3 research outputs found
Partial liquid ventilation improves lung function in ventilation-induced lung injury
Disturbances in lung function and lung mechanics are present after
ventilation with high peak inspiratory pressures (PIP) and low levels of
positive end-expiratory pressure (PEEP). Therefore, the authors
investigated whether partial liquid ventilation can re-establish lung
function after ventilation-induced lung injury. Adult rats were exposed to
high PIP without PEEP for 20 min. Thereafter, the animals were randomly
divided into five groups. The first group was killed immediately after
randomization and used as an untreated control. The second group received
only sham treatment and ventilation, and three groups received treatment
with perfluorocarbon (10 mL x kg(-1), 20 mL x kg(-1), and 20 ml x kg(-1)
plus an additional 5 mL x kg(-1) after 1 h). The four groups were
maintained on mechanical ventilation for a further 2-h observation period.
Blood gases, lung mechanics, total protein concentration, minimal surface
tension, and small/large surfactant aggregates ratio were determined. The
results show that in ventilation-induced lung injury, partial liquid
ventilation with different amounts of perflubron improves gas exchange and
pulmonary function, when compared to a group of animals treated with
standard respiratory care. These effects have been observed despite the
presence of a high intra-alveolar protein concentration, especially in
those groups treated with 10 and 20 mL of perflubron. The data suggest
that replacement of perfluorocarbon, lost over time, is crucial to
maintain the constant effects of partial liquid ventilation
Comparison of exogenous surfactant therapy, mechanical ventilation with high end-expiratory pressure and partial liquid ventilation in a model of acute lung injury
We have compared three treatment strategies, that aim to prevent
repetitive alveolar collapse, for their effect on gas exchange, lung
mechanics, lung injury, protein transfer into the alveoli and surfactant
system, in a model of acute lung injury. In adult rats, the lungs were
ventilated mechanically with 100% oxygen and a PEEP of 6 cm H2O, and acute
lung injury was induced by repeated lung lavage to obtain a PaO2 value <
13 kPa. Animals were then allocated randomly (n = 12 in each group) to
receive exogenous surfactant therapy, ventilation with high PEEP (18 cm
H2O), partial liquid ventilation or ventilation with low PEEP (8 cm H2O)
(ventilated controls). Blood-gas values were measured hourly. At the end
of the 4-h study, in six animals per group, pressure-volume curves were
constructed and bronchoalveolar lavage (BAL) was performed, whereas in the
remaining animals lung injury was assessed. In the ventilated control
group, arterial oxygenation did not improve and protein concentration of
BAL and conversion of active to non-active surfactant components increased
significantly. In the three treatment groups, PaO2 increased rapidly to >
50 kPa and remained stable over the next 4 h. The protein concentration of
BAL fluid increased significantly only in the partial liquid ventilation
group. Conversion of active to non-active surfactant components increased
significantly in the partial liquid ventilation group and in the group
venti