria Braquial/fisiologia , Doenças das Artérias Carótidas/complicações , Humanos , Ataque Isquêmico Transitório/etiologia , Artéria Oftálmica/fisiologiaRESUMO
Red cell sodium concentration has been found to be elevated in shock. The significance of this change relative to survival and the possible sources for this increase were examined. Twenty patients in shock had red cell sodium levels compared to shock-related variables and to conditions known to increase red cell sodium levels in vitro. There was no difference noted in red cell sodium elevations between survivors and nonsurvivors. There was a highly significant correlation with transfusions of banked blood and a significant correlation with the administration of digitalis. There was no correlation with the type, duration, or severity of shock. Changes in the sodium gradients across red cell membranes in clinical shock are not good indicators of the general cellular injury of shock.