Abstract:
Objective To screen and evaluate the therapeutic effect of various combined treatments on acute lung injury (ALI) of rats induced by smoke inhalation in military airtight cabins.
Methods A total of 78 male SD rats were randomly divided into control group (Group A), injury group (Group B), single treatment groups (Groups C-F) and combined treatment groups (Groups G-M), with 6 rats per group. Groups C-F were treated with oxygen inhalation, heparin sodium nebulization, dexamethasone (Dex) or N-acetylcysteine (NAC) pre-injection, respectively, while Groups G-M were treated with a combination of two or more therapeutic measures above. Blood gas [arterial partial pressure of oxygen (PaO2), arterial partial pressure of carbon dioxide (PaCO2) and pH], carbon oxygen hemoglobin (COHb) and its clearance rate (CCR), lung pathological changes, lung wet-to-dry weight ratio (W/D), pulmonary permeability index (PPI), glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) activity and the content of malonaldehyde (MDA) and nitric oxide (NO) were measured at 24 h post-exposure to evaluate the effects of the various therapeutic measures.
Results Compared with Group B, the PaO2 was increased significantly in Groups G, H and J [(89.1±11.5) mmHg vs (106.0±9.2) mmHg, (108.1±10.9) mmHg and (108.1±4.3) mmHg, P<0.01 or 0.05]. CCR in Groups G-M was significantly higher than that in Group B (P<0.01 or 0.05). Lung pathological score in Groups G~M as decreased significantly compared with Group B (P<0.01). PPI in Group E and M was decreased significantly compared with Group B (2.42±0.38, 1.96±0.91 vs 7.02±1.05, P<0.01). W/D in Groups H, J, L and M was decreased significantly compared with Group B (4.63±0.08, 4.58±0.06, 4.47±0.14, 4.49±0.13 vs 4.88±0.21, P<0.01 or 0.05). GSH-Px activity was significantly increased in Groups G, I, K, L and M compared with Group B [(108.1±3.5)U/mgprot, (125.0±6.3) U/mgprot, (151.2±29.6)U/mgprot, (125.1±25.6)U/mgprot, (139.4±30.0)U/mgprot vs (95.8±12.1)U/mgprot, P<0.01 or 0.05)]. SOD activity significantly was increased in Groups G, J, K, L and M and the content of MDA significantly decreased in Groups G, H, I, J and L compared with Group B (P<0.01 or 0.05). The content of NO was decreased significantly in Groups G~M compared with Group B (P<0.01 or 0.05). The indices related with ALI which could be ameliorated with treatments were the most in Group M among Groups G-M and the semi quantitative score was highest in Group M.
Conclusion The combined treatment of NAC and Dex pre-injection, high concentration of heparin sodium nebulization and oxygen inhalation is the most effective and comprehensive therapy for ALI induced by smoke inhalation in rats among different combinations.
Key words:
Military airtight cabin,
Fire,
Smoke inhalation,
Inhalation lung injury,
Therapeutic measure
Lei Sun, Sheng Chen, Ying Cai, Hui An, Lin Ao, Huan Yang, Chengyu Tao, Jinyi Liu, Jia Cao. Effect of combined treatments on acute lung injury induced by smoke inhalation in military airtight cabins in rats[J]. Chinese Journal of Hygiene Rescue(Electronic Edition), 2017, 03(02): 79-87.