The American review of respiratory disease
-
Am. Rev. Respir. Dis. · Jan 1989
Case ReportsAcute eosinophilic pneumonia: a hypersensitivity phenomenon?
A previously healthy young man presented with acute respiratory distress and diffuse bilateral infiltrates on chest radiograph. Eosinophilic pneumonia was diagnosed by bronchoalveolar lavage and confirmed by transbronchial lung biopsy. ⋯ The case presented here was acute in onset, suggesting a hypersensitivity reaction. High levels of bronchoalveolar lavage eosinophils indicate the diagnosis but not the etiology of eosinophilic pneumonia.
-
Am. Rev. Respir. Dis. · Dec 1988
Severe acute respiratory failure managed with continuous positive airway pressure and partial extracorporeal carbon dioxide removal by an artificial membrane lung. A controlled, randomized animal study.
Using an animal model of acute respiratory failure (ARF), we evaluated two treatments: conventional mechanical pulmonary ventilation (MV) and continuous positive airway pressure (CPAP) with extracorporeal removal of CO2 by an artificial membrane lung. We developed a model of "mild" ARF and a model of "severe" ARF after ventilating healthy sheep at a peak inspiratory pressure of 50 cm H2O for various lengths of time. Sheep from either injury models were randomly assigned to one of the above treatment groups. ⋯ Of 11 sheep from the model with "mild" ARF treated by MV, only three survived, whereas all 11 sheep from the model with "mild" ARF treated with CPAP and extracorporeal removal of CO2 responded well, and nine sheep ultimately recovered. We conclude that CPAP with extracorporeal removal of CO2 provided a better environment for the recovery in our model with "mild" ARF than the conventional arrangement centered on MV alone. Our studies also suggest that lung injury can progress (i.e., model with "severe" ARF) to where neither of the two treatments can succeed.
-
Am. Rev. Respir. Dis. · Nov 1988
External work output and force generation during synchronized intermittent mechanical ventilation. Effect of machine assistance on breathing effort.
We measured the mechanical work performed by 12 acutely ill patients during synchronized intermittent mandatory ventilation to determine the influence of volume-cycled machine assistance on inspiratory timing, respiratory muscle force development, and external work output. The frequency and tidal volume of spontaneous breaths increased at lower levels of mechanical ventilation, but inspiratory time fraction did not vary across the spectrum of machine support. As machine support was withdrawn, inspiratory work and pressure-time product increased progressively for both spontaneous and assisted breathing cycles. ⋯ We conclude that under the conditions of this study the ventilatory pump continued to be active at all levels of machine assistance. Although work per liter related linearly to the proportion of minute ventilation borne by the patient, force generation differed little for spontaneous and machine-aided breaths at any specified level of support. Whether judged on the basis of mean developed pressure (work per liter of ventilation) or pressure-time product, little effort adaptation to volume-cycled machine assistance appears to occur on a breath-by-breath basis.