Background: Among potentially survivable combat casualties, more than 50% of fatal cases are due to truncal (abdominal and pelvic) hemorrhage. Endovascular therapy, is a minimally invasive technique that can be potentially applied in the field, and provide a temporal solution until a definitive therapy is given. It has been demonstrated that intra-aortic balloon occlusion can effectively control truncal bleeding, although, only short time frames (60-90 min) were tested. However, these time frames are irrelevant for pre-hospital treatment in combat casualties.
Aim: to develop a safe and effective method for endovascular control of pelvic bleeding, to be implanted in the pre-hospital setting with prolonged evacuation times.
Methods: Pelvic bleeding was induced in swine through an 8F arterial introducer sheath inserted via the femoral artery. Basic bleeding rate was measured. After 5 min of bleeding, an aortic CODA balloon was inflated below the renal arteries. Treatment time was 6 hours, followed by 30 minutes of follow up during reperfusion. Continuous blood pressure was measured above and below the balloon. Survival and reduction in bleeding rate vs. baseline were the primary safety and effectiveness outcomes, respectively.
Results: 6 animals were studied. All animals survived 6 hours of bleeding followed by 30 min of reperfusion. Mean baseline bleeding rate was 5,990±952 ml/hr at baseline, and was reduced to 889±326 ml/hr, a reduction of of 85% from baseline. Systolic blood pressure was 105 mmHg at baseline, 65 mmHg proximal to balloon occlusion and 17 mmHg distal to balloon during bleeding time. Potassium levels significantly increased from a baseline of 3.9±0.33 mmol/l at baseline to 6.8±0.54 after reperfusion, although no arrhythmias were observed.
Conclusions: Prolonged pelvic bleeding control with infra-renal aortic balloon occlusion is safe and effective in this animal model. Further study is needed however to evaluate the significance and consequence of hyperkalemia.
