Health and medicine
- How do you know if someone is having a stroke: Think FAST!
- Common stroke signs and symptoms
- Diagnosing strokes by history and physical exam
- Diagnosing strokes with imaging CT, MRI, and Angiography
- Diagnosing strokes with lab tests
- Acute treatment of stroke with medications
- Treatment of stroke with interventions
- Preventing further strokes
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- how do they guide the wire up th blood vessel, and what happens if they accientally poked a hole in the blood vessel? With the suction method of removing the clot, Will it suck up some of the blood? What if the clot is very large and clogs up the tube? What if it sucks up too much blood?
Sorry that there are so many questions, but I am really, very curious.(4 votes)
- 1. The people who put the wire in are very talented and have probably trained themselves for such an occasion.
2. The suction thing should be close enough to the clot that it won't suck up that much blood. It probably would though.
3. Clots are made up of cholesterol and RBCs so it should be pretty easy just to poke a hole through.
4. Isn't that part of the second question?
(No, if you wanted the answer.)(1 vote)
- At6:46, do they remove the clot? If so how? Or does the body somehow remove it?(1 vote)
- For transient ischaemic stroke (mini stroke): blood supply to the brain is interrupted for a short time. The stroke is temporary and resolves itself. No evidence of infarction but important as it increases risk of another stroke.
For acute ischaemic stroke:
- Given Intravenous thrombolysis (IV tPA) within 4.5 hours of onset of symptoms, the earlier treatment has better outcome. Side effect is bleeding incl. intracranial haem. Therefore, blood pressure and neurological status need to be monitored for 24hrs.
- Given Endovascular thrombectomy within 6hrs of onset of symptoms or when IV thrombolysis is contraindicated or when patient presents too late for IV thrombolysis. Highly effective for patient who present 6-24hrs after onset of symptoms.
- Aspirin has a modest benefit when given within 48 hours of acute ischaemic stroke, and is routinely used. Do not give aspirin until brain imaging excludes intracranial haemorrhage. If the patient has received alteplase, withhold aspirin for 24 hours and do not start until follow-up imaging excludes haemorrhage.
Lifesyle and (antiplatelet/anticoagulant/blood pressure lowering/cholesterol lowering drugs)
- Why didn't they talk about tPA as a means to treat ischemic strokes?(1 vote)
- Due to the extremely small timeframe in which a patient is eligible to receive rtPA, it is estimated that only 3% to 5% of stroke sufferers reach a hospital in time to be considered for this treatment
I think that is why they don't talk about that much. o~O(1 vote)
- Does the clot created with coil embolization ever get degraded?(1 vote)
- [Voiceover] So really the main sort of underlying goal of stroke treatment is really to save as much brain tissue as possible. As you probably thought, right? Because by saving the maximum amount of brain tissue, the idea is that we only lose a minimal amount of function, of bodily function, movement, vision, sensation, taste even. So, you might remember that in any ischemic stroke there's a core area of neurons right at the site of the blood vessel obstruction, so there's brain tissue there that'll usually be irreversibly damaged within a few minutes of losing their blood supply. So, that's not great, but the good news is that there's salvageable brain tissue surrounding that core called the penumbra. So, this is an area where blood profusion has gone down because of the blockage here, but since it's still getting oxygen sort of peripherally from these blood vessels in the areas around it, these penumbra neurons don't die off right away, and if the person gets quick enough treatment then the penumbra neurons don't die off at all in most cases, the penumbra is savable. So, when someone comes in having had a stroke, the healthcare team often is thinking, "Alright, let's get down to business and "try to save the core if possible, "and let's definitely save that penumbra before "it's too late." So, with all that said, what sort of treatment can you get after a stroke? Well, remember that depends on what type of stroke you've had, ischemic or hemorrhagic. And with ischemic strokes you're usually given aspirin to prevent new clots from forming and thromobylics which try to break up the existing clot. And with hemorrhagic it's more about managing symptoms and potential complications in the initial phases of this stroke. Sometimes with an antihypertensive to lower blood pressure, and thus the amount of bleeding that's happening in the brain, and sometimes with an anticonvulsant to prevent any possible seizures, and sometimes with drugs to reduce swelling in the brain. So a few different medication options for these two types of strokes, but what else can be done? I mean, we've all seen McDreamy