Effects of high-frequency oscillatory ventilation and partial liquid ventilation on acute lung injury induced by steam inhalation in new zealand rabbits.

OBJECTIVE

to investigate the beneficial effects of high-frequency oscillatory ventilation (HFOV) and partial liquid ventilation (PLV) in treating acute lung injury induced by steam inhalation.

DESIGN

a prospective, randomized, controlled, multiple group study.

SETTING

an animal research centre laboratory in a university burns centre.

SUBJECTS

New Zealand rabbits (n = 30; 2.25 ± 0.25 kg) of either sex.

INTERVENTIONS

the animals were ventilated by HFOV with a mean airway pressure of 10 cm H (2)O, a frequency of 10 Hz, an amplitude of 20 cm H (2)O, an I:E ratio of 1:1, and an FiO (2)of 1.0. After the induction of acute lung injury by steam inhalation, the animals were randomly assigned to receive either HFOV alone or a combined therapy of HFOV + PLV. The animals were grouped as HFOV, HFOV + PLV, and control group (without ventilation after recovery from muscular relaxation).

MEASUREMENTS AND MAIN RESULTS

arterial blood gases, cardiovascular haemodynamics, dynamic lung compliance, and total lung injury scores were measured. After steam inhalation, all three groups displayed low PaO (2)and low dynamic lung compliance. In the control group all the animals died within 3 h. In the HFOV and HFOV + PLV groups, all the animals displayed significant improvements in dynamic lung compliance, oxygenation, and histological outcomes; HFOV + PLV showed the best results.

CONCLUSION

in a New Zealand rabbit model of steam inhalation injury, HFOV improved oxygenation, increased dynamic lung compliance, and alleviated lung histological injury. Combined therapy with HFOV + PLV was clearly superior to that with HFOV alone during the observation period.