A handful of centers around the U.S. are launching mobile stroke units with the hope of treating stroke patients faster, since "time is brain." , chair of the department of neurology at the University of Tennessee Health Science Center, and his colleagues run one such unit in Memphis. In this exclusive 乌鸦传媒 video, Alexandrov talks about the program, as well as the state of the science on mobile stroke units.
A transcript of his remarks follows.
In Memphis, we have a state-of-the-art mobile stroke unit with cutting-edge CT technology capable of CT angiography and the full 16-slice CT scan that we can perform in the field. The benefit of that technology to our community is that we can bring stroke expertise to the patient in the field.
This is unprecedented. We can be evaluating stroke patients right there with paramedics and quickly decide if it looks like a stroke or not, and then secondly, without any delays, we can perform a head CT in just about four minutes in the field. We can quickly triage the patient as to whether they need the clot-busting medicine tPA. Do they have large vessel lesions, and if such, we can bypass the nearest hospital or even primary stroke centers and go directly to comprehensive stroke centers right from the field, removing all the guesswork if this patient has large vessel lesion. This is currently accomplished by some kind of clinical scales based on the patient's symptoms rather than hard radiological findings from CT angiography.
This is early patient access to stroke expertise, to state-of-the-art imaging, and faster initiation of therapy and delivery to the appropriate institution. So far our unit is actually the first one to be stationed and integrated fully with the Memphis Fire Department. We're stationed at the actual fire station with eight shifts, like paramedics and fire fighters have. We're activated by 9-1-1. We respond to the majority of the Memphis area because driving distances are quite accessible here, and we're able to deliver across competing institutions.
In some cases, we even skip the emergency room and bring patients directly to cath labs so mechanical thrombectomy can be performed for certain types of stroke. Memphis Mobile Stroke Unit joined a group of centers worldwide that pioneered this technology. It started in Berlin and Hamburg in Germany, and the first center in United States was in Houston, followed by the Cleveland Clinic, Denver, Toledo, and now us. There are also units now in operation in New York City, Phoenix, and soon Los Angeles.
This is the group of centers that pioneer this technology and so far the available evidence shows as following. For the first time, we have a consistent opportunity to treat a larger proportion of stroke patients within the first 60 minutes from symptom onset. Time is brain, and before this technology was available, very few patients were ever treated under 60 minutes just because it takes hospitals up to 60 minutes to work up those patients and give tPA after their arrival to the hospital.
The fastest treatment time from arrival to completion of the CT scan and initiation of tPA now in Memphis is eight minutes. So instead of 60 minutes in the hospital, eight minutes in the field. If you combine that short arrival-to-treatment time, quick activation, and picking up the patients in the field, a larger proportion of patients can receive tPA within the first 60 minutes, and that has been shown in prior studies.
So it is feasible to treat very early. Studies also show it is feasible to treat faster on mobile stroke units than in the hospitals. It can be done safely. We know that safety is not compromised because experts are evaluating patients in the field and delivering tPA therapy very similarly to how they do in their own emergency rooms.
Right now, we need evidence and we participate in a multi-center study called Best MSU, which would answer the question of whether this earlier, faster, and safer treatment results in better functional outcomes in 90 days. We're looking forward to the results. They will be done shortly.
The future of stroke treatment is in the field, as soon as possible, because time is brain. Right now our capability to equip every ambulance out there that could potentially pick up stroke patients is restricted by the weight, size, and cost of the CT scan, the need for having an x-ray tech, and expertise to read those images and so forth. But imagine in the future if we have a small, portable, inexpensive device that can quickly say stroke or no stroke. Or ideally, not only it's a stroke, but it's also hemorrhagic or ischemic stroke. Then you can have teleneurology, teleradiology capability to look at that. Then paramedics will be calling from the field and saying, "I've got a stroke patient. Which medicine you would like me to give?"
In the future, there is no reason why paramedics should not be able to treat those folks in the field with remote access to stroke expertise. But that's in the future when we have those technologies available to us. Until then, it's a CT scan and we're trying to make it sustainable even with this technology.