Critical care medicine
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Critical care medicine · Jan 1997
Variability of indices of hypoxemia in adult respiratory distress syndrome.
To determine the usefulness of indices of hypoxemia in assessing patients with the adult respiratory distress syndrome (ARDS). ⋯ All indices of hypoxemia are affected by changes in FIO2 in patients with ARDS. PaO2/FIO2 ratio exhibits the most stability at FIO2 values of > or = 0.5 and PaO2 values of < or = 100 torr (< or = 13.3 kPa), and is a useful estimation of the degree of gas exchange abnormality under usual clinical conditions. Venous admixture varies substantially with alteration of FIO2 in patients who have clinically important ventilation/perfusion abnormalities. Under these circumstances, venous admixture is a poor indicator of the efficiency of pulmonary oxygen exchange, even if venous admixture is calculated from measured arterial and venous oxygen content values. Estimated venous admixture, based on an assumed arterial-venous oxygen content difference, is even more unreliable.
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Critical care medicine · Jan 1997
Comparative StudyInfluence of prone position on the extent and distribution of lung injury in a high tidal volume oleic acid model of acute respiratory distress syndrome.
To evaluate the influence of body position on the extent and distribution of experimental lung damage in an oleic acid canine model of acute respiratory distress syndrome, using mechanical ventilation with high tidal volumes and positive end-expiratory pressure (PEEP). ⋯ After oleic acid-induced lung injury, animals ventilated with high tidal volume and PEEP undergo less extensive histologic change in the prone position than in the supine position. The prone position alters the distribution of histologic abnormalities.
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Critical care medicine · Jan 1997
Quality of life after cardiac surgery complicated by multiple organ failure.
To evaluate quality of life after prolonged multiple system intensive care treatment in cardiac surgical patients. ⋯ Patients treated with prolonged multiple system intensive care after heart surgery have a poor outcome with respect to quality of life measured at least 1 yr after discharge from the ICU.
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Critical care medicine · Jan 1997
Tracheal gas insufflation during pressure-control ventilation: effect of using a pressure relief valve.
Pressure-control ventilation minimizes alveolar overdistention by limiting peak airway pressure, but a consequence of this pressure limitation may be a reduction in tidal volume with subsequent hypercarbia. Tracheal gas insufflation (TGI) can be used in combination with pressure-control ventilation to augment CO2 elimination. During pressure-control ventilation with continuous TGI, we observed that peak airway pressure increased above the set inspiratory pressure. Based on this observation, we investigated the ability of the pressure-control ventilator circuit to compensate for continuous TGI and the effect of insertion of a pressure relief valve to eliminate over-pressurization. ⋯ A pressure relief valve is a necessary adjunct to maintain peak airway pressure at set inspiratory pressure and keep total inspiratory tidal volume constant when continuous TGI is administered in conjunction with pressure-control ventilation.
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Critical care medicine · Jan 1997
Comparative StudyThe yeast to hyphal transition following hematogenous candidiasis induces shock and organ injury independent of circulating tumor necrosis factor-alpha.
Dimorphic Candida albicans spp. increasingly cause lethal septic shock and disseminated infection in the critically ill. Following candidemia, production of specific fungal exotoxins coincident with the yeast to hyphal phenotypic transition is believed to be important in the pathogenesis of Candida septic shock. However, overexpression of the pleiotropic cytokine tumor necrosis factor (TNF)-alpha by the host following hyphal germination is also thought to be a mechanism of Candida-related cardiopulmonary dysfunction, as well as of bacteremic shock. In this study, we hypothesized that increases in circulating TNF-alpha coinciding with the yeast to hyphal transition modulate the onset and progression of shock with multiple organ injury early after hematogenous candidiasis. ⋯ Lethal C. albicans sepsis with lung injury and multiple organ damage are temporally associated with the in vivo yeast to hyphal transition in this model. However, this candidemic septic shock syndrome is modulated by circulating fungal virulence factors or host mediators other than TNF-alpha, a cytokine considered essen