Gunshot model of junctional femoral artery hemorrhage in swine under ultrasonic guidance

Abstract Background In a combat setting, uncontrolled junctional hemorrhage constitutes a major source of potentially preventable deaths. It is very important to establish a model of massive hemorrhage of gunshot wound at junction area which can simulate field rescue conditions. Methods Picco monitoring was instrumented for the anesthetized Landrace pigs, and the right femoral artery was located by portable ultrasound. The pistol bullet hit the right femoral artery, resulting in an artery rupture. After 30 seconds of uncontrolled hemorrhage, the ballistic wound was filled with combat gauze (QuikClot) to stop bleeding in the BT group (n = 10). Combat gauze was used to stop bleeding when the mean arterial pressure (MAP) decreased by 30% in the MD group (n = 10). The sham-operated pigs (n = 10) underwent the same anesthetic and surgical procedures, but neither shooting nor gauze filling therapy was performed. Blood samples were taken 15 min before injury, and then 10 min, 30 min, and 60 min after the injury. Results Histologic anatomy indicated that the right femoral artery and vein were completely ruptured in all 20 swine of MD and BT groups. The blood loss of pre-tamponade (4.97 ± 2.47 mL/kg vs 18.26 ± 3.47 mL/kg, P < 0.001), pro-tamponade (4.58 ± 1.49 mL/kg vs 7.20 ± 1.99 mL/kg, P = 0.004) and the total amount of bleeding (9.54 ± 3.80 mL/kg vs 25.46 ± 3.68 mL/kg, P < 0.001) in MD group were more than those in BT group. There were differences in body temperature, PH, PT, LAC of MD group compared with BT and SHAM groups 60 minutes after injury (all P < 0.0167). The survival time of MD group was shorter than that of BT group (P = 0.029). Conclusion We established a reliable gunshot model of junctional hemorrhage in swine, which had high accuracy for femoral arterial rupture under ultrasonic guidance and provided consistent and reproducible field-simulation conditions. In this junctional hemorrhage model, blood loss of 30-second free bleeding did not meet the criteria for shock. The MAP decrease of 30% emerged as a better predictor of a successful shock model.