High-frequency percussive ventilation attenuates lung injury in a rabbit model of gastric juice aspiration.
OBJECTIVE
To test the effects of high-frequency percussive ventilation (HFPV) compared with high-frequency oscillatory ventilation (HFOV) and low-volume conventional mechanical ventilation (LVCMV), on lung injury course in a gastric juice aspiration model.


METHODS
Prospective, randomized, controlled, in-vivo animal study.


METHODS
University animal research laboratory.


METHODS
Forty-three New Zealand rabbits.


METHODS
Lung injury was induced by intratracheal instillation of human gastric juice in order to achieve profound hypoxaemia (PaO2/FIO2< or =50). Animals were ventilated for 4h after randomization in one of the following four groups: HFPV (median pressure 15cmH2O); LVCMV (VT 6mlkg(-1) and PEEP set to reach 15cmH2O plateau pressure); HFOV (mean pressure 15cmH2O); and a high-volume control group HVCMV (VT 12ml kg(-1) and ZEEP).


RESULTS
Static respiratory compliance increased after the ventilation period in the HFPV, LVMCV and HFOV groups, in contrast with the HVCMV group. PaO2/FIO2 improved similarly in the HFPV, LVCMV and HFOV groups, and remained lower in the HVCMV group than in the three others. Lung oedema, myeloperoxidase and histological lung injury score were higher in the HVCMV group, but not different among all others. Arterial lactate markedly increased after 4h of ventilation in the HVCMV group, while lower but similar levels were observed in the three other groups.


CONCLUSIONS
HFPV, like HFOV and protective CMV, improves respiratory mechanics and oxygenation, and attenuates lung damage. The HFPV provides attractive lung protection, but further studies should confirm these results before introducing HFPV into the clinical arena.
Allardet-Servent
Jérôme
J
Service de Réanimation Médicale, Hôpital Sainte-Marguerite, 270 Boulevard Sainte-Marguerite, 13274 Marseille Cedex 9, France. jerome.allardet-servent@mail.ap-hm.fr
Bregeon
Fabienne
F
Delpierre
Stéphane
S
Steinberg
Jean-Guillaume
JG
Payan
Marie-José
MJ
Ravailhe
Sylvie
S
Papazian
Laurent
L
D000818:Animals; D005750:Gastric Juice; D006612:High-Frequency Ventilation / Q000009:adverse effects* / Q000379:methods; D023421:Models, Animal; D011015:Pneumonia, Aspiration; D011446:Prospective Studies; D011817:Rabbits; D011897:Random Allocation; D012128:Respiratory Distress Syndrome / Q000209:etiology* / Q000503:physiopathology; D015656:Respiratory Mechanics