Critical care medicine
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Critical care medicine · Jun 1991
Management of hyponatremic seizures in children with hypertonic saline: a safe and effective strategy.
To study efficacy and safety of hypertonic saline administration in the management of hyponatremic seizures. ⋯ Treatment of hyponatremic seizures with routine anticonvulsants may be ineffective and is associated with a considerable incidence of apnea. A rapid increase in the serum sodium concentration by 3 to 5 mmol/L with the use of hypertonic saline is safe and efficacious in managing acute symptomatic hyponatremia.
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Critical care medicine · Jun 1991
Oxygen delivery-dependent oxygen consumption in acute respiratory failure.
To investigate whether oxygen consumption (VO2) is dependent on oxygen delivery (DO2) in adult respiratory distress syndrome (ARDS) and non-ARDS acute respiratory failure. ⋯ VO2 is dependent on DO2 over a wide range of DO2 values in acute respiratory failure. This dependency phenomenon is much stronger in ARDS than in respiratory failure due to other causes. Due to the abnormal dependency of VO2 on DO2, changes in the oxygenation status may not be reflected by changes in mixed venous oxygen saturation in ARDS.
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Critical care medicine · Jun 1991
Hypertonic saline dextran resuscitation during the initial phase of acute endotoxemia: effect on regional blood flow.
Small-volume resuscitation by means of bolus application of hypertonic saline solutions has been demonstrated to restore central hemodynamics and regional blood flow in severe hemorrhagic and traumatic shock. The aim of this study was to elucidate the potential of this new concept for treatment of profound hypovolemia and microcirculatory deterioration associated with sepsis and endotoxic shock. In a porcine model of acute hyperdynamic endotoxemia (elicited by continuous iv infusion of Salmonella abortus equi endotoxin for 3.5 hrs), small-volume resuscitation applying hypertonic-hyperoncotic solutions was analyzed for its effect on central hemodynamics, oxygen delivery (Do2), and regional blood flow. Fluid therapy was initiated when the pulmonary artery occlusion pressure (PAOP) tended to decrease (at 43 to 52 mins of endotoxemia), and consisted of 4 mL/kg bolus infusion of either 7.2% sodium chloride, 10% dextran, or 10% dextran in 7.2% sodium chloride; thereafter, PAOP was maintained by controlled infusion of 6% dextran-60. In a control group, 6% dextran-60 was given without preinjection of hypertonic-hyperoncotic solutions. ⋯ Small-volume resuscitation by means of hypertonic saline-dextran proved the most effective, and seems to be an attractive supportive therapy to prevent microcirculatory failure in sepsis and endotoxemia.
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Critical care medicine · May 1991
ReviewOxygen transport in adult respiratory distress syndrome and other acute circulatory problems: relationship of oxygen delivery and oxygen consumption.
To evaluate the evidence that oxygen consumption (VO2) is pathologically dependent on oxygen delivery (DO2). ⋯ Pathologic dependence of VO2 on DO2, especially the inability to increase tissue oxygen extraction, is present in most patients with ARDS and many other critically ill individuals. PVO2 and CVO2 are both unreliable indicators of cardiac output, DO2, or VO2.
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Critical care medicine · May 1991
Comparative StudyOxygen transport measurements to evaluate tissue perfusion and titrate therapy: dobutamine and dopamine effects.
Increased cardiac index, oxygen delivery (DO2), and oxygen consumption (VO2) patterns were shown to characterize the physiologic status of surviving high-risk surgical patients, and indicate increased metabolic needs; relatively normal DO2 and VO2 values were found to characterize the sequential pattern of nonsurvivors who developed an early oxygen debt followed by lethal organ failure. The cardiac index, DO2, and VO2 values empirically determined from survivors' patterns were shown to improve outcome in prospective randomized trials. The present study considers these criteria to evaluate the tissue perfusion status as well as the effects of therapy on tissue perfusion and oxygenation. ⋯ The monitored patterns of cardiac index, DO2, and VO2 may be used to evaluate the adequacy of tissue perfusion as well as the relative effectiveness of alternative therapies. Second, these physiologic criteria may be used to titrate therapy in order to achieve optimal outcome. Third, after colloids optimally expand the plasma volume, dobutamine may be used to enhance flow and the distribution of flow in order to improve tissue oxygenation. Vasodilators may be used when hypertensive episodes occur or there is an inadequate response to inotropic agents. Vasopressors are used as a last resort, usually in the terminal or preterminal state.