Critical care medicine
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Critical care medicine · Jan 1997
Influence of airway pressure on minimum occlusive endotracheal tube cuff pressure.
To examine the in vivo relationship between peak inflation pressure and the minimum occlusive pressure of a "high-volume, low-pressure" endotracheal tube cuff that may in some circumstances promote tracheal ischemic complications. ⋯ Knowledge of the linear relationship between peak inflation pressure and minimum occlusive pressure can help the clinician identify patients who may be at risk for cuff-induced tracheal ischemic complications, such as tracheoesophageal fistula and tracheal stenosis. In our series, a cuff pressure of 25 mm Hg corresponded to a peak inflation pressure of 35.3 mm Hg (48 cm H2O). Patients with higher peak inflation pressures may be at risk for ischemic tracheal injury, despite proper cuff inflation techniques.
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Critical care medicine · Jan 1997
Comparative StudyType B lactic acidosis following cardiopulmonary bypass.
To describe, characterize, and identify the associations of postcardiac surgical lactic acidosis occurring in the absence of clinical evidence of tissue hypoperfusion. ⋯ This report documents the occurrence of lactic acidosis in a subgroup of patients undergoing cardiopulmonary bypass. The pathogenesis of this disorder is uncertain, but it appears to not relate to inadequate oxygen delivery. Systemic vasodilation and reduced oxygen extraction appear to be features of this disorder, which has an excellent prognosis.
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Critical care medicine · Jan 1997
Comparative StudyNear-infrared spectroscopy: continuous measurement of cytochrome oxidation during hemorrhagic shock.
Mitochondrial cytochrome a,a3 redox shifts can be determined by near-infrared wavelength reflection. Since near-infrared wavelengths penetrate skin and bone, a potential exists to noninvasively measure mitochondrial oxidation using this phenomenon. The purpose of this study was to compare conventional parameters of resuscitation with regional measurements of spectroscopically derived cytochrome redox state in a hemorrhagic shock model. ⋯ Resuscitation from severe hemorrhagic shock may not uniformly restore cellular oxygenation, despite normalization of traditional parameters of resuscitation. Direct monitoring of cytochrome oxidation may be useful in identifying regional areas of dysoxia.
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Critical care medicine · Jan 1997
Comparative StudyEfficacy of inhaled nitric oxide in oleic acid-induced acute lung injury.
To assess the efficacy of inhaled nitric oxide in improving pulmonary hypertension and gas exchange following oleic acid-induced acute lung injury. ⋯ The effect of inhaled nitric oxide, restricted to relieving pulmonary vasoconstriction in this model of lung injury, may have limited benefit in improving pulmonary gas exchange when diffusion is impaired by severe lung injury and inflammatory thickening of the alveolar-capillary barrier. Nitric oxide inhalation may have better results when used at an earlier, less severe stage of acute lung injury.
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Critical care medicine · Jan 1997
Effect of continuous venovenous hemofiltration with dialysis on lactate clearance in critically ill patients.
To evaluate the effect of continuous venovenous hemofiltration with dialysis on lactate elimination by critically ill patients. ⋯ Continuous venovenous hemofiltration with dialysis cannot mask lactate overproduction, and its blood concentration remains a reliable marker of tissue oxygenation in patients receiving this renal replacement technique.