Critical care medicine
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Critical care medicine · Aug 1996
Comparative StudyPositive end-expiratory pressure-induced hemodynamic changes are reflected in the arterial pressure waveform.
To examine whether the hemodynamic changes due to mechanical ventilation with positive end-expiratory pressure (PEEP) can be assessed by the respiratory-induced variations in the arterial pressure waveform during normovolemia and experimental acute ventricular failure. ⋯ Analysis of arterial pressure waveforms during mechanical ventilation reflected the decrease in cardiac output in dogs with normal cardiac function subjected to incremental PEEP. In dogs with acute ventricular failure in which PEEP did not affect cardiac output, the systolic pressure variation was similarly unaffected by PEEP. In the absence of cardiac output measurement during mechanical ventilation with PEEP, the analysis of the respiratory variations in the arterial pressure waveform may be useful in assessing changes in cardiac output.
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Critical care medicine · Aug 1996
Comparative StudyAlterations of myocardial and vascular adrenergic receptor-mediated responses in Escherichia coli-induced septic shock in the rat.
To investigate responsiveness to exogenous catecholamines in rat bacteremic shock by studying both myocardial and vascular functional parameters; to determine in the same study the relationship of these parameters with other relevant biological parameters of the adrenergic pathway, such as myocardial beta-adrenergic receptors and cyclic adenosine monophosphate (cAMP); and to indirectly approach the roles of tumor necrosis factor-alpha (TNF-alpha) and nitric oxide. ⋯ In ex vivo experiments, 3 hrs after E. coli injection, vascular responsiveness was sharply decreased. This impaired response was improved by inhibition of nitric oxide. The heart, nevertheless, was still able to modulate its inotropic and chronotropic response to isoproterenol, even though an impaired beta-adrenergic-receptor stimulation of cAMP was already present.
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Critical care medicine · Aug 1996
Hormonal and hemodynamic changes in a validated animal model of brain death.
To examine the hormonal and hemodynamic changes in a validated animal model of brain death. ⋯ In a validated animal model of brain death, significant decreases in the circulating concentrations of stress hormones, as well as hemodynamic instability, occurred after brain death. Measurements of plasma adrenocorticotrophic hormone and vasopressin values may be useful as diagnostic predictors of brain death. Furthermore, the observed changes may contribute to organ dysfunction after brain death and may necessitate hormonal as well as inotropic and vasoactive support to maintain donor organ function in the clinical setting.
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Critical care medicine · Jul 1996
Cost accounting of adult intensive care: methods and human and capital inputs.
To cost adult intensive care by determining inputs to production, resource consumption per patient, and total cost per intensive care unit (ICU) stay. ⋯ In order to develop strategies aimed at cost containment, it is first necessary to undertake a thorough examination of cost drivers. This detailed cost-accounting study determined inputs to production, resources consumed by individual patients, and costs incurred during ICU stay.
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Critical care medicine · Jul 1996
Randomized Controlled Trial Comparative Study Clinical TrialMicrobial contamination of blood conservation devices during routine use in the critical care setting: results of a prospective, randomized trial.
To compare microbial contamination of two different blood conservation devices; to determine if there was an association between contamination of the blood conservation devices and clinical infections; to determine if there was a significant user preference for either of the two devices. ⋯ The levels of microbial contamination noted in these devices were not consistent with clinical infection (defined as 10(3) cfu/mL on quantitative cultures). There was no significant difference in degree or pattern of contamination between the two devices. When utilized and changed according to the Centers for Disease Control guidelines, blood conservation devices are not harbors of infection in the critical care setting. Blood conservation devices can be used as part of a comprehensive blood conservation program in the critical care setting without undue concern for exacerbating infectious processes.