Articles: respiratory-distress-syndrome.
-
Critical care medicine · Nov 1997
Comparative StudyEffects of inhaled nitric oxide and extracorporeal membrane oxygenation on pulmonary hemodynamics and lymph flow in oleic acid lung injury in sheep.
To compare the effects of inhaled nitric oxide (NO) and extracorporeal membrane oxygenation (ECMO) on oxygenation, hemodynamics, and lymphatic drainage in an oleic acid lung injury model in sheep. ⋯ In an oleic acid-induced sheep model of acute lung injury, there were significant differences between the effects of NO and ECMO on acute pulmonary hypertension, hypoxemia, hypercarbia, and lymph flow. NO significantly decreases pulmonary hypertension, whereas pulmonary hemodynamics were not substantially affected by ECMO. Both interventions reversed hypoxemia, but ECMO did so to a greater degree, and only ECMO improved hypercarbia. Only NO decreased lymph flow, possibly as an effect of decreased microvascular filtration pressure. This study did not attempt to evaluate the impact of these interventions on ventilatory requirements, barotrauma, or outcome. However, this model suggests that NO therapy may moderate pulmonary hypertension and improve lymph flow in acute lung injury. Clinical studies are needed to assess whether NO therapy might be beneficial in treatment of severe acute lung injury in older children and adults.
-
Comparative Study
The 67gallium-transferrin pulmonary leak index in pneumonia and associated adult respiratory distress syndrome.
1. The aim of the study was to determine the role of increased microvascular protein permeability, as measured by the 67gallium (Ga)-transferrin pulmonary leak index, in pneumonia and associated adult respiratory distress syndrome (ARDS). 2. Eighteen consecutive patients with microbiologically confirmed pneumonia (radiographic infiltrates, purulent sputum) and needing respiratory monitoring (n = 2) or mechanical ventilation (n = 16) in the intensive care unit were studied prospectively. ⋯ The 67Ga-transferrin pulmonary leak index parallels the degree of radiographic, ventilatory and lung mechanical abnormalities of pneumonia and evolving ARDS. The data support the idea that the clinical manifestations of pneumonia culminating in ARDS directly relate to the degree of microvascular injury. Conversely, the pulmonary leak index may be used to monitor the effect of anti-inflammatory drugs in the adjunctive treatment for severe pneumonia aimed at circumventing mechanical ventilation in future studies.
-
Critical care medicine · Nov 1997
Comparative StudyProlonged partial liquid ventilation using conventional and high-frequency ventilatory techniques: gas exchange and lung pathology in an animal model of respiratory distress syndrome.
To evaluate the effect of prolonged partial liquid ventilation with perflubron (partial liquid ventilation), using conventional and high-frequency ventilatory techniques, on gas exchange, hemodynamics, and lung pathology in an animal model of lung injury. ⋯ In this animal model, partial liquid ventilation using conventional or high-frequency ventilation provided rapid and sustained improvements in oxygenation without adverse hemodynamic consequences. Animals treated with partial liquid ventilation-flow interruption had a significantly decreased survival rate vs. animals treated with the other studied techniques. Histopathologic and morphometric analysis showed significantly less injury in the lower lobes of lungs from animals treated with partial liquid ventilation. High-frequency ventilation techniques did not further improve pathologic outcome.
-
We have measured the change of lung mechanical parameters on isolated rabbit lungs exposed to chlorine gas (Cl2). Experimental results show parallel increase in elastance and resistance of impaired lungs. We tried to determine whether this may be explained by a reduction of the ventilated areas in the lung, consecutive to closure of some airways. ⋯ With the symmetrical model, simulated results are comparable to experimental ones when the occlusion level is proximal. Whatever the dissymmetry level (delta) of the fractal tree model, we could not simulate the expected increase in resistance with the observed increase in elastance. We conclude that either the occlusion in non homogeneous or the lung impairment is not only a reduction in ventilated areas.