Zone III REBOA and the COBRA-OS™: Safety of Inadvertent Iliac Artery Device Deployment

Background: REBOA is an emerging technique in trauma. However, inadvertent iliac artery balloon inflation can lead to complications. This study aims to investigate the safety characteristics of the COBRA-OS™ compared to a 7 Fr commercially available device during purposeful iliac artery balloon overinflation. Methods:  In vitro: the COBRA-OS™ was inflated in explanted porcine iliac arteries and intentionally overinflated until balloon or vessel rupture occurred. In vivo: the COBRA-OS™ and 7 Fr device were deployed in the iliac arteries and intentionally overinflated until rupture of the balloon or blood vessel. Results: In vitro: an average volume of 1mL was required for occlusion using the COBRA-OS™ and the mean balloon rupture volume was 32.5mL. The COBRA-OS™ partially migrated into the aorta in all cases. In vivo: the COBRA-OS™ and 7 Fr device occluded the iliac arteries with a mean volume of 3.5 mL.  Overinflation resulted in no iliac ruptures with the COBRA-OS™ (mean balloon rupture volume = 10mL). Overinflation with the 7 Fr device resulted in 1 iliac rupture at 5mL. The other two 7 Fr devices had a mean balloon rupture volume of 5 mL. All COBRA-OS™ devices moved partially up into the aorta during inflation while all 7 Fr devices remained in the iliac artery. Conclusions: The COBRA-OS™ allows for significant overinflation when deployed in the common iliac artery of a porcine model due to its unique design. This ultimately may help to prevent balloon and blood vessel rupture during clinical use, however further studies are required.