Prehospital Alerts for Stroke Patients

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Prehospital stroke alerts by emergency medical services personnel can shorten the time to effective treatment with "clot-busting" drugs for patients who have had a stroke, according to a report in the March issue of Neurosurgery, official journal of the Congress of Neurological Surgeons.  

A release from the publisher reports that Dr. Mandy J. Binning and colleagues at the Capital Institute for Neurosciences in Trenton and Pennington NJ. implemented a prehospital stroke alert (PHSA) protocol in a specialized neurological emergency department (ED) setting. The PHSA approach allows patients with probable stroke to bypass the ED and go for immediate computed tomography (CT) scanning, saving valuable minutes

The PHSA system was introduced at Capital Health's two neurological EDs to facilitate emergency treatment with tissue plasminogen activator (tPA). Intravenous tPA can dissolve the clot that's causing the stroke. However, to be effective, treatment must be started within 4.5 hours after initial stroke symptoms. Ideally, the "door-to-needle" time—from arrival at the hospital to the start of tPA treatment—should be less than one hour.

In the PHSA approach, specialists at the CIN gave EMS personnel special training in identifying stroke patients. After training, the EMS personnel could send a prenotification to the hospital, letting the ED team know that a patient with possible stroke was on the way.

After issuing a PHSA, the EMS personnel brought the patient directly to the CT suite, bypassing the usual ED routines. They were met by the neurological emergency team, which performed a quick assessment and CT scan of the brain. If stroke was confirmed in the appropriate time frame, tPA treatment was started immediately.

The new study reports on 141 patients with prehospital stroke alerts who were stable enough to bypass the ED and go directly to CT. The EMS personnel made an accurate assessment of stroke in two thirds of patients, and correctly identified patients with neurological conditions nearly 90 percent of the time.

On average, CT scans were performed about 12 minutes after the patient arrived at the hospital—compared to 35 minutes before the PHSA system was introduced.

The median door-to-needle time was 57 minutes, compared to 99 minutes before the PHSA system. The overall percentage of stroke patients receiving tPA was 18 percent, compared to an average of five percent over the previous three years.

Despite the documented benefits of clot-dissolving drugs for patients with stroke and recommendations for rapid treatment, only a small percentage of stroke patients actually receive tPA. Hospital prenotification by EMS providers has been recommended to speed ED evaluation of patients with possible stroke. The new study shows that combining PHSAs with treatment at a specialized neurological ED can shorten the time to CT scanning and, when appropriate, tPA treatment in patients with stroke.

Dr. Binning and colleagues note that door-to-needle times have continued to decrease since the introduction of the PHSA protocol. They also report that they're seeing increased numbers of stroke patients—likely because EMS personnel are preferentially transporting patients with probable stroke to the neurological EDs, where they can receive specialized stroke care.

The improvements in door-to-CT and door-to-needle times "suggest that we are triaging and treating patients with acute neurological and neurosurgical emergencies more quickly," Dr. Binning and coauthors write. They are planning further studies to compare clinical outcomes in stroke patients treated before and after introduction of the PHSA protocol.