Should Stroke Patients Be Transported Directly to a Comprehensive Stroke Center?
Why Two Stroke Experts Beg to Differ
By Ed Susman
June 6, 2019
Article In Brief
Should ambulances bypass primary stroke centers for comprehensive stroke centers? One specialist argues that the availability of thrombectomy is reason to go to a comprehensive stroke center, while another finds that in urban areas, in particular, the time to travel in traffic can wipe out any potential gains.
PHILADELPHIA—If you want to get the best care for stroke patients, don't stop at the nearby primary stroke center, but continue on directly to a comprehensive center where thrombectomy is routinely delivered to save patients' lives and well-being.
At least, that is the position of Lee H. Schwamm, MD, professor of neurology at Harvard Medical School and director of the Comprehensive Stroke Center and Center for Telehealth at Massachusetts General Hospital in Boston, who argued in favor of the proposition: Should ambulances bypass primary stroke centers for comprehensive stroke centers?
“If you are a primary stroke center and you can't give tPA fast, and you can't get the patient in and out of the door fast, and you can't do imaging to look for proximal occlusions, you shouldn't be in this fight, because it is not fair to the patients,” he exhorted the audience at the AAN Annual Meeting here.
But the throng of neurologists attending the Controversies in Neurology plenary session wasn't buying it.
Instead, by a 62 percent to 38 percent margin, as recorded using an interactive AAN app on their cell phones, they sided with the “con” position, argued by Johanna Fifi, MD, associate professor of neurology, neurosurgery and radiology at the Icahn School of Medicine at Mount Sinai School of Medicine, and director of the Endovascular Stroke Program at the Mount Sinai Health System, in New York City.
“If all the patients who needed this treatment could be identified in the field and delivered to a comprehensive stroke center it would make sense to bypass the primary centers, but there are many reasons this is not possible,” Dr. Fifi said.
“The geographical distribution of these centers is not amenable to this in many areas of the country,” she said. “Large vessel occlusions can't be accurately identified in the field and the false identification may lead to compromise of overall stroke care. Time to thrombectomy is very important but so is time to thrombolysis.”
Dr. Schwamm anchored his argument by focusing on the benefit of thrombectomy, the procedure with proven efficacy in patients with large vessel occlusions. “If every stroke center could do what this one-hour artery clearance procedure could do, we would not have this debate,” he said. “We know that thrombectomy is highly efficacious and is one of the most efficacious treatments we have to offer but we know that it is not always equitably accessed by individuals in our community. We know that the effect is highly time dependent, and while the numbers suggest that it is only 12 to 20 percent of all ischemic strokes, they carry a disproportionate burden of death and disability.”
“Our thinking has been linear in that we think of all these centers of lower capability transferring patients to a thrombectomy-capable center when appropriate patients are identified,” Dr. Schwamm said. But that assumes a trip to a primary stroke center works in an ideal fashion.
He suggested that the general thinking is that you can get a stroke patients through work-up and off to a thrombectomy center within 45 minutes, but “in reality it is far different. The wrong first choice can be very costly because many times the nearest hospital is in the opposite direction from a comprehensive center.”
Dr. Schwamm suggested that part of the resistance to going to the comprehensive stroke center may be biased by health care finances. The incentive to bypass the closest stroke center for a comprehensive hospital is influenced by market factors, Dr. Schwamm said, and part of that is due to the desire of hospitals to retain patients for financial reimbursement.
And he identified other problems with the primary stroke centers. Among them, huge delays occur when patients enter an emergency department with long door-in, door-out times, primary stroke centers administer intravenous alteplase less rapidly and less often than comprehensive stroke centers, and many cases that arrive at the primary stroke centers end up needing to be transferred to comprehensive stroke centers eventually—especially patients with large strokes, intracerebral hemorrhage and strokes with complex etiology.
“Going to the primary stroke center first poses the greatest risk of harm to those who would benefit the most,” Dr. Schwamm said.
He added that while telemedicine can help transmit knowledge from one facility to another, “You can't make procedure expertise available on-site everywhere. More than half of all U.S. stroke admissions are never seen by a neurologist. There is little or no support or public health strategy for interfacility transport beyond the emergency phase of care.”
His solution? All patients suspected of stroke should undergo emergency medical service screening and severity score. All patients potentially eligible for acute reperfusion therapy go immediately to a pre-defined comprehensive stroke center for intravenous thrombolysis and/or endovascular therapy. This concentrates reperfusion therapy at high volume centers and leads to ideal performance. Once evaluated by the comprehensive stroke center, low complexity patients can be returned to their “home” hospital by interfacility emergency medical services.
All that would be fine, Dr. Fifi said in rebuttal, except for a few problems: Getting across a city such as New York during rush hour to reach a comprehensive stroke center can take so long it wipes out the advantage of expertise in performing thrombectomy or intravenous tissue plasminogen activator (tPA). She showed that most comprehensive stroke centers are clustered in the heart of cities, which means getting patients to the center even with ambulance sirens blaring is problematic.
“This isn't a debate about the efficacy of treatment for large vessel occlusion,” she said. “We all know thrombectomy is important, and it is not a debate about time because we know that the quicker you open the vessel, the better patients do.”
Then there is the problem of deciding which patients should go to the comprehensive stroke center by emergency medical services. “Screening in the field is very challenging,” Dr. Fifi said. Stroke calls occur in about 1.25 percent of EMS calls in New York City; the best test for identifying large vessel occlusions is CT angiography. But there are few mobile units that can perform the test in the field; they are impractical in cities like New York and are too expensive to create a fleet of such vehicles, she said.
She also was concerned that a policy that took stroke patients directly to the comprehensive stroke center could backfire by overloading the comprehensive centers with patients who didn't need to be there, taking up valuable resources, hospital beds—and even ambulances.
Dr. Fifi acknowledged that primary stroke centers do need to get better, too, in caring for stroke patients. She also suggested that you could fly the specialist into primary centers, and there might be a role for robotic thrombectomy.
Dr. Schwamm disclosed relationships with Penumbra, Medtronic, Genentech, LifeImage, and Boehringer Ingelheim. Dr. Fifi disclosed relationships with Synchron, Endostream, Imperative Care, Cerebrotech, Stryker, Penumbra, and Microvention.