Clinical study on the risk factor and mechanical ventilation with low volume plus positive end-expiratory pressure in treatment of pulmonary injury complicated with acute respiratory distress syndrome

Objective To investigate the risk factors of acute respiratory distress syndrome(ARDS) and the therapeutic effect of mechanical ventilation with low volume plus PEEP on ARDS.Methods 538 patients with severe thoracic trauma were selected in this study. There were 455 male and 103 female with the mean age 52 years.The injured degree was evaluated according to AIS90-ISS grade. The factors correlated to ARDS were analyzed to assess the influence on tendency of ARDS. There were 31 patients who were diagnosed as ARDS. The convention ventilation and ventilation with low volume+ PEEP mode were performed in these patients. The parameters of blood gas, the incidence of ventilator associated pneumonia (VAP) and ventilation inducing lung injury (VILI), the attack time and incidence of multi-organ dysfunction syndrome (MODS) were observed. Results (1)The incidence of ARDS obviously increased when the parameters of respiration, blood pressure and blood-gas were abnormal(P0.01), and when which were complicated with rib fracture, pulmonary contuse,hemopneumothorax,injury of abdomen organs, extremity or pelvis fracture and chronic obstructive pulmonary disease,the incidence of ARDS increased significantly (P0.01). 2. In 31 patients with ARDS, there was no significantly difference in SaO2 and PaO2 between group A and group B(P0.05),however, PaCO2 in group B was significantly higher than that in group A (P0.01).The incidence of VILI and VAP in group B was also lower than that in group A (P0.01). There was no significantly difference in incidence of MODS between group A and group B (P0.05). It was easier for group B than group A to postpotne he attack time of MODS (P0.05).Conclusion (1)High age, shock, dyspnea, multi-fracture of rib, pulmonary contuse, severe hemopneumothorax, injury of abdomen organs, complications of respiratory system and levels of ISS are high risk factors influencing ARDS after thoracic trauma.(2)The mechanicalventilation with low volume plus PEEP fails to improve effect of oxygenation in the course of treatment of ARDS after thoracic trauma. Hemodynamic parameters are not affectd by PEEP (5～18 cm H2O).The mechanical ventilation with low volume plus PEEP is suitable to be used to treat ARDS after thoracic trauma by decreasing the incidence of VAP and VILI and delaying the attack time of ARDS.