Quality of care is improved significantly when emergency department (ED) physicians are allowed to deliver clot-busting drugs to appropriate stroke patients without waiting for dedicated stroke teams, according to a new study.
Current wisdom calls for judicial use of special thrombolytic drugs called tissue plasminogen activators (tPA) that can break up a clot and cut the risk of brain damage, with many hospitals restricting their use to special teams trained to use them. That may not be necessary, according to findings from a four-hospital retrospective study of tPA treatment for ischemic stroke led by researchers from the University of Michigan (U-M) Health System in Ann Arbor. The study results were presented recently at the annual meeting of the Society for Academic Emergency Medicine in St. Louis.
Phillip Scott, MD, FAAEM, director of the UMHS Emergency Stroke Team and assistant professor in the U-M Department of Emergency Medicine, was the lead author. He says some patients who could benefit from tPA have to wait too long before the special team arrives. "Despite all the proof that tPA works, emergency physicians have hesitated to use it because of concerns about achieving results similar to centers with specialized stroke teams, and the perceived liability they might face if it causes the patient to hemorrhage. But what we have shown is that with diligent use of stroke treatment protocols, and specialty neurologist consultation as needed, the complication rate for patients treated by an ED team is the same as for those treated by specialized stroke teams."
The study looked at data from 140 patients treated with tPA from 1996 to 2001 by emergency physicians at community, university, and urban teaching hospitals, and a community nonteaching hospital. All the hospitals used acute stroke treatment guidelines, and patients were treated by board-certified or board-eligible emergency physicians. The rate of serious bleeding complications (intracranial hemorrhage) in patients treated in the four EDs was 7%: the same as in previous studies of tPA use by dedicated stroke teams. That kind of bleeding is a known risk of tPA use, but despite the risk, treatment within three hours of symptom onset improved clinical outcomes at three months.
The U-M study looked at the records of the 140 patients to see how they fared before and after tPA treatment by what Scott calls a "distributed stroke team." Forty-four percent of the patients entered the ED with mild to moderately severe neurological impairment, as measured by the National Institutes of Health stroke scale, and another 32% had severe impairment.
The tPA did its job in most cases; 59% of the patients left the ED in better condition than they went in, and an additional 9% left the ED feeling like their normal selves. This positive result is probably due to the fact that the ED teams treated the patients with proper speed, giving tPA within an hour and a half of the patient’s arrival at the ED, on average.
Most patients were treated within the recommended three-hour window from stroke onset; 22 patients were treated despite having gone past the three-hour mark, though the median number of minutes over the deadline was 12. Some patients asked for tPA despite being over the time limit.
Even if they don’t have a stroke team at their hospital, ED physicians don’t have to go it alone when making the decision about whether a patient is a candidate for tPA, Scott says.
"In 65% of the patients in our study, the ED physician consulted with a neurologist before giving tPA, and half of those consultations took place over the phone. Making the call about stroke diagnosis and tPA treatment can be tough, but with the proper support, an ED physician can do it with confidence."