Assisted ventilation modes reduce the expression of lung inflammatory and fibrogenic mediators in a model of mild acute lung injury.
Intensive Care Med
; 36(8): 1417-26, 2010 Aug.
Article
en En
| MEDLINE
| ID: mdl-20333356
ABSTRACT
PURPOSE:
The goal of the study was to compare the effects of different assisted ventilation modes with pressure controlled ventilation (PCV) on lung histology, arterial blood gases, inflammatory and fibrogenic mediators in experimental acute lung injury (ALI).METHODS:
Paraquat-induced ALI rats were studied. At 24 h, animals were anaesthetised and further randomized as follows (n = 6/group) (1) pressure controlled ventilation mode (PCV) with tidal volume (V (T)) = 6 ml/kg and inspiratory to expiratory ratio (IE) = 12; (2) three assisted ventilation modes (a) assist-pressure controlled ventilation (APCV12) with IE = 12, (b) APCV11 with IE = 11; and (c) biphasic positive airway pressure and pressure support ventilation (BiVent + PSV), and (3) spontaneous breathing without PEEP in air. PCV, APCV11, and APCV12 were set with P (insp) = 10 cmH(2)O and PEEP = 5 cmH(2)O. BiVent + PSV was set with two levels of CPAP [inspiratory pressure (P (High) = 10 cmH(2)O) and positive end-expiratory pressure (P (Low) = 5 cmH(2)O)] and inspiratory/expiratory times T (High) = 0.3 s and T (Low) = 0.3 s. PSV was set as follows 2 cmH(2)O above P (High) and 7 cmH(2)O above P (Low). All rats were mechanically ventilated in air and PEEP = 5 cmH(2)O for 1 h.RESULTS:
Assisted ventilation modes led to better functional improvement and less lung injury compared to PCV. APCV11 and BiVent + PSV presented similar oxygenation levels, which were higher than in APCV12. Bivent + PSV led to less alveolar epithelium injury and lower expression of tumour necrosis factor-alpha, interleukin-6, and type III procollagen.CONCLUSIONS:
In this experimental ALI model, assisted ventilation modes presented greater beneficial effects on respiratory function and a reduction in lung injury compared to PCV. Among assisted ventilation modes, Bi-Vent + PSV demonstrated better functional results with less lung damage and expression of inflammatory mediators.
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Fibrosis Pulmonar
/
Respiración Artificial
/
Neumonía Asociada al Ventilador
/
Lesión Pulmonar Aguda
Tipo de estudio:
Prognostic_studies
Límite:
Animals
Idioma:
En
Revista:
Intensive Care Med
Año:
2010
Tipo del documento:
Article
País de afiliación:
Brasil