Background
Resuscitative endovascular balloon occlusion of the aorta (REBOA) is an emerging and potentially life-saving procedure, necessitating qualified operators in an increasing number of centres. The procedure shares technical elements with other vascular access procedures using the Seldinger technique, which is mastered by doctors not only in endovascular specialties but also in trauma surgery, emergency medicine, and anaesthesiology. We hypothesised that doctors mastering the Seldinger technique (experienced anaesthesiologist) would learn the technical aspects of REBOA with limited training and remain technically superior to doctors unfamiliar with the Seldinger technique (novice residents) given similar training.

Methods
This was a prospective trial of an educational intervention. Three groups of doctors were enroled: novice residents, experienced anaesthesiologists, and endovascular experts. The novices and the anaesthesiologists completed 2.5 h of simulation-based REBOA training. Their skills were tested before and 8–12 weeks after training using a standardised simulated scenario. The endovascular experts, constituting a reference group, were equivalently tested. All performances were video recorded and rated by three blinded experts using a validated assessment tool for REBOA (REBOA-RATE). Performances were compared between groups and with a previously published pass/fail cutoff.

Results
Sixteen novices, 13 board-certified specialists in anaesthesiology, and 13 endovascular experts participated. Before training, the anaesthesiologists outperformed the novices by 30 percentage points of the maximum REBOA-RATE score (56% (SD 14.0) vs 26% (SD 17%), p<0.01). After training, there was no difference in skills between the two groups (78% (SD 11%) vs 78 (SD 14%), p = 0.93). Neither group reached the endovascular experts' skill level (89% (SD 7%), p<0.05).

Conclusion
For doctors mastering the Seldinger technique, there was an initial inter-procedural transfer of skills advantage when performing REBOA. However, after identical simulation-based training, novices performed equally well to anaesthesiologists, indicating that vascular access experience is not a prerequisite to learning the technical aspects of REBOA. Both groups would need more training to reach technical proficiency.