Critical care medicine
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Critical care medicine · Dec 1989
Randomized Controlled Trial Clinical TrialSuccinylcholine and atropine for premedication of the newborn infant before nasotracheal intubation: a randomized, controlled trial.
Twenty preterm newborn infants were randomized to receive either atropine alone (20 micrograms/kg) or atropine plus succinylcholine (2 mg/kg) before nasotracheal intubation. Heart rate, BP, transcutaneous PO2, and intracranial pressure were monitored continuously before, during, and after intubation. No infants developed bradycardia or hypoxia. ⋯ BP increased during intubation in both groups, and the overall peak BP was not significantly different between the groups. Intubation was significantly shorter in the infants receiving succinylcholine. Premedication with succinylcholine and atropine will facilitate intubation of neonates, and ameliorate the adverse physiologic consequences of this procedure.
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Critical care medicine · Dec 1989
Comparative StudyEpinephrine versus methoxamine in survival postventricular fibrillation and cardiopulmonary resuscitation in dogs.
Previous studies have indicated that methoxamine (an alpha adrenergic receptor agonist) may provide an advantage compared to epinephrine (a mixed alpha and beta adrenergic agonist) during cardiac arrest and CPR. To test this theory, we compared the effects of bolus injections of epinephrine vs. methoxamine on survival, hemodynamic variables, blood gases, and blood lactate concentrations during ventricular fibrillation and CPR in 12 dogs. Each dog underwent a 3-min fibrillatory arrest followed by 10 min of fibrillation and CPR, at which time the animals were defibrillated. ⋯ Both epinephrine and methoxamine produced identical survival rates (5/6) with no differences in coronary perfusion pressure gradients or blood gases (aortic, venous, or great cardiac venous pH, PaO2, or PaCO2) during CPR. Also, there were no differences between the two study groups in myocardial lactate or oxygen extraction ratios during CPR. We conclude that in the dosages tested in our experimental model, epinephrine and methoxamine produce similar results in the variables which we measured.
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Critical care medicine · Dec 1989
Comparative StudyBrain pH effects of NaHCO3 and Carbicarb in lactic acidosis.
The effects of iv sodium bicarbonate (NaHCO3) and Carbicarb, an experimental buffer, were compared in a rat model of lactic acidosis induced by controlled hemorrhage and asphyxia. Although both NaHCO3 and Carbicarb were effective at alkalinizing the arterial blood in this model, NaHCO3 administration resulted in a rise in PaCO2 where Carbicarb did not (+9 +/- 2 vs. +2 +/- 2 torr at 2 min after infusion, p less than .01). Moreover, NaHCO3 resulted in a small decrease in intracellular brain pH as measured with P-31 nuclear magnetic resonance where Carbicarb afforded intracellular brain alkalinization (-0.03 +/- 0.01 vs. +0.08 +/- 0.02 pH units at 2 min, p less than .01). If these data are confirmed clinically, Carbicarb may offer advantages over NaHCO3 under conditions of fixed or limited ventilation.
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Critical care medicine · Dec 1989
Bronchocutaneous fistula in dogs: influence of fistula size and ventilatory mode on airleak.
Bronchocutaneous fistula (BCF) can originate at different levels, from the major airways to the peripheral lung. Little is published on the influence of the fistula origin or the ventilatory effect of the airleak. This study evaluates relative CO2 elimination via fistulas of various size and how different ventilatory modes influence both the quantity and quality, i.e., oxygen and CO2 content, of the airleak. ⋯ PfCO2 was not significantly influenced by the tube size and Vf. Fistula air alveolization was increased only with HF ventilation. Air leaked via the fistula contributed significantly to gas exchange; even when expiration was totally via the fistula, the arterial gases remained unchanged.(ABSTRACT TRUNCATED AT 250 WORDS)
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Critical care medicine · Dec 1989
ReviewInformed consent in theory and practice: legal and medical perspectives on the informed consent doctrine and a proposed reconceptualization.
The theoretical, legal, and medical doctrines of informed consent are analyzed. The elements of informed consent include disclosure of information, competency, understanding, voluntariness, and decision-making. The doctrine is ground in deference to individual autonomy and recognition that the exercise of self-determination in matters of health is a liberty interest honored by our history and traditions. ⋯ Medical decision-making is a complex, evolving pursuit of a diagnosis and proper treatment regimen. Moreover, patients are not always interested in the role assigned to them by law. A reconceptualization of informed consent doctrines utilizing sliding scale standards based on variables pertinent to each individual patient is suggested.