Critical care medicine
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To describe the physiologic mechanisms of ventilator-induced lung injury and to define the major ventilator and host-dependent risk factors that contribute to such injury. ⋯ Ventilation with high tidal volumes can increase vascular filtration pressures; produce stress fractures of capillary endothelium, epithelium, and basement membrane; and cause lung rupture. Mechanical damage leads to leakage of fluid, protein, and blood into tissue and air spaces or leakage of air into tissue spaces. This process is followed by an inflammatory response and possibly a reduced defense against infection. Predisposing factors for lung injury are high peak inspiratory volumes and pressures, a high mean airway pressure, structural immaturity of lung and chest wall, surfactant insufficiency or inactivation, and preexisting lung disease. Damage can be minimized by preventing overdistention of functional lung units during therapeutic ventilation.
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Critical care medicine · Jan 1993
Comparative StudyAcute brain swelling after out-of-hospital cardiac arrest: pathogenesis and outcome.
First, to examine factors that may be related to brain swelling, which was identified by the absence or compression of the lateral and third ventricles and perimesencephalic cisterns on brain computed tomography (CT) scans in the early postresuscitation period in patients who suffered an out-of-hospital cardiac arrest. Second, to characterize the neurologic outcome in those patients in whom cardiac arrest was followed by brain swelling. ⋯ The cause of brain swelling may be related to the development of the metabolic acidosis (possibly lactic acidosis) due to hypoxia before the resuscitation period. Brain swelling may be one of the indicators that predicts a poor neurologic outcome in the patients who suffer an out-of-hospital cardiac arrest.
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Critical care medicine · Jan 1993
Synchronous mechanical ventilation of the neonate with respiratory disease.
To assess the importance of synchronization of mechanical ventilation with spontaneous respiratory efforts in mechanically ventilated neonates. The actions of this synchronization on ventilation, oxygenation, and BP variation were assessed. ⋯ Synchronous ventilation can be readily applied to most ventilated neonates. It improves ventilation, and results in a marked reduction in BP variation, which may have implications for reducing the risk of intraventricular hemorrhage.
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Critical care medicine · Jan 1993
Effects of dense, high-volume, artificial surfactant aerosol on a heated exhalation filter system.
To evaluate a supplemental heated filter system during mechanical ventilation with continuous nebulization of an artificial surfactant by a new, high-volume nebulizer. ⋯ The supplemental filter system was able to protect the ventilatory exhalation sensors for approximately 7 hrs at a minute ventilation of 20 L/min. Steam sterilization did not extend the supplemental filter life.
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Critical care medicine · Jan 1993
Respiratory mechanics and bronchodilator responsiveness in patients with the adult respiratory distress syndrome.
To study the effects of salbutamol (a selective beta 2-adrenergic receptor agonist) on respiratory mechanics in patients with the adult respiratory distress syndrome (ARDS). ⋯ In ARDS patients, salbutamol decreases the abnormally high airway resistance, by reducing minimum resistance, but has no effect on the effective additional resistance.