Effect of new therapy of 20 AA compound amino acid plus high dose of vitamin B6 on acute lung injury induced by smoke inhalation in airtight cabins

Objective To evaluate the effect of a new therapy of 20AA compound amino acid injection plus high-dose vitamin B6 on acute lung injury induced by smoke inhalation in airtight cabins. Methods A total of 48 male SD rats were randomly divided into control group, injury group and treatment group, with 16 rats per group. Rats in the control group inhaled the fresh air freely and were injected intraperitoneally with 70 mL/kg physiological saline for three days. Rats in the injury group were injected intraperitoneally with 70 mL/kg physiological saline for three days after nose-only smoke inhalation for 10 minutes. Rats in the treatment group were injected intraperitoneally with 50 mL/kg 20AA compound amino acid injection plus 1 g/kg vitamin B6 (50 mg/mL) for three days after nose-only smoke inhalation for 10 minutes. Survival time and poisoning manifestations, lung function, pathological changes and lung wet-to-dry weight (W/D) ratio were observed and compared in three group. Results After smoke inhalation, breathing difficulties and some mental symptoms were observed immediately. Compared with the injury group, the mortality in the treatment group was increased (60% vs 40%), while the difference of survival time between the injury group and treatment group was not statistically significant (χ2=0.684, P=0.165). Lung edema and diffuse hemorrhage were observed in rats after smoke inhalation, and the degree of lung injury in the treatment group was lower than that in the injury group. Lung W/D ratio in the injury group was increased significantly compared with the control group [(5.02±0.13) vs (4.71±0.13), P=0.003]. W/D ratio in the treatment group was decreased significantly compared with the injury group [(4.76±0.18) vs (5.02±0.13), P=0.012]. PAU in the injury group was increased significantly compared with the control group [(1.93±0.58) vs (1.33±0.17), P=0.027]. PAU and EF50 in the treatment group were decreased significantly compared with the injury group [(1.29±0.43) vs (1.93±0.58), P=0.027; (0.58±0.15) mL/sec vs (1.19±0.40) mL/sec, P=0.035]. Conclusion The treatment of 20AA compound amino acid injection plus high-dose vitamin B6 can significantly improve the lung function and alleviate acute lung injury induced by smoke inhalation However, the mortality of rats is increased after smoke inhalation because of intolerance of the large dose of intraperitoneal injection of above liquids. Key words: Airtight cabin; Smoke inhalation; Acute lung injury; Compound amino acid; Vitamin B6