4 ms·

What this story leaves out is why we are moving away from thrombolytics - besides them kinda sucking. Once a clot has matured they tend to be useless, which is

What this story leaves out is why we are moving away from thrombolytics - besides them kinda sucking. Once a clot has matured they tend to be useless, which is part of why there’s a solid upper cap on time to administration. You cross a line where any clot they’re likely to bust isn’t one you want to bust. So, a window of a couple of hours. Urokinase doesn’t change that, to my knowledge. Surgical removal of the clot, on the other hand, has recently been shown to offer enormous benefit to at-risk tissue (tissue not yet dead but in the watershed area) 24 hours later, without risk of hitting the wrong clot. It’s no miracle either, but evidence is piling up that it’s got more Pros and fewer Cons. Thus, no one really following armchair hypotheses (one old non RCT trial not withstanding) about combining two increasingly undesirable drugs. I respect the guy’s thought and effort, and have to admit he might be right about their combined effectiveness, but this article leaves out a lot of the context as to -why- this isn’t getting attention. Writing a hagiography-by-omission is below what I’ve come to expect from statnews.

ntenenz 9y ago
For those interested, the DAWN Trial (http://www.nejm.org/doi/full/10.1056/NEJMoa1706442 http://www.nejm.org/doi/full/10.1056/NEJMoa1706442) provides more detail on the value of thrombectomy, especially in cases where the collateral circulation is strong.
- _0ffh 9y ago
  Very interesting, thank you! Unfortunately I don't quite know what to make of the recurring phrase "mismatch between clinical deficit and infarct". Could anyone enlighten me, please?
  - arkades 9y ago
    When a clot blocks off blood flow to an area of the brain you expect that area to die and, as a result, lose its function (“clinical deficit”). The blockage is an infarct; the downstream area suffocating is infarcted. When you look at the area of brain that should be downstream of a clot and therefore nonfunctional, that’s the “infarct volume”. It’s the volume of brain that we believe is infarcted. The “mismatch” is when we do a CT, find that, say, the chunk of your brain that moves your right hand is downstream from the infarct, but your right hand is still working. This suggests that that part of your brain has enough blood coming to it from other, less salient, arteries that it’s dying slowly instead of fast. That “mismatch” area is the one that, if we can go in and surgically pull out the clot, we can save.
    - kgc 9y ago
      This was really educational. Good vocab lesson. +1
      - arkades 9y ago
        My pleasure
worldburger 9y ago
+1. How does one come to such a conclusion if one is not a medically trained professional? I found your comment insightful, would you expand upon your own context to the topics of the article?
- goldenkey 9y ago
  Research, just like anything else. Doctors have to know a ton about a wide spectrum whereas a guy with time and a computer can pretty much run through the state of clot treatment in a couple of days to weeks.
  - arkades 9y ago
    Or, as in this case, being a doctor who is also a guy with a computer. :)
anitil 9y ago
'hagiography' - Thanks for a new word! ('a biography that treats its subject with undue reverence')
- dbasedweeb 9y ago
  If you’re into etymology at all, it’s worth knowing that originally a hagiography was the biography of a saint, focusing on their miracles.
  - rhaps0dy 9y ago
    I thought that it was still technically the biography of a saint, and was only used as anitil's definition by way of metaphor.
    - anitil 9y ago
      I wasn't sure which definition was common parlance so took a punt that the metaphor had overtaken the true meaning.
robbiep 9y ago
Whilst angioplasty or clot retrieval is the optimal treatment (have not seen evidence for clot retrieval for strokes in longer timeframes but will be interested to jump into some research tomorrow) in countries where there are enormous distances between tertiary referral centres (ie Australia) thrombolytic agents are still strongly used. Our ambulances are equipped with r-tPA or similar (there is a tendency to avoid streptokinase as rural/indigenous populations have high exposure to streptococcus/hx rheumatic fever and therefore high risk of added complications) and in the event of STEMIs can be administered en route to ED. Similarly many peripheral sites will administer tenecteplase or similar in Emergency Departments as there are almost no sites that are set up to perform out-of-hours angioplasty once you are out of the major cities; even less chance for neuro-radiological intervention, I think there are only 6 or 7 sites in the country and they are all in major cities. If his research does bear fruit, I could see it immediately becoming the standard of care in Australia outside of major centres
- thomasfedb 9y ago
  I'm a volunteer ambulance officer in Western Australia. We certainly don't carry thrombolytic agents. What we do have though is a protocol for getting stroke patients (with good predicted outcomes) into a helicopter or fixed-wing aircraft ASAP so they can get to a hospital with a thrombectomy (clot retrieval) service. If called promptly, then there shouldn't be many patients that we can't get to the right care within a suitable timeframe.
  - autokad 9y ago
    > "If called promptly, then there shouldn't be many patients that we can't get to the right care within a suitable timeframe." I worked with stroke centers, doctors, etc in building stroke access systems, and that doesn't fly with reality. Number 1, is that its hard for patients to recognize they are having a stroke. so "If called promptly" is a bit of unrealistic idealism. Although they say 4 hours, tPA administered after 1 hour has lost most of its benefit, and places that can do thrombectomy 24/7 (in US dedicated stroke centers) is not numerous. You are losing a lot of that hour just for time for the helicopter to warm up, find a spot, and land + your ambulance time getting to /stabilizing the patient. I'm sure the patients on your beat had suitable access, but that's a bit of selectivity bias no? In the US, although the majority of the population is within the golden hour, there are still a ton of population that does not have access to a stroke center. I find it extremely hard to believe that this is not the case in Australia - where I have heard stories of people getting a finger cut off and having to drive 3 hours to the nearest hospital.

