A Cadaver-based Study Using Surface Landmarking as the Tool to Guide Resuscitative Endovascular Balloon Occlusion of the Aorta Placement

Objective: Noncompressible truncal hemorrhage is a leading cause of preventable trauma-related death. Resuscitative endovascular balloon occlusion of the aorta (REBOA) is effective for temporary hemorrhage control but typically relies on imaging, limiting its use in resource-constrained settings. This study evaluates the accuracy of surface anatomical landmarks for Zone I REBOA placement. Materials and Methods: A cadaveric study was performed on 20 human cadavers. External distances from bilateral femoral artery access sites to the xiphoid process, midsternum, and suprasternal notch were measured. A REBOA catheter was advanced according to these measurements, and balloon position was confirmed by direct aortic visualization. The primary outcome was correct landing-zone (Zone I) placement. The secondary outcomes included distal safety margin (DSM), proximal safety margin (PSM), and distance to catheter tip (DCT). Statistical analysis included Cochran’s Q -test and McNemar’s exact test for categorical variables and repeated-measures analysis of variance for continuous variables. Results: Midsternum achieved 100% correct Zone I placement, compared with 45% for xiphoid and 60% for suprasternal notch ( P = 0.0046). Pairwise analysis confirmed superiority of the midsternum over xiphoid ( P = 0.00098) and suprasternal notch ( P = 0.00781). Xiphoid produced the greatest DSM and DCT, while suprasternal notch yielded the greatest PSM; however, these were associated with systematic misplacement. No significant differences were observed between right and left femoral approaches. Conclusions: Midsternal landmark-guided REBOA placement demonstrated the highest accuracy and reproducibility for Zone I deployment in this cadaveric model and may serve as a practical adjunct when imaging is unavailable or delayed.