Original articles
QU Jinquan, YANG Xinyue, LI Jiajia, SUN Jiu, LIANG Feixing, SELIMU·Xirennayi, WANG Yan, LIU Jiangwei
Objective To establish a stable and reproducible animal model of abdominal intestinal firearm penetrating injury in a cold high-altitude environment. Methods Twenty landrace pigs were randomly and equally assigned to a low-altitude normal temperature (LN) group and a high-altitude cold (HC) group. The HC group was placed in a cold environment at high altitudes, and the LN group was placed in a normal-temperature environment at low altitudes. They were raised for 48 hours respectively. After anesthesia, they were suspended on the shooting range, and the right lower abdomen of the experimental pigs was shot with a gun. After injury, they were simply bandaged and transported back to the laboratory for observation in the normal temperature environment of the low altitudes. The vital signs and injuries at 0, 2, 4, 8, 12 and 24 h and 24 h survival rates of experimental pigs were compared. Laparotomy was immediately performed on the dead pigs and the experimental pigs still alive at 24 h to explore the injuries and observe the pathology of the small intestine and colon. Results The 24 h survival rate of the HC group was 70%, with no statistically significant difference compared to the LN group's 90% (P>; 0.05). After the injury, the body temperature of both groups gradually increased. The body temperature of the HC group was significantly higher than the LN group at 0, 2, 4 and 8 h time points (P<; 0.001), and the LN group exceeded the HC group at 24 h (P<; 0.05). Both groups showed an initial increase followed by a decrease in heart rate, with the HC group significantly higher than the LN group only at 0 h (P<; 0.01), and no statistically significant differences were observed at other time points (P>; 0.05). Both groups showed an early increase and later decrease in respiratory rate, with the HC group higher than the LN group at 0, 4, 8, 12 and 24 h (P<; 0.05 or P<; 0.001). There was no statistically significant difference (P>; 0.05) between the HC group and the LN group in small intestine rupture, small intestine contusion, mesenteric injury, colon rupture and wound diameter. The pathology of the small intestine and colon in the HC group showed extensive necrosis and shedding of the mucosa layer, severe congestion and edema of the submucosa, and extensive lymphocyte infiltration. The LN group also showed similar symptoms but to a lesser extent. Conclusion This study established a pig model of abdominal firearm intestinal perforation injury in a cold environment at high-altitudes. The model has strong operability and stable damage, which can provide a reference for subsequent research.