ntenenz 9y ago

For those interested, the DAWN Trial (http://www.nejm.org/doi/full/10.1056/NEJMoa1706442 http://www.nejm.org/doi/full/10.1056/NEJMoa1706442) provides more detail on the value of thrombectomy, especially in cases where the collateral circulation is strong.

_0ffh 9y ago
Very interesting, thank you! Unfortunately I don't quite know what to make of the recurring phrase "mismatch between clinical deficit and infarct". Could anyone enlighten me, please?
- arkades 9y ago
  When a clot blocks off blood flow to an area of the brain you expect that area to die and, as a result, lose its function (“clinical deficit”). The blockage is an infarct; the downstream area suffocating is infarcted. When you look at the area of brain that should be downstream of a clot and therefore nonfunctional, that’s the “infarct volume”. It’s the volume of brain that we believe is infarcted. The “mismatch” is when we do a CT, find that, say, the chunk of your brain that moves your right hand is downstream from the infarct, but your right hand is still working. This suggests that that part of your brain has enough blood coming to it from other, less salient, arteries that it’s dying slowly instead of fast. That “mismatch” area is the one that, if we can go in and surgically pull out the clot, we can save.
  - kgc 9y ago
    This was really educational. Good vocab lesson. +1
    - arkades 9y ago
      My pleasure

worldburger 9y ago

+1. How does one come to such a conclusion if one is not a medically trained professional? I found your comment insightful, would you expand upon your own context to the topics of the article?

goldenkey 9y ago
Research, just like anything else. Doctors have to know a ton about a wide spectrum whereas a guy with time and a computer can pretty much run through the state of clot treatment in a couple of days to weeks.
- arkades 9y ago
  Or, as in this case, being a doctor who is also a guy with a computer. :)

anitil 9y ago

'hagiography' - Thanks for a new word! ('a biography that treats its subject with undue reverence')

dbasedweeb 9y ago
If you’re into etymology at all, it’s worth knowing that originally a hagiography was the biography of a saint, focusing on their miracles.
- rhaps0dy 9y ago
  I thought that it was still technically the biography of a saint, and was only used as anitil's definition by way of metaphor.
  - anitil 9y ago
    I wasn't sure which definition was common parlance so took a punt that the metaphor had overtaken the true meaning.

robbiep 9y ago

Whilst angioplasty or clot retrieval is the optimal treatment (have not seen evidence for clot retrieval for strokes in longer timeframes but will be interested to jump into some research tomorrow) in countries where there are enormous distances between tertiary referral centres (ie Australia) thrombolytic agents are still strongly used. Our ambulances are equipped with r-tPA or similar (there is a tendency to avoid streptokinase as rural/indigenous populations have high exposure to streptococcus/hx rheumatic fever and therefore high risk of added complications) and in the event of STEMIs can be administered en route to ED. Similarly many peripheral sites will administer tenecteplase or similar in Emergency Departments as there are almost no sites that are set up to perform out-of-hours angioplasty once you are out of the major cities; even less chance for neuro-radiological intervention, I think there are only 6 or 7 sites in the country and they are all in major cities. If his research does bear fruit, I could see it immediately becoming the standard of care in Australia outside of major centres

thomasfedb 9y ago
I'm a volunteer ambulance officer in Western Australia. We certainly don't carry thrombolytic agents. What we do have though is a protocol for getting stroke patients (with good predicted outcomes) into a helicopter or fixed-wing aircraft ASAP so they can get to a hospital with a thrombectomy (clot retrieval) service. If called promptly, then there shouldn't be many patients that we can't get to the right care within a suitable timeframe.
- autokad 9y ago
  > "If called promptly, then there shouldn't be many patients that we can't get to the right care within a suitable timeframe." I worked with stroke centers, doctors, etc in building stroke access systems, and that doesn't fly with reality. Number 1, is that its hard for patients to recognize they are having a stroke. so "If called promptly" is a bit of unrealistic idealism. Although they say 4 hours, tPA administered after 1 hour has lost most of its benefit, and places that can do thrombectomy 24/7 (in US dedicated stroke centers) is not numerous. You are losing a lot of that hour just for time for the helicopter to warm up, find a spot, and land + your ambulance time getting to /stabilizing the patient. I'm sure the patients on your beat had suitable access, but that's a bit of selectivity bias no? In the US, although the majority of the population is within the golden hour, there are still a ton of population that does not have access to a stroke center. I find it extremely hard to believe that this is not the case in Australia - where I have heard stories of people getting a finger cut off and having to drive 3 hours to the nearest hospital.