Journal of cardiothoracic and vascular anesthesia
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J. Cardiothorac. Vasc. Anesth. · Apr 1993
Postoperative analgesia and sedation following pediatric cardiac surgery using a constant infusion of ketamine.
Constant rate infusions of ketamine supplemented with intermittent doses of midazolam were given postoperatively to 10 children in order to provide analgesia and sedation during mechanical ventilation after cardiac surgery as well as during weaning from the ventilator and during spontaneous breathing. The aims of the study were to determine the pharmacokinetics of ketamine and evaluate the suitability of ketamine as an analgesic and sedative in postoperative pediatric cardiac patients. The children were between one week and 30 months old. ⋯ Norketamine did not reach a steady state, but at the end of the infusion, the mean plasma concentration was higher than that of ketamine. The elimination half-life of norketamine was estimated to be 6.0 +/- 1.8 hours. Both ketamine infusion regimens were supplemented with midazolam and provided similarly acceptable analgesia and sedation during mechanical ventilation and during and after weaning from the ventilator.(ABSTRACT TRUNCATED AT 250 WORDS)
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J. Cardiothorac. Vasc. Anesth. · Apr 1993
Potential risks of high-dose epinephrine for resuscitation from ventricular fibrillation in a porcine model.
The arterial plasma concentrations and hemodynamic effects of epinephrine, 10 micrograms/kg, IV (group A, N = 8) and 50 micrograms/kg, IV (group B, N = 8) were compared in a porcine resuscitation model after 3 minutes of circulatory arrest induced by ventricular fibrillation. All animals in group A were successfully resuscitated after 4.9 +/- 2.8 minutes and 2.8 +/- 1.6 defibrillations. In group B, only 6 of 8 animals were successfully resuscitated after 6.3 +/- 1.1 minutes and 4.0 +/- 2.7 defibrillations (mean +/- SD). ⋯ Mean arterial peak epinephrine concentrations (group A 197 +/- 133 ng/mL, group B 1173 +/- 298 ng/mL) were approximately fivefold higher in group B. After resuscitation, plasma concentrations returned to baseline levels within 7 minutes in group A and 15 minutes in group B. Later hemodynamic differences between the groups are thereby attributed to a detrimental impact of high-dose epinephrine on the heart during resuscitation.
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J. Cardiothorac. Vasc. Anesth. · Apr 1993
Comparative StudyPercutaneous pericardiocentesis versus subxiphoid pericardiotomy in cardiac tamponade due to postoperative pericardial effusion.
In a retrospective study, 42 patients with acute cardiac tamponade due to pericardial effusion were evaluated following cardiac surgery, and the pericardial fluid was drained by one of two alternative methods: two-dimensional echocardiographic-guided pericardiocentesis (2D-echo) or subxiphoid surgical pericardiotomy. During the first period (from 1982 to 1986), one of the two methods was chosen by the treating physicians, whereas in the second period (from 1986 to 1991), 2D-echo-guided pericardiocentesis was the treatment of choice. Percutaneous pericardiocentesis was performed using local anesthesia in 29 patients. ⋯ Sixteen patients who underwent surgical pericardiotomy had complete evacuation of pericardial fluid without major complications (two of them suffered atrial arrhythmias during the procedure). The average amount of fluid drained, as well as the localization of the effusions, were the same for both groups. 2D-echo-guided pericardiocentesis was found to be a useful, safe, and simple technique. It can be used as an alternative treatment to subxiphoid pericardiotomy for cardiac tamponade due to postoperative pericardial effusions.