Objective To compare the effects of high frequency oscillatory ventilation (HFOV) and conventional mechanical ventilation (CMV) whith or without pulmonary surfactant(PS) supplement on water vapour inhalation injury.Methods New Zealand rabbits model of severe acute lung injury with acute respiratory failure caused by steam inhalation was established.Then the animals were treated by CMV，HFOV，CMV+PS or HFOV+PS，respectively while animals in control group did not ventilated and supplemented with PS.Femoral arterial blood samples were obtained at 1，2，3，4 h after treatment for blood gas analysis.4 h after treatment ,the lowest lobe of right lung was weighed for calculating wet-to-dry weight ratio (W/D).Four different parts including dependent areas and non-dependent areas of the middle lobe of right lung were excised for histological observation.Results (A) After ALI established PaO2 in the five groups decreased below 60mmHg (Plt;0.01) but intergroup differences were found.Meanwhile the change of PaCO2 showd no statistical significance(Pgt;0.05).(B) PaO2 in the four treatment groups had increased since one hour after treatmentand sustained at favorite levels during treatment period.PaO2 in the HFOV and HFOV+PS groups were higher than those in CMV and CMV+PS groups,respectively (Plt;0.01，Plt;0.05).PaO2 in the CMV+PS group at 2 h and HFOV+PS group at 2 h and 3 h were significantly higher than those in corresponding non-PS groups at the same timepoints (Plt;0.05).P（A-a）O2 in the HFOV and HFOV+PS groups were lower than those in CMV and CMV+PS groups (Plt;0.05).P（A-a）O2 in the two groups with PS at 2 h，3 h and 4 h t were statistically lower than those in the two corresponding groups without PS (Plt;0.05).The pH and PaCO2 as well as circulatory function in the four groups were not significantly different at different treatment timepoints (Pgt;0.05).(C) Lung W/D was not different between CMV and HFOV groups (Pgt;0.05)，or CMV+PS and HFOV+PS.But lung W/D in the two groups treated with PS showed statistically decrement than that in non-PS groups (Plt;0.05).(D) Histological injury score was lowest in HFOV+PS group and highest in CMV group.Conclusion HFOV combined with exogenous PS supplement can improve arterial oxygenation and alleviate pulmonary edema and injury，which may be a optimal method for the treatment of acute lung injury with acute respiratory failure caused by water vapour inhalation.
ObjectiveTo retrospectively compare the clinical effects of high frequency oscillatory ventilation (HFOV) and conventional ventilation (CV) on patients with acute respiratory distress syndrome (ARDS) induced by smoke inhalation injury. MethodsForty-three patients with smoke inhalation induced ARDS were admitted in the Center Hospital of Hu Ludao between October 2004 and June 2015.Among the patients, 19 cases were treated with CV (CV group) and 24 cases were treated with HFOV (HFOV group).The clinical data were collected and compared between two groups including blood gas at certain time points (6 h, 24 h, 48 h, 96 h, and 7 d) as well as complications and prognosis. ResultsThere was no significant difference in arterial blood gas between two groups before treatment (P > 0.05).After ventilation treatment, there were significant differences in arterial blood gas parameters between two groups except arterial carbon dioxide partial pressure at 48 and 96 h.And the patients in the HFOV group improved more obviously.The hospitalization time and ventilation time in the HFOV group were significantly shorter than those in the CV group (P < 0.05).No significant difference was found between two groups in the incidences of mortality, complications or 30-day survival rate (P > 0.05). ConclusionsBoth high frequency oscillatory ventilation and conventional ventilation can improve the clinical status in patients with smoke inhalation induced ARDS.These two ventilation modes do not present any difference with respect to prognosis by present evidence.