Establishment of a rabbit model of acute lung injury induced by one-lung ventilation

Objective To establish a rabbit model of acute lung injury induced by one-lung ventilation (OLV) .Methods Sixteen New Zealand white rabbits weighing 2.3-2.7 kg were randomly divided into 2 groups (n=8 each):conventional tidal volume(VT) group (group Ⅰ) and high VT group (group Ⅱ).All the rabbits were tracheostomized and a tracheal tube was inserted into the right bronchus for right lung ventilation in the two groups. VT was set at 6 ml/kg in group Ⅰ and at 12 ml/kg in group Ⅱ and the other ventilatory parameters were the same in the two groups (FiO2 50% , RR 40 bpm, I∶E=1∶2). Immediately before OLV(T0) and at 1, 2 and 3 h of OLV (T1-3), peak airway pressure was measured and arterial blood samples were taken for blood gas analysis and oxygenation index (OI) was calculated. The animals were sacrificed at 3 h of OLV and lung tissues obtained for microscopic examination.The lung injury was scored. W/D lung weight ratio was calculated. Bron-choalveolar lavage fluid (BALF) was collected for measurement of protein concentrations and neutrophil counts. Results The peak airway pressure was significantly higher at T1-3 in group Ⅱ and OI was significantly lower at T2,3 in the two groups than those at T0(P＜0.05) .W/D lung weight ratio and lung injury scores of the right lung were significantly lower than those of the left lung in the two groups(P＜0.05).The peak airway pressure was significantly higher at T1-3, OI was significantly lower at T3, and W/D lung weight ratio, protein concentrations and neutrophil counts in BALF and lung injury scores of the right lung were significantly higher in group Ⅱ than in group Ⅰ(P＜0.05). Conclusion OLV with VT of 12 ml/kg for 3 h can successfully establish a rabbit model of acute lung injury. Key words: Respiration, artificial;  Respiratory distress syndrome,adult;  Disease models,animal