Mobile stroke units decrease time to imaging, treatment
A telemedicine-enabled mobile stroke ambulance with a CT scanner helped patients receive thrombolysis faster than with a traditional ambulance, according to findings published in Neurology.
“Each link in the prehospital stroke rescue chain matters, and mobile stroke units appear to have the greatest potential in accelerating the process to IV thrombolysis and delivery to definitive care,” Muhammad S. Hussain, MD, of the cerebrovascular center at the Cleveland Clinic, and colleagues wrote.
Researchers analyzed data from the first 100 patients (median age, 62 years; 54% women) who were transported to the hospital by the telemedicine-enabled stroke ambulance in Cleveland from 8 a.m. to 8 p.m., the time when most stroke dispatches occur, July 18 to Nov. 1, 2014. The data were compared with a control group (n = 53; median age, 63 years; 30% women) with patients who had a stroke alert and were transported to Cleveland Clinic by emergency medical services in 2014 during the same time frame.
Both the mobile stroke ambulance and an EMS squad were called to all potential stroke calls. Once it was determined that the patient was experiencing a stroke, the patient then received care from the telemedicine-enabled mobile stroke ambulance.
Features of mobile unit
A registered nurse, CT technologist, emergency medical technician and paramedic were on board the ambulance while a vascular neurologist and neuroradiologist received images, video and lab results at the hospital over the network. The vascular neurologist instructed the team aboard the ambulance while they transported the patient to the hospital.
In patients treated by the telemedicine-enabled mobile stroke ambulance, the median NIH Stroke Scale score was 6 (interquartile range [IQR], 2-12) vs. 7 in the control group (IQR, 3-12; P = .679). Of the 100 patients who were transported to the hospital by the mobile stroke ambulance, 33 were diagnosed with probable acute ischemic stroke, 30 patients had possible acute ischemic stroke and four patients experienced transient ischemic attack.
From dispatch call time, the telemedicine-enabled mobile stroke ambulance took an average of 12 minutes (IQR, 8-14) to arrive to its location and 20 minutes from the call time to when the patient entered the mobile stroke ambulance’s door. The median time a patient was under the care of the mobile stroke ambulance was 86 minutes (IQR, 78-94).
CT scans were completed in the mobile stroke ambulance in 33 minutes on average from the time of alarm (IQR, 29-41) and read in 44 minutes (IQR, 39-52). These times were significantly shorter compared with the control group. The median time was shorter by 23 minutes for CT completion (P < .0001), and shorter by 20 minutes for a CT reading (P < .0001).
Sixteen of the patients treated in the telemedicine-enabled mobile stroke ambulance were given thrombolysis, which made up 48% of the patients diagnosed with probable stroke. The treatment was administered to patients in the mobile stroke ambulance 38.5 minutes sooner after the alarm (median, 55.5 minutes; IQR, 24-47) than the control group (median, 94 minutes; IQR, 78-104; P < .0001). From symptom onset, patients treated in the mobile stroke ambulance were administered thrombolysis 25.5 minutes sooner (median, 97 minutes; IQR, 61-144) than the control group (median, 122.5 minutes; IQR, 110-176; P = .0485).
One-quarter of patients received thrombolysis within an hour of symptom onset, whereas no patients in the control group received it within that time frame.
“The sooner someone is treated for stroke, the better chance they have for survival and an improved recover,” Hussain said in a press release. “Telemedicine makes it possible for a neurologist to see a stroke patient, and possibly treat them, before they even arrive at the hospital.”
In a related editorial, Andrew M. Southerland, MD, MSc, assistant professor of neurology at the University of Virginia Heath System, and Ethan S. Brandler, MD, MPH, of the department of emergency medicine at SUNY Stony Brook Medicine, New York, wrote, “In the meantime, ongoing efforts are needed to streamline [mobile stroke unit] cost and efficiency before achieving road-readiness for widespread health system development.” – by Darlene Dobkowski
Disclosure: The researchers and Southerland report no relevant financial disclosures. Brandler reports receiving research support from Janssen Research and Development.