Deans' stroke musings

Changing stroke rehab and research worldwide now.Time is Brain!Just think of all the trillions and trillions of neurons that DIE each day because there are NO effective hyperacute therapies besides tPA(only 12% effective). I have 493 posts on hyperacute therapy, enough for researchers to spend decades proving them out. These are my personal ideas and blog on stroke rehabilitation and stroke research. Do not attempt any of these without checking with your medical provider. Unless you join me in agitating, when you need these therapies they won't be there.

What this blog is for:

Shortly after getting out of the hospital and getting NO information on the process or protocols of stroke rehabilitation and recovery I started searching on the internet and found that no other survivor received useful information. This is an attempt to cover all stroke rehabilitation information that should be readily available to survivors so they can talk with informed knowledge to their medical staff. It's quite disgusting that this information is not available from every stroke association and doctors group.
My back ground story is here:http://oc1dean.blogspot.com/2010/11/my-background-story_8.html

Monday, July 24, 2017

Why the Go-To Stroke Drug Can Fail

So with the 88% failure rate of tPA full recovery maybe other options exists. But since we have NO stroke leadership or strategy nothing will occur to solve this problem. It has been 21 years since this failure has been known, I don't expect anything to change for the next 21 years unless a lot of people die that are preventing new ideas from being considered.
  1. Magnetic nanopaerticles to direct tPA to the clot, size of bolus could be reduced lowering bleeding risk.
  2. Future of med devices: Nanorobots in your blood stream

    Use them to deliver tPA or drill thru the clot.

     
https://www.scientificamerican.com/article/why-the-go-to-stroke-drug-can-fail/?wt.mc=SA_Twitter-Share
 Twenty years ago stroke doctors celebrated the arrival of a powerful new weapon: the clot-clearing drug tPA. It was hailed as a lifesaver and has proved to be one for hundreds of thousands of patients since. TPA was the first and is still the only medicine approved by the U.S. Food and Drug Administration for treating strokes caused by clots that block blood flow to the brain. But like so many medical marvels, tPA (which stands for tissue plasminogen activator) has turned out to have serious limitations. It needs to be administered within three hours of symptom onset, does not last long in the body before it loses effectiveness, can cause uncontrolled bleeding and often fails to break up large clots.
For many of the nearly 800,000 Americans who every year suffer ischemic strokes, as the brain blockages are called, these shortcomings can be deadly. Nearly 130,000 die. Sadly, there have been no good alternatives to tPA since it debuted.
Recently doctors and scientists have broken this long-standing clinical stalemate with new tools to put a dent in those grim numbers. One innovation, a tiny wire device called a stent retriever, can be snaked up into the blood vessels leading to the brain to pull out large clots. “It's the first proven, effective treatment for acute stroke in a generation,” says Jeffrey Saver, director of the Stroke Center at the University of California, Los Angeles. Approved by the FDA in 2012, the stent retriever got a boost this year when the journal Stroke reported data showing many more patients treated with a retriever resumed normal life than did patients who received tPA. (The retriever manufacturer, Medtronic, provided support for the studies. Neurologist Bruce Campbell of the Royal Melbourne Hospital in Australia, who co-led the analysis, notes that Stroke has “strict independent-peer-review processes” to guard against bias.) Researchers are also developing better clot-detection scans, as well as a technique involving magnetism that guides tPA directly to the problem. This method could help eliminate dangerous obstructions elsewhere in the body, as well as in the brain.

Big Clots, Big Trouble

Of all of tPA's drawbacks, the most troublesome is its inadequacy against big clots, which can block large blood vessels at the base of the brain; they cause about 25 to 30 percent of all strokes. Although it works well against smaller clots in narrower vessels, a safe dose of the drug—which is delivered intravenously—often does not last long enough in the bloodstream to dissolve the big clots, and increasing the dose raises the risk of bleeding. “All you need to see is one intracranial bleed from tPA, and you realize you've got to pause before you give that medication,” says Thomas Maldonado, a clot specialist at New York University's Langone Medical Center.
This is where the stent retriever has an advantage. It is a narrow tube that can be threaded up from the femoral artery in the leg to the site of the clot. Then wire mesh on the end of the retriever, which expands like an accordion, is pushed into the clot. The mesh tendrils keep the clot from breaking apart in the brain—which could be deadly—and help separate it from blood vessel walls. The device is next pulled out of the body, and the clot comes with it. (In years past, doctors had tried a device with a corkscrew tip but found it was not as good at clearing the clot.)
Another advantage the device has over the drug is that the time window for the use of the stent retriever after symptoms arise is double that of tPA—six hours instead of three. The Stroke analysis found that blood flow in a vessel blocked by a large clot was successfully restored in 236 of 306 patients, or 77 percent, treated with the stent retriever. With tPA alone, the success rate was around 37 percent.
Like all surgical interventions, the stent retriever carries the risk of complications. The main one is bleeding, which is why patients with high blood pressure and the strained vessels that go with it may not be candidates for the procedure. “There's also a chance of the guide wire or some other manipulation of the device poking through the blood vessel during the procedure,” Saver says.
A much less common complication, Saver adds, is a piece of the clot breaking off as it is being pulled out, escaping into a new artery and causing a new stroke in a different area than the initial one. It happens in about 2 to 3 percent of cases, he says

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