Combining lung-protective strategies in experimental acute lung injury: The impact of high-frequency partial liquid ventilation.
OBJECTIVE
To evaluate the independent and combined effects of high-frequency oscillatory ventilation (HFOV) and partial liquid ventilation (PLV) on gas exchange, pulmonary histopathology, inflammation, and oxidative tissue damage in an animal model of acute lung injury.


METHODS
Prospective, randomized animal study.


METHODS
Research laboratory of a health sciences university.


METHODS
Fifty New Zealand White rabbits.


METHODS
Juvenile rabbits injured by lipopolysaccharide infusion and saline lung lavage were assigned to conventional ventilation (CMV), PLV, HFOV, or high-frequency partial liquid ventilation (HF-PLV) with a full or half dose (HF-PLV1/2) of perfluorochemical (PFC). Uninjured ventilated animals served as controls. Arterial blood gases were obtained every 30 mins during the 4-hr study. Histopathologic evaluation was performed using a lung injury scoring system. Oxidative lung injury was assessed by measuring malondialdehyde and 4-hydroxynonenal in lung homogenates.


RESULTS
HFOV, PLV, or a combination of both methods (HF-PLV) resulted in significantly improved oxygenation, more favorable lung histopathology, reduced neutrophil infiltration, and attenuated oxidative damage compared with CMV. HF-PLV with a full PFC dose did not provide any additional benefit compared with HFOV alone. HF-PLV1/2 was associated with decreased pulmonary leukostasis compared with HF-PLV.


CONCLUSIONS
The combination of HFOV and PLV (HF-PLV) does not provide any additional benefit compared with HFOV or PLV alone in a combined model of lung injury when lung recruitment and volume optimization can be achieved. The use of a lower PFC dose (HF-PLV1/2) is associated with decreased pulmonary leukostasis compared with HF-PLV and deserves further study.
Rotta
Alexandre T
AT
Department of Anesthesiology, University of Texas Medical Branch at Galveston, Pediatric Critical Care, Driscoll Children's Hospital, Corpus Christi, TX, USA.
Viana
Mário Eduardo G
ME
Wiryawan
Budi
B
Sargentelli
Guilherme A
GA
Dowhy
Mark S
MS
Zin
Walter A
WA
Fuhrman
Bradley P
BP
D000447:Aldehydes / Q000032:analysis; D000818:Animals; D001784:Blood Gas Analysis; D035641:Chest Wall Oscillation / Q000379:methods*; D004195:Disease Models, Animal; D008070:Lipopolysaccharides / Q000009:adverse effects; D021061:Liquid Ventilation / Q000379:methods*; D008168:Lung / Q000378:metabolism / Q000473:pathology; D008315:Malondialdehyde / Q000032:analysis; D011817:Rabbits; D012128:Respiratory Distress Syndrome / Q000209:etiology / Q000628:therapy*; D012965:Sodium Chloride / Q000009:adverse effects
D000447:Aldehydes; D008070:Lipopolysaccharides; D012965:Sodium Chloride; D008315:Malondialdehyde; C027576:4-hydroxy-2-nonenal