Critical care medicine
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Critical care medicine · Dec 1993
Prognostic and clinical relevance of pupillary responses, intracranial pressure monitoring, and brainstem auditory evoked potentials in comatose patients with acute supratentorial mass lesions.
To test the hypothesis that the clinical condition and outcome in patients with acute supratentorial mass lesions can be assessed by determination of pupillary abnormalities, measurement of intracranial pressure, and results of brainstem auditory evoked potentials. ⋯ Pupillary abnormalities may serve as a reliable parameter, which may even be superior to brainstem auditory evoked potential testing and intracranial pressure monitoring for prediction of outcome in comatose individuals with supratentorial mass lesions. Brainstem auditory evoked potentials can be used to support the clinical relevance of abnormal pupillary status and increased intracranial pressure but are of no prognostic value. Increased intracranial pressure is associated with abnormalities in pupillary status and brainstem auditory evoked potentials. Examination for pupillary abnormalities in combination with intracranial pressure monitoring and brainstem auditory evoked potential testing seems to be a useful strategy in managing patients with supratentorial mass lesions in critical care units.
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Critical care medicine · Dec 1993
Cardiac arrest presenting with rhythms other than ventricular fibrillation: contribution of resuscitative efforts toward total survivorship.
The medical literature portrays a bleak prognosis for out-of-hospital cardiac arrest cases presenting with asystole, idioventricular rhythms with pulselessness, or primary electromechanical dissociation. In view of evolving philosophies to waive resuscitation attempts in such cases, we sought to delineate the actual contribution toward overall survivorship that is provided by resuscitation efforts for patients who have these electrocardiographic presentations. ⋯ Despite poor survival "rates," resuscitative efforts for patients presenting with asystole, electromechanical dissociation, and idioventricular rhythms with pulselessness all contribute significantly toward a community's total survivorship from out-of-hospital cardiac arrest. Initial, aggressive attempts at resuscitation still should be emphasized in such patients.
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Gradual, almost imperceptible transitions occur between localized infection, generalized infection, systemic manifestations of the sepsis syndrome, septic shock, and death. The aim of this study was to describe the sequential pattern of hemodynamic and oxygen transport patterns of survivors and nonsurvivors of septic shock, so as to differentiate primary from secondary and tertiary events, to evaluate possible physiologic mechanisms, and to provide a template to relate the appearance of biochemical mediators to the sequence of physiologic events. ⋯ Increased cardiac index and DO2 represent compensations for circulatory deficiencies that limit body metabolism, as reflected by inadequate VO2. Survivors have higher cardiac index, DO2, and VO2 values than those values of both the nonsurvivors and normal values. These data suggest that therapy should be directed toward increasing cardiac index to > 5.5 L/min/m2, DO2 to > 1000 mL/min/m2, and VO2 to > 190 mL/min/m2 as therapeutic goals; these supranormal values were empirically determined by the patterns of the survivors. Further studies to describe temporal relationships of biochemical mediators of these physiologic patterns are needed.
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Critical care medicine · Dec 1993
Comparative StudyCardiorespiratory consequences of expiratory chest wall compression during mechanical ventilation and severe hyperinflation.
To measure and compare the effects of manual expiratory compression of either the rib cage or abdomen on cardiac output, end-expiratory lung volume, and other cardiorespiratory variables in an animal model that mimics the severe pulmonary hyperinflation and hemodynamic impairment occurring in patients with severe acute asthma during mechanical ventilation. ⋯ The cardiorespiratory effects of manually compressing the rib cage or abdomen during expiration in this animal study suggest that these techniques should be carefully evaluated in mechanically ventilated patients with severe acute asthma.
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Critical care medicine · Dec 1993
Comparative StudyMetabolic acidemia with hypoxia attenuates the hemodynamic responses to epinephrine during resuscitation in lambs.
To examine the effects of metabolic acidemia and hypoxia on the hemodynamic responses to epinephrine in an intact neonatal animal model. ⋯ During the physiologic conditions associated with neonatal resuscitation, that is, hypoxia with a compromised hemodynamic state, metabolic acidemia significantly attenuates the hemodynamic responses to resuscitation with epinephrine and oxygen. Correction of metabolic acidosis may be warranted in newborn resuscitation.