The Journal of thoracic and cardiovascular surgery
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J. Thorac. Cardiovasc. Surg. · Jun 1999
Randomized Controlled Trial Clinical TrialA randomized double-blind study of the effect of triiodothyronine on cardiac function and morbidity after coronary bypass surgery.
Although triiodothyronine deficiency has been described after cardiopulmonary bypass, data supporting its use have been conflicting. A double-blind, randomized, placebo-controlled study was undertaken to further define the effect of triiodothyronine on hemodynamics and outcome after coronary artery bypass grafting. ⋯ Parenteral triiodothyronine given after crossclamp removal during elective coronary artery bypass grafting significantly improved postoperative ventricular function, reduced the need for treatment with inotropic agents and mechanical devices, and decreased the incidence of myocardial ischemia. The incidence of atrial fibrillation was slightly decreased, and the need for postoperative pacemaker support was reduced.
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J. Thorac. Cardiovasc. Surg. · Jun 1999
A novel sialyl Lewis X analog attenuates cerebral injury after deep hypothermic circulatory arrest.
The initial step in the inflammatory process, which can be initiated by cardiopulmonary bypass and by ischemia/reperfusion, is mediated by interactions between selectins on endothelial cells and on neutrophils. We studied the effects of selectin blockade using a novel Sialyl Lewis X analog (CY-1503) on recovery after deep hypothermic circulatory arrest in a piglet model. ⋯ Blockade of selectin adhesion molecules by saturation with a Sialyl Lewisx analog accelerates recovery after 100 minutes of deep hypothermic circulatory arrest in a piglet survival model.
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J. Thorac. Cardiovasc. Surg. · Jun 1999
Oxygenation strategy and neurologic damage after deep hypothermic circulatory arrest. II. hypoxic versus free radical injury.
Laboratory studies suggest that myocardial reperfusion injury is exacerbated by free radicals when pure oxygen is used during cardiopulmonary bypass. In phase I of this study we demonstrated that normoxic perfusion during cardiopulmonary bypass does not increase the risk of microembolic brain injury so long as a membrane oxygenator with an arterial filter is used. In phase II of this study we studied the hypothesis that normoxic perfusion increases the risk of hypoxic brain injury after deep hypothermia with circulatory arrest. ⋯ In the setting of prolonged deep hypothermia and circulatory arrest with membrane oxygenators, normoxic cardiopulmonary bypass significantly increases histologically graded brain damage with respect to hyperoxic cardiopulmonary bypass. Near-infrared spectroscopy suggests that the mechanism is hypoxic injury, which presumably overwhelms any injury caused by increased oxygen free radicals.
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J. Thorac. Cardiovasc. Surg. · Jun 1999
Oxygenation strategy and neurologic damage after deep hypothermic circulatory arrest. I. Gaseous microemboli.
Recent studies suggest that myocardial reperfusion injury is exacerbated by free radicals when pure oxygen is used during cardiopulmonary bypass. Partial replacement of the oxygenator gas mixture with nitrogen, however, such as has already been adopted clinically in many centers, could increase the risk of gaseous nitrogen microembolus formation and therefore of brain damage because of the low solubility of nitrogen, particularly under conditions of hypothermia. ⋯ Gaseous microemboli are increased with normoxic perfusion, but this is only important if a bubble oxygenator without a filter is used.