The Journal of thoracic and cardiovascular surgery
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J. Thorac. Cardiovasc. Surg. · Sep 1993
Increased plasma levels of endothelin-1 after cardiopulmonary bypass in patients with pulmonary hypertension and congenital heart disease.
The plasma level of the potent vasoconstrictor endothelin-1 was measured in children who underwent cardiac operations. Forty-five patients were divided into two groups, those with a high pulmonary blood flow (HF group; n = 23) and those with a normal or low flow (NF group; n = 22). Seven blood samples were taken: immediately before cardiopulmonary bypass, immediately after removing the aortic cross-clamps, immediately after discontinuing bypass, and at 20 minutes and 3, 6, and 24 hours after termination of bypass. ⋯ In addition, a significant positive correlation was obtained between endothelin-1 3 hours after bypass and the maximum pulmonary/systemic arterial pressure ratio during the first 12 hours after operation (r = 0.86, p < 0.05). These results suggest that cardiopulmonary bypass is associated with an immediate postoperative increase in circulating endothelin and that patients who had a high pulmonary blood flow before the operation are particularly vulnerable, bypass having a more injurious effect on a lung with preexisting endothelial dysfunction. A high level of circulating endothelin may predispose to pulmonary vascular lability and pulmonary hypertensive crises in the postoperative period.
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J. Thorac. Cardiovasc. Surg. · Sep 1993
Altered pulmonary microvascular reactivity after total cardiopulmonary bypass.
Pulmonary vascular resistance is frequently elevated after cardiac operations in which cardiopulmonary bypass is used. In our study of the possible contribution of altered pulmonary microvascular reactivity to this condition, sheep were heparinized, cannulated via the aorta and right atrium, and placed on total cardiopulmonary bypass. After 90 minutes of total cardiopulmonary bypass and pulmonary arterial occlusion, the sheep were removed from cardiopulmonary bypass, and their lungs were perfused normally for 60 minutes. ⋯ Endothelium-independent responses to sodium nitroprusside and U46619 and dilation responses to adenosine were not altered after cardiopulmonary bypass. Extracorporeal circulation with continued pulmonary arterial perfusion (right heart bypass group) had no effect on microvascular responses. In conclusion, total cardiopulmonary bypass with associated reduced pulmonary perfusion causes significant alterations of endothelium-dependent pulmonary microvascular responses because of the increased release of a constrictor prostanoid substance and possibly because of reduced release of endothelium-derived relaxing factor.
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J. Thorac. Cardiovasc. Surg. · Sep 1993
Pulmonary vascular disease and operative indications in complete atrioventricular canal defect in early infancy.
Pulmonary vascular disease was morphometrically analyzed in 67 patients (mean age, 19 months) with isolated complete atrioventricular canal defect. Complete obstruction of the small pulmonary arterial lumen resulting from acute fibrous proliferation and atrophy of the peripheral arterial media, which were considered absolute operative contraindications, were characteristic in six patients with Down's syndrome. Morphometric analysis of medial thickness revealed that thinning of the media of the small pulmonary arteries is generally observed at around 6 months of age in patients with complete atrioventricular canal defect and that the media in patients who have complete atrioventricular canal defect and Down's syndrome was thinner than that in such patients without Down's syndrome. ⋯ Excluding patients with absolute operative contraindications, the scores of the index of pulmonary vascular disease in operative survivors were below 2.0 and death occurred when scores were more than 2.2. The pulmonary vascular resistances measured in room air and by the oxygen inhalation and tolazoline tests in patients with operative contraindications were more than 7.3, 3.8, and 6.6 units.m2, respectively. We thus conclude that lung biopsy should be undertaken for patients in whom pulmonary vascular resistance is beyond these values to determine the appropriateness of surgical intervention.
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J. Thorac. Cardiovasc. Surg. · Aug 1993
Comparative StudyVenovenous compares favorably with venoarterial access for extracorporeal membrane oxygenation in neonatal respiratory failure.
Traditional extracorporeal membrane oxygenation via the venoarterial route requires cannulation and ligation of the internal jugular vein and common carotid artery. Concerns about ligation of the common carotid artery prompted development of a 14F double-lumen internal jugular vein cannula for venovenous oxygenation for neonates with respiratory failure. We retrospectively compared 22 patients supported by venovenous bypass and 20 patients supported with traditional venoarterial bypass. ⋯ There were no documented neurologic injuries in the patients managed with venovenous bypass. There were no deaths in either group. Venovenous extracorporeal membrane oxygenation through a double-lumen cannula can adequately provide respiratory support for neonates with pulmonary failure and effectively avoids ligation of the common carotid artery.
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J. Thorac. Cardiovasc. Surg. · Aug 1993
Transhiatal versus transthoracic esophagectomy for esophageal cancer.
We retrospectively analyzed 238 patients with esophageal carcinoma treated between 1983 and 1991; 120 underwent transthoracic esophagectomy, and 118 underwent transhiatal esophagectomy. The two groups were statistically similar in preoperative characteristics, except that upper esophageal cancer was more frequent in the transhiatal esophagectomy group than in the transthoracic esophagectomy group (p < 0.01). The rate of postoperative complications differed significantly in wound infection (21% in patients who underwent transthoracic esophagectomy, 10% in those who underwent transhiatal esophagectomy; p < 0.05) and empyema (11% with transthoracic esophagectomy, 1% with transhiatal esophagectomy; p < 0.01). ⋯ Late complication rate was lower with transhiatal esophagectomy than with transthoracic esophagectomy (11% and 51%, respectively). There was no significant difference in actuarial survival of patients in both groups. Transhiatal esophagectomy, which can be performed in almost all levels of the esophagus, is the safer of the two operations.