The Journal of thoracic and cardiovascular surgery
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J. Thorac. Cardiovasc. Surg. · Oct 1991
Multicenter Study Clinical TrialClinical experience with the Novacor ventricular assist system. Bridge to transplantation and the transition to permanent application.
At Stanford University, a Novacor left ventricular assist system (Baxter Healthcare Corporation, Novacor Division, Oakland, Calif.) was placed as a bridge to heart transplantation in 13 patients. During the hospitalization preceding device implantation, all patients were receiving inotropic support for biventricular failure, 11 had pulmonary edema, 6 had life-threatening ventricular arrhythmias, 5 had liver dysfunction with coagulopathy, and 2 had renal failure necessitating artificial support. The mean cardiac index before implantation of the Novacor system was 1.5. ⋯ Overall, the Novacor assist system provided effective bridging to transplantation, with posttransplant survival similar to results after routine transplantation. Modifications and improvements based on this clinical experience have been made in the areas of patient selection, techniques of operative placement, postoperative management, and design of the assist system. Isolated left heart support with a fully implantable left ventricular assist system will be offered as an alternative to heart transplantation for selected patients by 1992.
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J. Thorac. Cardiovasc. Surg. · Oct 1991
Blood and brain tissue gaseous strategy for profoundly hypothermic total circulatory arrest.
Brain tissue carbon dioxide tension, pH, and oxygen tension were measured in dogs undergoing hypothermic circulatory arrest below 20 degrees C with three types of blood gas manipulation. During core cooling, dogs were given pure oxygen (group I, n = 8), 5% carbon dioxide in oxygen (group II, n = 10), or 7% carbon dioxide in oxygen (group III, n = 4). During core cooling, brain tissue carbon dioxide tension decreased significantly in group I. ⋯ Brain tissue pH fell by 0.33 to 0.35 during 60 minutes of circulatory arrest and did not recover in groups II and III. Brain tissue oxygen tension decreased significantly during the latter two thirds of the circulatory arrest period in all three groups. To reduce progressive tissue hypercapnia and acidosis during and after circulatory arrest, a more hyperventilatory manipulation of blood gases than that achieved by alpha-stat strategy was thought beneficial for core-cooling perfusion.
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J. Thorac. Cardiovasc. Surg. · Oct 1991
Randomized Controlled Trial Clinical TrialInhibition by dexamethasone of the reperfusion phenomena in cardiopulmonary bypass.
A placebo-controlled double-blind study of patients undergoing cardiopulmonary bypass was conducted, comparing the effects of dexamethasone and a placebo on the activation of the plasmatic systems and blood cells and on the postoperative course after cardiopulmonary bypass. In the placebo group two patterns of blood activation could be distinguished. From the start of bypass, blood-material interaction caused an increase in complement C3a and elastase concentration. ⋯ In the postoperative period the patients in the placebo group had hyperthermia and hypotension and required considerable intravenous fluid administration and cardiotonic treatment. The dexamethasone-treated patients, however, showed normothermia (p less than 0.01), had significantly higher blood pressures (p less than 0.01) without supportive treatment, and consequently were in the intensive care unit for a shorter period of time. We conclude that dexamethasone prevents the hemodynamic instability after cardiopulmonary bypass and thus improves the postoperative course by inhibition of the leukocyte and tissue plasminogen activator activity generated after release of the aortic crossclamp.
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J. Thorac. Cardiovasc. Surg. · Oct 1991
The influence of preoperative anticoagulation on heparin response during cardiopulmonary bypass.
The effect of preoperative anticoagulant therapy on intraoperative heparin response in patients undergoing cardiac operations was examined in a prospective study. The study included 45 patients with different preoperative anticoagulant treatments: 10 patients received treatment with phenprocoumon (a warfarin analogue) (group M), 12 patients received treatment with intravenous heparin (group Hiv), and 13 patients received treatment with subcutaneous heparin (group Hsc). The control group consisted of 10 patients who did not receive anticoagulant therapy before operation (group C). ⋯ This study suggests that patients who receive heparin therapy before operation face a high risk of insufficient anticoagulation during cardiopulmonary bypass if standard heparin doses are used. Therefore, for patients who receive preoperative heparin therapy, a larger (500 IU/kg) initial bolus of heparin is recommended before cardiopulmonary bypass. On the other hand, patients who undergo preoperative treatment with phenprocoumon receive sufficient anticoagulative effect with a heparin bolus of 250 IU/kg.(ABSTRACT TRUNCATED AT 400 WORDS)
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J. Thorac. Cardiovasc. Surg. · Sep 1991
Diagnosis and management of purulent pericarditis. Experience with pericardiectomy.
Twelve cases of purulent pericarditis seen over 6 years are described. Staphylococcus aureus was the most common causative organism (six patients), and a respiratory infection was the most common preceding illness. The chest radiograph and echocardiogram were useful pointers to the diagnosis, but the electrocardiogram was not reliable. ⋯ The importance of early diagnosis before a significant degree of cardiac tamponade occurs is noted. Although there is general agreement that surgical drainage is mandatory, the approach, methods of drainage, and extent of pericardial resection have been the subject of some discussion, and at least seven techniques are available. We conclude that pericardiectomy has a definite place in the management of purulent pericarditis.