May is Stroke Awareness Month and an ideal time to discuss some of the innovative technology first responders use when dispatched to a person presenting with stroke symptoms.
Each year strokes take about 140,000 lives in the U.S. according the Centers for Disease Control and Prevention. A stroke can occur at any age, but 75% of strokes happen to people 65 and older, according to data from the CDC. Among children, 17% to 24% with sickle cell disease experience strokes.
How one mobile stroke unit improves stroke care
Eugene Lin, MD, is a neuroendovascular surgeon and vascular neurologist at Mercy Health St. Vincent Hospital in Toledo, Ohio. He also serves as medical director for the Mercy Health Mobile Stroke Unit, working closely with a special group of EMS staff dispatched to treat people suspected of stroke symptoms.
The team is part of the mobile stroke unit equipped with CT scanning equipment capable of detecting whether a patient is suffering from an ischemic or hemorrhagic stroke, Lin said.
“We launched a mobile stroke unit three years ago,” he said. “We have a lot of contact with Lucas County EMS, which coordinates 400 EMS members along with the Toledo Fire Department.”
Lin’s team works closely with the EMS and fire department during its quarterly education sessions to discuss any protocol changes related to the mobile stroke unit operated by Lucas County EMS. The mobile stroke unit runs 24/7 with a dedicated EMS team. One registered nurse, one paramedic and a technologist who runs the CT machine are all aboard the ambulance, Lin said. All staff are certified by the National Institutes of Health Stroke Scales (NIHSS).
From the hospital, by Lin and Osama O. Zaidat, MD provide teleneurology — both interventional and vascular neurologists who guide the EMS team through treatment protocols.
Stroke scales detect impairment level
Stroke scales help healthcare providers determine an appropriate course of treatment and help ascertain potential outcomes for a stroke patient.
Patients are scored based on their level of consciousness and how well they perform specific tasks, like squeezing your hand or blinking an eye. NIHSS use 11 elements to determine the patient’s score.
“FAST is one scale used to diagnose strokes,” Lin said. “If they do have stroke symptoms, EMS can then use the RACE scale, pre-hospital identification of large vessel occlusion stroke.”
FAST stands for:
- Face — Are there signs of facial drooping?
- Arms — After a patient raises his or her arms, is one arm more elevated?
- Speech — Is it slurred?
- Time — Call 911 if any symptom is present.
RACE is an acronym used to detect pre-hospital large vessel occlusion stroke.
- It stands for Rapid Arterial oCclusion Evaluation
Mobile stroke units have extra medication on board
The inside of the mobile stroke unit looks the same as any other ambulance — except for a CT machine. These first responders also have access to a more robust medicine cabinet, compared to a regular ambulance.
“Medications we do have that are unique include Nicardipine, for blood pressure control,” Lin said. “Kcentra to reverse Coumadin. Mannitol for increased cranial pressure and Keppra, if they have a seizure.”
With ischemic strokes, Lin said the patient would need IV-tPA medication. Patients can only receive this type of medicine if it has been determined they are having an ischemic stroke.
Having access to mobile stroke units helps first responders make that determination, along with a physician’s help.
“Any injury to the brain can cause stroke symptoms, but only a head CT scan can distinguish whether it’s ischemia or hemorrhage in the brain,” Lin said. “If stroke patients have an ischemic stroke, they still may not qualify for IV-tPA medication if they are outside the 4.5-hour window.”
Benefits of mobile stroke units
Every minute matters when treating a person with stroke symptoms.
“The benefit of a mobile stroke unit — it facilitates IV-tPA more quickly because the CT imaging is available and the IV-tPA can be administered more quickly,” Lin said. “It keeps patients in the window, so they are candidates for IV-tPA.”
Rural areas also benefit from mobile stroke units because people living outside of major metropolitan areas rarely have access to comprehensive stroke centers.
“We identify patients with large vessel occlusion and the mobile stroke unit allows us to bypass the local ED and go straight to a comprehensive stroke center,” Lin said. “It allows more accurate triaging of patients who are candidates for mechanical thrombectomy.”
In some cases, patients show immediate recovery once surgeons remove the blood clot, Lin said.
“We see this especially with large vessel occlusion where time is key to improving patient outcomes,” he said.
- 87% of strokes are ischemic, which means blood flow to the brain is blocked, according to the National Stroke Association.
- 15% of strokes are hemorrhagic, according to the National Stroke Association.
- Stroke is the fifth leading cause of death in the U.S, according to the National Stroke Association.
- About 140,000 people die from stokes each year in the U.S., according to the CDC.
- 1.9 million neurons die every minute blood flow does not reach the brain, according to Lin. This often affects speech, memory and movement.