tPA for Stroke. Again. Sorry about that.

Sorry to carry on about this, but I can’t help myself…

The other night SBS television in Australia aired a special on stroke (found online here)  It brought together some stroke survivors, neurologists, emergency doctors and so on to discuss stroke and stroke treatment.  Of course the issue of tPA for stroke reared it’s ugly head again and it is clear that the debate over this has not been settled. 

I’m not going to go on at length about the evidence for or against tPA for stroke.  Far smarter people than I have already done that; for an excellent, succinct and lucid discussion please read the post by the inimitable Michelle Johnston (@Eleytherius) over at Life in the Fastlane.  Or, for a deeper look, head over to SMARTEM to listen to Dave Newman’s epic podcast on the same.

If you can’t be bothered with that the TL:DR version is:  12 studies, 10 negative or harmful, remaining two have significant methodological flaws.  Ergo, jury still out.

However, I did want to comment on the show itself and some of the issues I think it raised.

First of all it appeared to me that SBS focused exclusively on the feel-good stories of people who have done well following their tPA for stroke.  There was no counterpoint of the patients who have had catastrophic brain bleeds following tPA.  This is something that I noticed with an earlier SBS special on advances in cardiac arrest care where a very skewed vision of survival was presented.

This same skewed, positive outlook pervaded this episode.  I don’t want to sound pessimistic as stroke patients can do well, however I feel that this presented to the general public an unrealistic view of how well they may expect their loved ones to do after suffering strokes.  Bear in mind that for the lay-person these sorts of shows may be the only exposure they receive to these diseases, unless they are unfortunate enough to be on the wrong end of a clot.  This may make appropriate decision making difficult when their viewpoint is coloured by an unrealistic expectation of prognosis put forward by experts (no, I have no evidence for this, I’m just pontificating).  In particular the apparent miraculous improvement at the end of the needle seemed a little heavily emphasized given that (as Dr Johnson points out) in the short term there is no apparent difference between tPA versus no tPA with any difference only becoming apparent after 30 days.

I was also very disappointed to see the debate around tPA being described as a “turf-war” between emergency physicians and neurologists.  I do not think that this is a helpful characterization of what is, in my eyes, a genuine debate on the science about a treatment that has a definite risk of harm attached to it.  It appeared to me to detract from the concerns of the emergency physicians and relegated them to a status of (as a later commentator described them on twitter) the equivalent of climate change skeptics.  The assertion from one of the neurologists that they just need to “get on with” treating patients made it seem that the EPs did not have the best interests of the patient at heart.  This is of course not the case.

Finally, I was interested to note that in discussions with the patients who had received tPA there did not appear to me to have been a great deal of discussion regarding the potential harms of tPA.  The patients interviewed professed to have either never having been told of these potential harms, or to have been given the impression that there was no real option except to have the tPA.  Of course memory can be a tricky thing and obviously in a stressful situation where damage has been done to the brain it may be unreliable, however it did seem to me at least that there was rather a degree of paternalism involved for these patients.  I trust that this would not be the case, but nonetheless it felt uncomfortably like it to me.

Ultimately I don’t believe that this show added anything to the debate surrounding stroke treatment.  The genuine concerns over the efficacy and safety of tPA were relegated by feel-good anecdote and I suspect that the public would feel that there is no issue or debate to had, and that tPA is a wonder drug.  This is disappointing as debate can be healthy and useful for health consumers.

I don’t know if tPA is good or bad.  I think the best that can be said for it is that we just don’t know given the current state of play.  There may be a subset of patients in certain situations in whom tPA is beneficial, but I do not know who they are or how we differentiate them.  I think that the blanket administration of tPA to all presumed occlusive strokes is probably not helpful.

This leaves me having to reconcile my skepticism with the organizationally mandated need to expedite the treatment of stroke patients with tPA.  This has made me uncomfortable to some degree in the past.  However I have come to accept that despite my misgivings about tPA, my part in stroke patient care is still important.  Even if tPA is not any use, what is useful (as Dave Newman points out) is the mobilizing of resources to care for a patient.  Even if any single intervention is not useful on it’s own, having a large number of resources brought to bear on a single patient/condition is helpful in some fashion.  We see this in trauma care, where the mobilization of a large amount of expert care in trauma centers results in better outcomes.  I like to think of it in some ways as a sort of Hawthorne effect such as we see in trials, where even if the treatment is standard, having more resources and oversight means that all patients do better.
In a similar vein, even if tPA does not help, we know that early intensive rehab and follow up care that comes from being in a specialist stroke center does.  Therefore I still see some value in maintaining the level of response to stroke we currently have, whilst letting smarter people than I nut out the best pharmacology to use.  It is sometimes an uneasy truce with my conscience, but nonetheless one that works for me.

Right, well unless something remarkable happens, like a large, non-industry funded, methodologically sound tPA trial that dramatically changes our understanding, I shall attempt not to get into matters that are above my head again.  Maybe…