ObjectiveTo observe the clinical efficacy of ulinastatin combined with low-dose arginine vasopressin in treating severe pulmonary contusion. MethodSixty patients with severe pulmonary contusion were enrolled in our hospital between April 2012 to June 2014 year. All the patients were randomly divided into three groups. They were respectively defined as a routine treatment group (group A, n=20), an ulinastatin treatment group (group B, n=20), and a combined treatment group (group C, n=20). The respiratory frequency (RR), oxygenation index, partial pressure of carbon dioxide (PaCO2), the change of chest X-ray and the change of serum interleukin-6 (IL-6), IL-8 levels were compared among three groups before and after therapy. ResultThe respiration frequency(RR) and the concentration of serum IL-6, IL-8 levels were decreased in the group C before and after treatment with statistical differences (P=0.000, 0.000, 0.000). PaO2/FiO2 and PaCO2 were significantly increased in the group C before and after treatment (P=0.000, 0.000). After treatment for 7 d, the respiration frequency (RR) and the concentration of serum IL-6, IL-8 of patients in the group B decreased significantly compared with those in the group A (P=0.000, 0.043, 0.000). While PaO2/FiO2, PaCO 2 and the score of chest X-ray increased significantly in the group B (P=0.010, 0.000, 0.000). Compared with those in the group B, RR and the concentration of serum IL-6, IL-8 of patients in the group C decreased significantly (P=0.000, 0.045, 0.000), while PaO2/FiO2, PaCO2 and the score of chest X-ray increased significantly (P=0.043, 0.010, 0.001). ConclusionUlinastatin combined with low-dose arginine vasopressin shows obvious effects in the patients with severe pulmonary contusion. And its therapeutical effects are better than that of the other two treatment options.