The Journal of thoracic and cardiovascular surgery
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J. Thorac. Cardiovasc. Surg. · Jun 1990
Regional cerebrovascular reactivity to carbon dioxide during cardiopulmonary bypass in patients with cerebrovascular disease.
In patients with cerebrovascular disease, hypercarbia may cause redistribution of regional cerebral blood flow from marginally perfused to well-perfused regions (intracerebral steal), as evidenced by regional cerebral blood flow studies during carotid endarterectomy. During hypothermic cardiopulmonary bypass, the pH-stat method of acid-base management produces relative hypercarbia. To determine whether pH-stat management produces relative hypercarbia. ⋯ Carbon dioxide reactivity, defined as mean global cerebral blood flow (in ml/100 gm/min) divided by arterial carbon dioxide tension (in mm Hg), was similar in the region having the lowest regional cerebral blood flow and in the brain as a whole. No patient developed evidence of an intracerebral steal at the higher arterial carbon dioxide tension. During hypothermic cardiopulmonary bypass, higher levels of arterial carbon dioxide tension, such as those associated with the pH-stat management technique, are apparently not associated with potentially harmful redistribution of cerebral blood flow in patients with cerebrovascular disease.
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J. Thorac. Cardiovasc. Surg. · Jun 1990
Postpneumonectomy empyema. The role of intrathoracic muscle transposition.
Forty-five patients (36 male and nine female) were treated for postpneumonectomy empyema. All were initially managed with the first stage of the Clagett procedure (open pleural drainage). In 28 patients with associated bronchopleural fistula the fistula was closed and reinforced with muscle transposition at the time of open drainage. ⋯ The bronchopleural fistula remained closed in 85.7% of patients (24/28). There were 19 late deaths, none related to postpneumonectomy empyema. We conclude that the Clagett procedure remains safe and effective in the management of postpneumonectomy empyema in the absence of bronchopleural fistula and that intrathoracic muscle transposition to reinforce the bronchial stump is an effective procedure in the control of postpneumonectomy-associated bronchopleural fistula.
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J. Thorac. Cardiovasc. Surg. · May 1990
Leukocyte depletion ameliorates free radical-mediated lung injury after cardiopulmonary bypass.
Activated leukocytes and oxygen free radicals have been implicated in the pathogenesis of lung injury associated with cardiopulmonary bypass. To determine whether leukocyte depletion could prevent this injury, we used a dog model simulating routine cardiac operations. Mongrel dogs (11 to 17 kg) were subjected to cardiopulmonary bypass with a bubble oxygenator and cooled to 27 degrees C. ⋯ Pulmonary function after bypass was better preserved in leukocyte-depleted animals. These data suggest that depletion of circulating leukocytes contributes to lung injury during cardiopulmonary bypass and is associated with increased oxygen radical activity, pulmonary edema, and vasoconstriction. Leukocyte depletion substantially reduced the pulmonary injury seen after cardiopulmonary bypass.
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J. Thorac. Cardiovasc. Surg. · May 1990
Latissimus dorsi dynamic cardiomyoplasty of the right ventricle. Potential for use as a partial myocardial substitute.
Full-thickness right ventricular latissimus dorsi dynamic cardiomyoplasty with the Medtronic Cardiomyostimulator (Medtronic, Inc., Minneapolis, Minn.) was performed in a chronic canine model. In one group (n = 2) the latissimus dorsi was electrically preconditioned before cardiomyoplasty. In a second group (n = 3) cardiomyoplasty was performed and the muscle was progressively stimulated, with conditioning accomplished while the latissimus dorsi was functioning on the ventricle. ⋯ Latissimus dorsi dynamic cardiomyoplasty can function as a partial myocardial replacement in a chronic canine model, apparently without preconditioning of the muscle. The degree of cardiac assist obtained with cardiomyoplasty appears to be influenced by the voltage and frequency of the stimulus applied to the muscle. Although it is unclear whether these results can be extrapolated to the left ventricle, this technique may find application in the treatment of ventricular aneurysm or ventricular tumor.
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J. Thorac. Cardiovasc. Surg. · May 1990
Clinical Trial Controlled Clinical TrialAprotinin protects platelets against the initial effect of cardiopulmonary bypass.
Remarkable improvement in hemostasis after cardiopulmonary bypass has been achieved by treatment with the proteinase inhibitor aprotinin, but the mechanism is still unclear. The present study is designed to elucidate the importance of platelet adhesive (glycoprotein Ib) or aggregatory (glycoprotein IIbIIIa) receptors on this hemostatic function in cardiopulmonary bypass and its improvement by aprotinin treatment. To determine whether the first pass of blood through the circuit or a continuous proteolytic attack is the main cause of platelet damage, we gave two different dose regimens of aprotinin treatment to patients undergoing coronary artery bypass grafting. ⋯ Although the fibrinolytic activity was effectively inhibited in both aprotinin groups, fibrinolytic activity became apparent only at the end phase of bypass in the placebo group. However, improved hemostasis was observed intraoperatively from the start of bypass and resulted in a 40% lower blood loss intraoperatively and postoperatively and consequently a 40% lower total blood requirement in the aprotinin-treated patients than in the untreated patients. Our results therefore demonstrate that the improved hemostasis during and after bypass in patients treated with aprotinin has specifically to be attributed to a preserved adhesive capacity of platelets that was affected in the first pass of blood through the cardiopulmonary bypass circuit.