Objective:To evaluate the hemostatic effects of our self-designed pelvic band with inflatable balloon in a swine model of hemodynamically unstable pelvic fracture.Methods:"Open-book like" fractures were created with the external iliac blood vessels exposed in 24 12-month-old female Bama miniature pigs which were randomly divided into 4 groups ( n=6). Group C (the control group) was subjected to no treatment other than exposure of the external iliac blood vessels, group D to no treatment following destruction of the external iliac blood vessels, group T1 to fixation with simple pelvic band after destruction of the external iliac blood vessels, and group T2 to fixation with our self-designed pelvic band with inflatable balloon after destruction of the external iliac blood vessels. The 4 groups were compared in terms of 40-min survival rate, bladder pressure, peak lactate value, total blood loss, bleeding rate, infusion rate, and angiographic images. Results:There was no significant difference in the baseline indexes among the 4 groups before experiment, showing comparability ( P>0.05). The 40-min survival rate in group T2 was 83.3% (5/6), significantly higher than that in groups D and T1 [0% (0/6) and 0% (0/6)] ( P<0.05). There were no significant differences among groups C, D, T1 and T2 in bladder pressure [(6.67±1.03) mmHg, (5.83±1.94) mmHg, (6.00±1.55) mmHg, and (6.00±1.10) mmHg] or in total blood loss among groups D, T1 and T2[(1,198.0±182.9) mL, (1,252.0±148.4) mL, and (1,150.0±125.7) mL] (all P>0.05). The peak lactate value in group T2 [(2.26±0.24) mmol/L] was significantly lower than that in group D [(5.00±0.60) mmol/L] and group T1 [(3.86±0.57) mmol/L], and the bleeding rate and infusion rate in group T2 [(25.83±5.49) mL/min and (26.00±4.69) mL/min] were also significantly lower than those in group D [(83.50±19.85) mL/min and (71.50±29.11) mL/min] and group T1 [(54.17±15.59) mL/min and (54.17±8.98) mL/min] (all P<0.05). Angiography showed contrast agent extravasation in group T2, especially from the artery, but the extravasation speed in group T2 was significantly slower than that in group D. Conclusion:In a swine model of hemodynamically unstable pelvic fracture, our self-designed pelvic band with inflatable balloon has a definite hemostatic effect on vascular injury which is better than that of a simple pelvic band.