In:
Critical Care Medicine, Ovid Technologies (Wolters Kluwer Health), Vol. 39, No. 10 ( 2011-10), p. 2314-2321
Abstract:
The role of airway pressure release ventilation in the management of early smoke inhalation injury has not been studied. We compared the effects of airway pressure release ventilation and conventional mechanical ventilation on oxygenation in a porcine model of acute respiratory distress syndrome induced by wood smoke inhalation. Design: Prospective animal study. Setting: Government laboratory animal intensive care unit. Patients: Thirty-three Yorkshire pigs. Interventions: Smoke inhalation injury. Measurements and Main Results: Anesthetized female Yorkshire pigs (n = 33) inhaled room-temperature pine-bark smoke. Before injury, the pigs were randomized to receive conventional mechanical ventilation (n = 15) or airway pressure release ventilation (n = 12) for 48 hrs after smoke inhalation. As acute respiratory distress syndrome developed (PaO 2 /Fio 2 ratio 〈 200), plateau pressures were limited to 〈 35 cm H 2 O. Six uninjured pigs received conventional mechanical ventilation for 48 hrs and served as time controls. Changes in PaO 2 /Fio 2 ratio, tidal volume, respiratory rate, mean airway pressure, plateau pressure, and hemodynamic variables were recorded. Survival was assessed using Kaplan-Meier analysis. PaO 2 /Fio 2 ratio was lower in airway pressure release ventilation vs. conventional mechanical ventilation pigs at 12, 18, and 24 hrs ( p 〈 .05) but not at 48 hrs. Tidal volumes were lower in conventional mechanical ventilation animals between 30 and 48 hrs post injury ( p 〈 .05). Respiratory rates were lower in airway pressure release ventilation at 24, 42, and 48 hrs ( p 〈 .05). Mean airway pressures were higher in airway pressure release ventilation animals between 6 and 48 hrs ( p 〈 .05). There was no difference in plateau pressures, hemodynamic variables, or survival between conventional mechanical ventilation and airway pressure release ventilation pigs. Conclusions: In this model of acute respiratory distress syndrome caused by severe smoke inhalation in swine, airway pressure release ventilation-treated animals developed acute respiratory distress syndrome faster than conventional mechanical ventilation-treated animals, showing a lower PaO 2 /Fio 2 ratio at 12, 18, and 24 hrs after injury. At other time points, PaO 2 /Fio 2 ratio was not different between conventional mechanical ventilation and airway pressure release ventilation.
Type of Medium:
Online Resource
ISSN:
0090-3493
DOI:
10.1097/CCM.0b013e318225b5b3
Language:
English
Publisher:
Ovid Technologies (Wolters Kluwer Health)
Publication Date:
2011
detail.hit.zdb_id:
2034247-0
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