Critical care medicine
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To investigate the relationship between neurologic outcome and blood glucose concentrations in survivors of cardiopulmonary arrest. ⋯ The present study does not support an association between the concentration of glucose post-CPR and neurologic outcome. The previously reported casual relationship between hyperglycemia and neurologic prognosis may be an epiphenomenon of the severity of global cerebral ischemia in humans.
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Critical care medicine · May 1996
Evaluation of the effects of autotransfusion of unprocessed blood on hemodynamics and oxygen transport in anesthetized pigs.
To examine the hemodynamic effects and the oxygen transport pattern of autotransfusion of unprocessed blood on hemodynamics and oxygen transportation. ⋯ Reinfusion of large amounts of unprocessed blood (up to 40% of blood volume), collected with compresses from a noncontaminated surgical field is a cheap method, which may be of potential benefit in trauma patients, when more sophisticated autotransfusion devices are lacking. In the present study, this method resulted in transient but significant hemodynamic changes in the pulmonary circulation. Impairment of oxygen transport was noticed after the end of hemorrhage, but this impairment cannot be attributed to the autotransfusion technique alone, but also to factors such as hemorrhagic shock, surgical trauma, etc.
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Critical care medicine · May 1996
Randomized Controlled Trial Clinical TrialClosed-loop control of airway occlusion pressure at 0.1 second (P0.1) applied to pressure-support ventilation: algorithm and application in intubated patients.
Airway occlusion pressure at 0.1 sec (P0.1) is an index of respiratory center output. During pressure-support ventilation, P0.1 correlates with the mechanical output of the inspiratory muscles and has an inverse relationship with the amount of pressure-support ventilation. Based on these observations, we designed a closed-loop control which, by automatically adjusting pressure-support ventilation, stabilizes P0.1, and hence patient inspiratory activity, at a desired target. The purpose of the study was to demonstrate the feasibility of the method, rather than its efficacy or even its influence on patient outcome. ⋯ The study shows that P0.1 can be automatically controlled by pressure-support ventilation adjustments with a computer. Inspiratory activity can thus be stabilized at a level prescribed by the physician.
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Critical care medicine · May 1996
Comparative StudyNitric oxide synthase inhibition versus norepinephrine for the treatment of hyperdynamic sepsis in sheep.
To investigate the effects of Nomega-mono-methyl-L-arginine (L-NMMA), an inhibitor of nitric oxide synthesis, on hemodynamics, oxygen transport, and regional blood flow in an ovine model of hyperdynamic sepsis and to compare these effects with the responses to norepinephrine. ⋯ Blocking nitric oxide synthase had a marked vasoconstrictive effect. Both norepinephrine and L-NMMA increased arterial pressure without reducing renal blood flow, leading to an improved renal function.
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Critical care medicine · May 1996
Effect of human hemoglobin on systemic and regional hemodynamics in a porcine model of endotoxemic shock.
Excessive release of nitric oxide has been implicated as being an important factor contributing to systemic arterial hypotension in septic shock. Hemoglobin is an effective nitric oxide scavenger. The purpose of this study was to test the hypothesis that treatment with cross-linked human hemoglobin can ameliorate systemic arterial hypotension and improve organ perfusion in a porcine model of normodynamic endotoxemic shock. ⋯ Treatment with hemoglobin improved mean arterial pressure in endotoxemic swine without significantly impairing blood flow to the renal or mesenteric vascular beds. Infusion of hemoglobin, however, significantly exacerbated endotoxin-induced pulmonary hypertension and arterial hypoxemia. Additional pharmacologic strategies may be necessary to ameliorate the potential adverse pulmonary effects of administering hemoglobin solutions to patients with sepsis.