The Journal of thoracic and cardiovascular surgery
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J. Thorac. Cardiovasc. Surg. · Dec 1995
Comparative StudyMyocardial performance in elderly patients after cardiopulmonary bypass is suppressed by tumor necrosis factor.
The aim of this study was to determine whether elderly patients (aged > or = 65 years, n = 20) in comparison with younger patients (aged < or = 55 years, n = 23) demonstrate a different biochemical and hemodynamic response to coronary artery bypass operations. In the elderly group, we calculated a smaller body surface area (p < 0.01) than that in the younger group, and more female patients were included in this group (p < 0.05). ⋯ Multivariate analysis for the postoperative outcome showed that the intergroup differences in tumor necrosis factor-alpha, mean pulmonary artery pressure, and pulmonary capillary wedge pressure could be explained mainly by the difference in age between the groups and that the calculated left ventricular stroke work index difference could be explained by the difference in circulating tumor necrosis factor-alpha levels. Thus in elderly patients higher circulating endotoxin and tumor necrosis factor-alpha concentrations were detected than in younger patients, which clinically resulted in a suppressed myocardial performance.
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J. Thorac. Cardiovasc. Surg. · Nov 1995
Comparative StudyThe effect of retrograde cerebral perfusion after particulate embolization to the brain.
Neurologic injury as a consequence of cerebral embolism of either air or atherosclerotic debris during cardiac or aortic surgery is still a major cause of postoperative morbidity and mortality. While exploring various means of improving cerebral protection during complex cardiothoracic procedures, we have developed a chronic porcine model to study retrograde cerebral perfusion. We have previously demonstrated that retrograde perfusion results in a small amount of nutritive flow and provides cerebral protection that appears to be superior to simple prolonged hypothermic circulatory arrest. ⋯ At the time of planned death on day 6, half of the brain was used for recovery of embolized microspheres after digestion with 10N sodium hydroxide. The other half was submitted for histologic study. Neurologic recovery in both the antegrade and retrograde control groups appeared to be complete, although mild evidence of histologic damage was present in some animals in the retrograde control group.(ABSTRACT TRUNCATED AT 400 WORDS)
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J. Thorac. Cardiovasc. Surg. · Nov 1995
The management of tetralogy of Fallot with pulmonary atresia and diminutive pulmonary arteries.
Since September 1991, 14 consecutive patients with tetralogy of Fallot, pulmonary atresia, and diminutive pulmonary arteries have undergone staged repair. All patients had multiple aortopulmonary collateral arteries and the ductus arteriosus was absent in 11. Mean sizes of the right and left pulmonary arteries were 2.2 +/- 0.7 mm and 1.9 +/- 0.8 mm, respectively (range 0.5 to 3.0 mm). ⋯ This experience suggests that complete repair is feasible even in patients with extremely diminutive pulmonary arteries (< or = 3.0 mm). Pulmonary artery growth is facilitated by early (3 to 6 month) establishment of central pulmonary artery flow by right ventricle-pulmonary artery conduit (pulmonary arteries > 1.5 mm) or by direct ascending aorta-pulmonary artery anastomosis (pulmonary arteries < 1.5 mm). Subsequent interventional catheterization and operative procedures as required for pulmonary artery stenoses and coil embolization of collateral arteries allow continued recruitment of central pulmonary arteries and may obviate or minimize the need for unifocalization procedures.
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J. Thorac. Cardiovasc. Surg. · Nov 1995
Inhaled nitric oxide fails to confer the pulmonary protection provided by distal stimulation of the nitric oxide pathway at the level of cyclic guanosine monophosphate.
It has been suggested that inhaled nitric oxide gas may be beneficial after lung transplantation, because endogenous levels of pulmonary nitric oxide decline rapidly after reperfusion. However theoretical concerns remain about the formation of highly toxic oxidants during the quenching of nitric oxide by superoxide. To determine whether distal stimulation of the nitric oxide-cyclic guanosine monophosphate pathway at the level of cyclic guanosine monophosphate might confer the beneficial vascular effects of nitric oxide without its potential toxicities, we studied an orthotopic rat left lung transplant model. ⋯ Cyclic guanosine monophosphate decreased pulmonary vascular resistance (1.1 +/- 0.2 vs 12.1 +/- 6.3 mm Hg/ml/min, p < 0.05), improved oxygen tension (369 +/- 56 vs 82.8 +/- 48 mm Hg, p < 0.05), reduced myeloperoxidase activity (1.7 +/- 0.3 vs 3.1 +/- 0.9 delta Abs 460 nm/min, p < 0.05), and improved recipient survival (100% vs 0%, p < 0.005) compared with Euro-Collins solution alone (control group). Animals receiving inhaled nitric oxide during reperfusion did not differ from control animals with respect to any of these parameters. These data suggest that distal stimulation of the nitric oxide-cyclic guanosine monophosphate pathway at the level of cyclic guanosine monophosphate has a protective effect that is not seen with inhaled nitric oxide in the immediate pulmonary reperfusion period.