What is the best way to get rid of confounding?
Randomization.
The process of randomization ensures that there are equal amounts of known and unknown confounders in each group. Problems solved… theoretically.
So here is the first randomized clinical trial of REBOA in trauma!
The UK-REBOA RCT was conducted in 16 major trauma centers in the UK. Patients with exsanguinating hemorrhage were enrolled over 4+ years.
The primary outcome was all-cause mortality at 90 days. There were lots of secondary outcomes.
Results?
90 patients were enrolled almost all (97%) with blunt trauma. As expected, they were super sick with a median injury severity score (ISS) of 41.
In the end, the trial was stopped for harm. Mortality was 54% with REBOA vs. 42% in the standard care arm. Number needed to kill (NNK) is 8. In addition, all the secondary outcomes and bleeding seemed to be worse with REBOA.
Does this signal the death of REBOA?
Probably not.
Unfortunately, this paper has lots of limitations. The biggest of which is only 19 out of 46 patients randomized to REBOA got the device inserted and balloon inflated. It is hard to demonstrate a treatment effect when most patients don’t get the treatment. But perhaps this shows the real-world difficulties of performing REBOA.
Critics of this paper will highlight many other issues: training of providers, time delays, specific device used, small numbers, stopped early, baseline differences favored the control arm, no penetrating trauma, etc.
Despite all the issues, I think there is a big take home point.
REBOA is very hard to study.
These authors went to great efforts. They included 16 centers over 4+ years and still they had major issues. In the end, I doubt we will see much better evidence anytime soon. Nevertheless, I think we will see a shift away from REBOA... don't believe the hype.
Covering:
Jansen, JO, Hudson J, Cochran C, et al. Emergency Department Resuscitative Endovascular Balloon Occlusion of the Aorta in Trauma Patients with Exsanguinating Hemorrhage: The UK-REBOA Randomized Clinical Trail. JAMA. 2023;330(19):1862-1871. [Link to article]