High-frequency oscillatory ventilation combined with partial liquid ventilation in experimental lung injury: effects on lung cell apoptosis

Summary Objective To investigate the effects of high-frequency oscillatory ventilation (HFOV) and partial liquid ventilation (PLV) on apoptosis of lung tissue induced by steam inhalation injury in rabbit. Design A prospective, randomized, controlled, multiple-group study. Setting An animal research laboratory centre in a university burns centre. Subjects New Zealand rabbits ( n = 32; 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 inspiratory:expiratory ratio of 1:1, and an FiO 2 of 1.0. After the induction of acute lung injury (ALI) by steam inhalation, the animals were randomly divided into four groups: CMV, HFOV, CMV + PLV, HFOV + PLV group. Then they were ventilated for 4 h by CMV, HFOV, CMV + PLV and HFOV + PLV, respectively. After the experimental period, cell apoptosis and apoptosis indexes in the lung tissue were assessed with TUNEL FragELTM (Fragment End Labeling). Results Lung tissue apoptosis indexes in HFOV group and HFOV + PLV group were lower than that of in CMV group and CMV + PLV group; between-group comparison had significant difference ( P