Ben's situation is terrible.
ECMO requires anti-coagulants at very high levels. You need to keep clots from forming without inducing a brain bleed. Titration is difficult as situations can develop quickly.
ECMO, by it's very nature, induces clotting in the blood stream. Micro clots get stuck in the lungs and the brain and there's not much you can do about it. These brain injuries stack up and the longer you're on ECMO, the more damage you take.
The only thing worse than ECMO is needing it and not getting it.
I was a bit surprised he was even listed given his condition and I doubt he's listed at 1A or 1B status.
Organ transplant is a long, ugly road and I hope he and his family come out of it OK.