Effects Of Helium-oxygen Mechanical Ventilation On Respiratory Mechanics And Oxygenation In ALI Animal Models

Objective To investigate the effect of Helium-oxygen mechanical ventilation on respiratory mechanics and oxygenation in ARDS animal models. Methods To investigate the changes of respiratory mechanics and oxygenated indexs in acute lung injury rat models caused by sepsis in different end-expiratory positive pressure by comparing air-oxygen mixture mechanical ventilation with helium-oxygen mixture mechanical ventilation。And then to calculate lung tissue and observe the distinction of lung histomorphology. Results 1.Helium-oxygen mechanical ventilation cannot improve respiratory mechanical indexs in ARDS animal models(tidal volume,airway peak voltage,mean airway pressure,platform pressure,dynamic compliance,airway resistance,flow rate of peak value,dead space volume).on the contrary,in the condition of high level of peep,some indexs become worse, such as depress of dynamic compliance,the raise of airway resistance(P<0.05).2. Helium-oxygen mechanical ventilation unable to improve the oxygenation of organization in the same level of peep.3.Helium-oxygen mechanical ventilation has no influence on the change of lung histomorphology.Conclusion Helium-oxygen mixture mechanical ventilation has no influence on respiratory mechanics,oxygenated indexs and histomorphology in acute lung injury animal models,has not therapeutical effect of acute lung injury animas,in the contrary,helium-oxygen mixture mechanical ventilation may aggravate pathogenetic condition.