Could plasma exchange help save the lives of COVID patients? Let’s straighten out some nomenclature first. We all have questions about what is what and there is much confusion. I personally like the say all these words roll off the tongue. Makes you sound smart when you say it. There’s more to it than what I am going to mention here, of course.
What is plasmapheresis used for?
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 Plasma Exchange 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 of plasma exchange in COVID:
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.
Where’s the data on plasma exchange in COVID? (Addended 7/31/20)
On 7/31/2020, the Journal of Critical Care released an abstract (I can’t get my hands on the full article at the time of this writing) about a pilot study looking at 10 patients consecutive with Severe COVID. An honest appraisal from me would include a deep analysis of the data but that is not accessible to me at this time.
Needless to say, these patients were quite sick. They all had ARDS with a P/F around 110, were in shock, had cytokine release syndrome, were on the ventilator and proned. They provided these patients with 5-7 sessions of therapeutic plasma exchange.
Per the abstract, these are the things that improved.
– Sequential Organ Function Assessment score
– PaO2/FiO2 ratio
– levels of lymphocytes
– total bilirubin
– lactate dehydrogenase
– ferritin
– C-reactive protein
– interleukin-6
Side effects from PLEX, you ask? None. They did note acute kidney injury in 10% of patients and pulmonary emboli in 20% of patients. It is worth considering what type of DVT prophylaxis or even full dose anticoagulation these patients were on.
The mortality at day 28 is 10%. 1 of the 10 patients died. I wish it was zero but I can go for this.
Citations:
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
Link to Article
Link to FREE PDF
Pre-pub article
F. Faqihi, A. Alharthy, M. Alodat, et al., Therapeutic plasma exchange in adult critically ill patients with life-threatening SARS-CoV-2 disease: A pilot study, Journal of Critical Care (2019), https://doi.org/10.1016/j.jcrc.2020.07.001
Link to Abstract
Click here for breakdowns of other COVID-19 Articles.
Check out this blog post in Podcast format!
New Papers regarding Plasma Exchange in COVID that you can check out.
08.08.2020
Gucyetmez, B., Atalan, H.K., Sertdemir, I. et al. Therapeutic plasma exchange in patients with COVID-19 pneumonia in intensive care unit: a retrospective study. Crit Care 24, 492 (2020). https://doi.org/10.1186/s13054-020-03215-8
Link to Article
Link to FULL FREE PDF