Journal of cardiothoracic and vascular anesthesia
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J. Cardiothorac. Vasc. Anesth. · Aug 1999
ReviewAnticoagulation and anticoagulation reversal with cardiac surgery involving cardiopulmonary bypass: an update.
Accelerated thrombin generation is central to the development of hemostatic abnormalities during cardiopulmonary bypass (CPB) that are associated with both thromboembolic complications and serious, abnormal bleeding. Thrombin not only converts fibrinogen to fibrin, but also activates platelets and coagulation factors V, VIII, and XI and causes release of von Willebrand factor from vascular endothelium. Thrombin can also downregulate the hemostatic system by inducing formation of platelet inhibitory agents, such as nitric oxide and prostacyclin, and release of tissue plasminogen activator, facilitating activation of protein C, and releasing tissue factor pathway inhibitor. ⋯ Administration of heparin doses higher than those generally recommended, as guided by predetermined, patient-specific whole blood heparin concentration measurements during bypass, can reduce excessive thrombin-mediated consumption of platelets and coagulation factors as well as post-CPB blood loss and blood component transfusions. New modalities of improving suppression of excess thrombin generation during CPB include use of heparin-bonded CPB circuits, heparin cofactor II or related analogs, supplemental antithrombin III, direct thrombin inhibitors (eg, hirudin, argatroban), and inhibitors of the contact and tissue factor pathways. The safety and efficacy of these approaches remains to be established by additional, appropriately powered, prospective studies.
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J. Cardiothorac. Vasc. Anesth. · Aug 1999
Support of mean arterial pressure during tepid cardiopulmonary bypass: effects of phenylephrine and pump flow on systemic oxygen supply and demand.
To examine the effects of phenylephrine infusion and increases in pump flow on systemic oxygen supply and demand when they are used to support mean arterial pressure (MAP) during cardiopulmonary bypass (CPB). ⋯ During CPB with conventional flow rates, DO2 is decreased. Supporting MAP with increases in pump flow better maintains DO2 than the administration of an alpha-agonist.
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J. Cardiothorac. Vasc. Anesth. · Aug 1999
Etiology and incidence of brain dysfunction after cardiac surgery.
The frequency and severity of central nervous system complications in patients undergoing cardiopulmonary bypass (CPB) may be greater than previously thought, particularly in the older population. The risks of embolic neurologic complications and stroke in the population older than 70 years from a severely atherosclerotic ascending aorta are well documented. Moreover, while the majority of CPB patients do not experience perioperative stroke, a high incidence of more subtle central nervous system dysfunction has been demonstrated to persist for up to 1 year after surgery. ⋯ Aprotinin, a serine protease inhibitor, has been found in two separate, randomized, placebo-controlled trials to significantly lower incidences of perioperative stroke. Further study to develop therapeutic and preemptive strategies for prevention of brain injury is required, especially in the elderly. Aprotinin and other modalities aimed at suppressing the inflammatory response to CPB may offer hope because they act to suppress injury-provoking enzymes and leukocyte activation that are, in part, responsible for organ system dysfunction following CPB.
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J. Cardiothorac. Vasc. Anesth. · Aug 1999
Comparative Study Clinical Trial Controlled Clinical TrialComparison of cardiac output assessed by pulse-contour analysis and thermodilution in patients undergoing minimally invasive direct coronary artery bypass grafting.
To investigate the precision and accuracy of continuous pulse contour cardiac output (PCCO) compared with intermittent transcardiopulmonary (TCPCO) and pulmonary artery thermodilution (TDCO) measurements in patients undergoing minimally invasive coronary bypass surgery (MIDCAB). ⋯ The results of the present study show that compared with thermodilution CO, pulse contour analysis enables accurate measurement of continuous CO in patients undergoing MIDCAB.