News Release

Studies: delay in seeking stroke treatment can lead to death, permanent impairment

Peer-Reviewed Publication

University of North Carolina at Chapel Hill

CHAPEL HILL -- People who think they or someone else is suffering a stroke need to call 911 to summon emergency medical service (EMS) immediately and not wait for any reason, according to two new University of North Carolina at Chapel Hill studies. That's the most effective way to take advantage of a new clot-busting drug known as tPA and possibly prevent death or permanent impairment.

The related studies, conducted at the UNC-CH schools of public health and medicine, focused on why stroke treatment often is delayed. Both appear in the November issue of Stroke, a publication of the American Heart Association.

One, titled "Second Delay in Accessing Stroke Healthcare (DASH 11) Study," looked at how patients and witnesses reacted to stroke symptoms and tracked 617 patients arriving at hospital emergency rooms in Denver, Chapel Hill, N.C. and Greenville, N.C.

Patients who used EMS had a median pre-hospital delay of 2.85 hours, compared to 4.03 hours for those who didn't use EMS, said doctoral student Emily Schroeder and her mentor, Dr. Wayne D. Rosamond, assistant professor of epidemiology. But even the 2.85-hour median elapsed time for patients using EMS is far too slow.

"It can take an hour or more to complete and interpret necessary tests like a CT scan, which have to be done before thrombolytic (clot-dissolving) therapy can be given," Schroeder said. "The time a patient takes deciding to seek care is the biggest portion of the time between onset of symptoms and treatment. Once EMS is alerted, things can happen quickly, but people don't call 911 unless they perceive their symptoms to be urgent."

Dr. Dexter L. Morris, vice chair of emergency medicine at UNC-CH, led the second study, which involved monitoring 1,207 patients diagnosed with stroke or "mini-strokes" at 48 hospital emergency rooms nationwide.

"There's a limited window of opportunity of about three hours after the onset of stroke symptoms in which the patient's outcome can be altered by thrombolytic therapy," Morris said. "This treatment appears to give a patient a 30 percent better chance of having minimal or no stroke-related disability."

In that study, the Genentech Stroke Presentation Survey, the median delay time before treatment was four hours and in some cases, treatment was not begun for more than eight hours.

Delays were shortened when someone other than the patient noticed their symptoms, which can include headache, dizziness, confusion, loss of speech, vision impairment, numbness and paralysis, Morris said. The most significant factor in cutting time before treatment was calling EMS quickly.

Time-consuming tests in emergency rooms are essential because the drug tPA can only help patients with ischemic stroke, the kind caused by interrupted blood flow to the brain. The other major stroke type, subarachnoid hemorrhage, involves bleeding inside the skull and could be made much worse with tPA therapy.

Morris recommended that hospitals and EMS personnel improve training and establish standard procedures -- and in larger hospitals special teams -- for processing possible stroke patients as quickly as possible.

"This work underscores the need for a multi-faceted approach to acute stroke care involving public health agencies, EMS personnel, emergency room physicians and nurses and neurologists," Schroeder said. "Clearly, one group working independently won't be able to deliver thrombolytic therapy in time to help all the acute stroke patients who need it.

Others involved in the studies include Drs. Kelly R. Evenson, Albert R. Hinn, Kenneth Madden, Carol Schultz and Scott Hamilton.

###

Note: Schroeder can be reached at (919) 966-1967 or eschroeder@email.unc.edu, Rosamond at 966-7419 or wayne_rosamond@unc.edu and Morris at 966-5033 or dmorris@med.unc.edu.

School of Public Health contact: Lisa Katz, (919) 966-7467. News Services contact: David Williamson, (919) 962-8596.


Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.