the neurosurgeon rush into the O.R. with his fancy hair, and his "it's a great day to save lives" spiel, what's he up to? By the way, he's the neurosurgeon from the thrilling drama "Grey's Anatomy". In the case of ischemic strokes, the surgeons won't usually be called to surgery unless the patient isn't responding to thrombolytics. So thrombolytics are usually tried first if the patient's still within the few hour window that they work best in. Otherwise if the surgeons are treating a patient with an ischemic stroke, they might be doing one of a few different but similar types of procedures with the ultimate goal of removing the clot that causes a stroke. So, one little device that they might use is called the "MERCI Retriever", and this was actually the first ever little gadget that was approved for clot removal after ischemic stroke. So, let's look at what MERCI stands for to get an idea of how it works. MERCI's an acronym, right? So it stands for Mechanical Embolus Removal in Cerebral ischemia. And how does it work? Well, let's just look at the general idea instead of bogging you down with all the technical details here. So, essentially what happens is that as part of this procedure a surgeon will insert a little wire into an artery and sort of thread it up into the brain, guide it along the arteries and get up into the brain here. And then the wire gets pushed just past the clot and that thing in blue there is actually a little sheath, the wire is actually inside the sheath, and then when the sheath gets retracted the wire starts to actually coil up on its own. And then as the wire is slowly retracted, as you can probably imagine it'll sort of catch on to the clot, it'll grab onto the clot nice and tight. And then the wire and the clot together they're both removed, and now blood can perfuse this area again and try to save all this brain tissue here. So that's MERCI retrieval, it's pretty cool stuff. And another way that ischemic strokes can be treated surgically is with suction. So how does that work? Well again here, same sort of deal. A tube goes into the artery and from here a little wire is put through the tube and positioned so it's right behind the clot. Then this tube sort of turns into a little vacuum cleaner that starts to suck in, and while it's sucking in, a wire gets pushed back and forth a few times through this clot to break it up. And all the little pieces that break off and eventually the whole thing, the whole clot gets sucked into this little vacuum here. So that's the suction method. And so there's a few other little variations on these two procedures for clot removal, you know, some using little mesh tubes called "stents" and some others with some different mechanisms but I'll leave it at this for now. So those two that we just talked about, those are treatments for ischemic strokes, but if our surgeon was treating a hemorrhagic stroke where one of the major goals is to control the bleeding, he might be doing some other things, some different procedures. So there's one called "aneurysm clipping". And what that is is, well we know that if an aneurysm in the brain bursts or sort of ruptures, then it'll start to spill blood out into the brain space right? Well, one way to fix that is for the surgeon to place a clip that kind of looks like this thing here, it's like a metal clip that then gets clamped on to the base of the aneurysm. So now that clip has blocked blood from coming through here and spilling out, so now blood can just continue along its merry little way, right? So, that's one way to treat a hemorrhagic stroke with these clips. Another procedure a neurosurgeon might do, and again this is in cases where a hemorrhage was caused by a burst aneurysm, is something called "Coil Embolization", and in coil embolization you'll kinda see why this name is fitting in a minute here. The surgeon will insert a little tube into the arterial system again, we're back to the tubes again so it'll get threaded up into the cerebral arteries until it's basically right inside the aneurysm right at the mouth of the aneurysm. And then, this flexible little wire gets threaded in through the tube and it starts to now coil up inside the dilated out part of the artery, the aneurysm here. And then more and more wire gets pushed in through the tube and into the aneurysm and it just coils and coils and coils. And eventually blood now can't even really enter that aneurysm even if it wanted to. So, two things. One, blood can now start to clot right? It can start to clot onto all this material in the aneurysm here and stop any bleeding from happening, so awesome, thumbs up. And two, blood in this artery here now it doesn't even have the option to duck up into this aneurysm and cause trouble anymore because of this clotted up coil. So now blood just continues to go about its business I guess down over this way. So, double thumbs up. So, those are some of the surgical interventions for ischemic and hemorrhagic stroke treatment.