I am fascinated by this ECMO cohort (atsjournals.org/doi/abs/10.116…): PF 70 on only 12 of PEEP, minimal proning. Mortality about 40%.
Even stepping outside my native skepticism about VV ECMO, these results seem to me to testify to rampant overuse. Two things to draw attention to:
1. Regarding the mortality, recall that patients who have independent morbidities contributing to their outcomes have been excluded. The exclusion of patients with comorbidities is more extreme I suspect than most ARDS trials. So a mortality of 40% doesn't even suggest
to me that there's likely to be a mortality benefit over non-VVECMO support. Careful conventional ventilation at experienced centers have achieved those mortality rates for years, no?
2. Regarding the empirical enrollment criteria, previously healthy patients with those numbers just don't seem to have failed conventional therapy. I would consider using high PEEP and/or proning alongside rigorously protocolized ventilator management using the ARMA protocol.
I'm aware that people like to say "get them early so that the ECMO will work", but the methodologist in me says that this is primarily enriching populations with patients who would have better outcomes without ECMO.
To be clear, I'm not an anti-ECMO ideologue. I like the idea, love machines and procedures, love stealing life from the jaws of death and can imagine that perhaps 5% of patients being put on ECMO for ARDS really are benefiting from it.
I just think it's worth calling out suspicious patterns in data and practice. And this fascinating multinational cohort strikes me as strongly suggestive of overuse. I'd love to learn more about cohorts reporting patients who have actually failed conventional therapy.
