Plasmapheresis is to remove, treat, and exchange blood plasma for other plasma or something else (i.e. albumin). I am going to focus on the exchange component called "plasma exchange" or even sexier: PLEX. This is typically used to treat various disorders of the immune system like TTP, Guillain-Barre, etc.
Could this work for COVID?
First of all, this is not a treatment for the virus itself. This will not be a viral load monitoring type therapy. This is intended to treat the cytokine storm and systemic response. What PLEX does is "remove inflammatory cytokines, stabilizing endothelial membranes, and resetting the hypercoagulable state".
The paper, which you should download and read for yourself, states that PLEX was used in a small number of patients during the H1N1 outbreak which had a full recovery. The authors are trialing this modality at the moment and have a paper that's cooking and is currently undergoing peer-review for publication. I tip my hat to the fact that they propensity matched their s/p PLEX patients to similar patients with similar illness who received standard of care. I wish the HCQ/azithro studies, remdesivir, and FFP studies to date would have done this but they didn't. Sigh.
Based on the experience of the group, they are using PLEX earlier in the disease course rather than later for better outcomes. They're working on a larger trial as well. Seems hopeful.
Cons:
Adverse effects/Caveats/concerns: patients will need a dialysis catheter. More bleeding when placing the catheter versus a traditional line but given that most patients end up on renal replacement therapy anyway, this may not matter. These prothrombotic patients may potentially clot off this circuit.
This is also a big machine that needs to be placed in a patients room. Concerns exist for cleaning the machine.
Some patients also develop hypotension and transfusion reactions.
As an aside, the Critical Care Medicine world is TINY! The author of the cited article trained at the same fellowship program I did and I interviewed at a place where he used to work. He's one brilliant dude. Everyone always loved working with him and sung his praises left and right. I picked up on his great energy myself immediately upon meeting him in person.
Keith, P., Day, M., Perkins, L. et al. A novel treatment approach to the novel coronavirus: an argument for the use of therapeutic plasma exchange for fulminant COVID-19. Crit Care 24, 128 (2020). https://doi.org/10.1186/s13054-020-2836-4
This data is current as of 4/13/2020
Link to Article
Link to FREE PDF
Link to Pre-pub article
