ARTICLE IN BRIEF
Results from the first 100 patients seen by the Cleveland Clinic's stroke ambulance, which is equipped with telemedicine technology, showed that the time from “door” to intravenous thrombolysis was 26 minutes faster for stroke patients evaluated and treated on the mobile unit compared with control patients brought to the emergency department.
A mobile stroke treatment unit that utilizes telemedicine might be a good alternative to having a neurologist on board, according to a report published in the December 7 online edition of JAMA Neurology.
Results from the first 100 patients seen by the Cleveland Clinic's stroke ambulance — which is equipped with a CT scanner, portable laboratory, and telemedicine capabilities to connect with a vascular neurologist — showed that the time from “door” to intravenous thrombolysis was 26 minutes faster for stroke patients evaluated and treated on the mobile unit compared with control patients brought to the emergency department. The study also indicated that the telemedicine technology on board was almost always reliable.
Indeed, as stroke care is increasingly focused on getting clot-busting therapies to patients as quickly as possible, more attention is being paid to optimizing the prehospital phase of care through better triage in the field and organization of stroke services within a given community.
“Studies exploring prehospital delays in stroke care have revealed that only 15 percent to 60 percent of patients having a stroke are able to reach the hospital within three hours of symptom onset,” the study authors noted.
The few other mobile stroke treatment units (MSTUs) in operation in Germany and Houston utilize an on-board neurologist on their response team. While early results from those programs are favorable, one drawback is that it is expensive and not necessarily practical to have a neurologist drive around with the ambulance crew. In some locations, neurologists, especially vascular neurologists, are in short supply.
“An MSTU using telemedicine is feasible, with a low rate of technical failure, and may provide an avenue for reducing the high cost of such systems,” concluded the report from the Cleveland Clinic. The report only evaluated response time and technology reliability; it did not consider whether patient outcomes were better with the MSTU or if the telemedicine approach was cost-effective.
STUDY METHODOLOGY, FINDINGS
The study, conducted prospectively from July 18 to November 1, 2014, included the first 100 residents of Cleveland who had an acute onset of stroke-like symptoms during a 12-hour period and were evaluated by the MSTU. A vascular neurologist evaluated the patients via telemedicine and a neuroradiologist remotely assessed brain images taken with a CT unit in the ambulance. If indicated, tissue plasminogen activator (tPA) was started on the spot.
Researchers compared those 100 patients to 56 patients of similar age and stroke severity who were brought as usual to the emergency department (ED). Process times were measured from the time the patients entered the door of the MSTU or ED, and any problems encountered during evaluations were recorded.
Among the findings:
- The median time from door to CT completion was 13 minutes for MSTU patients, compared to 18 minutes for ED patients.
- The median time from door to intravenous thrombolysis (IV tPA) was 32 minutes for MSTU patients, compared to 58 minutes for the controls.
- The quickest time from door to IV tPA was 11 minutes.
- Times to CT interpretation did not differ significantly between the groups.
- The median duration of a telemedicine evaluation was 20 minutes.
- CT was completed in all patients but one. That patient required advanced cardiac support.
- One connection failure occurred due to crew error, and the patient was taken to the nearest ED.
- There were six telemedicine disconnections, none of which lasted longer than 60 seconds or affected clinical care.
“Our data demonstrated that the evaluation and treatment were not only comparable to ED times but also shorter in terms of CT, laboratory processing, and thrombolytic administration,” the researchers reported. “Intravenous thrombolysis was successfully administered to 48.5 percent (16 of 33) patients with suspected stroke and was delivered quickly in the MSTU.”
An editorial accompanying the study said that while MTSUs using telemedicine would seem like the next logical step in improving stroke care, “the unequivocal proof of better outcomes after treatment is required.”
The Cleveland mobile stroke unit has now cared for more than 400 patients and has extended its reach beyond the city into the suburbs, Ken Uchino, MD, a study coauthor and research director of the Cerebrovascular Center at the Cleveland Clinic, told Neurology Today. He said there have been improvements in the quality of CT scans and the way evaluations are conducted since the unit was launched. Feedback from patients and families is positive, he said.
The next step is to try to collect data on clinical outcomes, Dr. Uchino said, though he noted that “since patients are distributed throughout different hospital systems, that has presented some challenges.”
“This report demonstrated that the approach is practical and that the patient can be treated in a rapid manner by a mobile telemedicine encounter,” said Jeffrey L. Saver, MD, FAAN, a professor of neurology at the David Geffen School of Medicine at the University of California, Los Angeles (UCLA) and director of the UCLA Comprehensive Stroke Center, who was not involved with the study. But two important questions remain, he said: Are patient outcomes are improved? And if so, are they substantial enough to justify the costs?
Plus, a mobile stroke unit might not work well in all regions because of geographic factors or the particular makeup of hospitals and stroke services in a community, Dr. Saver said. Stroke ambulances are likely to work best in high-density urban areas, he said, adding that discussions with donors are underway to potentially start a program at UCLA.
Telemedicine has been shown to be useful for in-hospital stroke care, allowing for expert evaluation of stroke patients by a neurologist offsite, he noted. But whether the same concept could work in the field is not clear.
An evaluation of clinical outcomes and cost-effectiveness is being done in Houston, where a mobile stroke unit with a neurologist on board was launched last year as a research project led by James C. Grotta, MD, FAAN, director of stroke research at Memorial Hermann-Texas Medical Center. He personally staffs the stroke ambulance.
Dr. Grotta, formerly chair of neurology at the University of Texas Health Science Center at Houston, said telemedicine is “a valuable way to spread expertise more widely,” but additional research is needed to determine whether telemedicine evaluations are as accurate as in-person ones and whether the expense of a mobile stroke ambulance translates into lower health care bills.
It will be important to answer the question of whether this strategy is cost-effective in the long run, he said, noting that insurers will want proof that mobile stroke care offers an advantage over a traditional emergency response team.
Robert J. Adams, MD, a professor of neurology at the Medical University of South Carolina, said that mobile stroke units have now been tested enough that they will likely be part of the “stroke treatment ecosystem” in the future, but they may not make sense for every community depending on its density and the configuration of stroke hospitals. Another factor in the equation is the growing use of “stent-retriever” thrombectomy along with tPA for certain patients with acute ischemic stroke. That technology is only available at comprehensive stroke centers.
Dr. Adams said the first priority should be organizing an emergency response system that is focused on getting stroke patients to the best hospital for their needs, something that “requires no capital investment. After that I'd consider the question of whether a mobile stroke unit would be valuable.”
DIFFERENT MODELS OF CARE
In Pittsburgh, a pilot project is underway that utilizes tablets to connect several emergency medical services providers with a medic command doctor who conducts a stroke evaluation by telemedicine using the Rapid Arterial Occlusion Evaluation (RACE) scale, an assessment tool based on the NIH Stroke Scale that evaluates stroke severity and identifies patients with acute stroke with large artery occlusion in a prehospital setting. At the same time, other ambulance services will be trained in performing the RACE scale without the support of telemedicine. The ability of these approaches to identify patients for endovascular therapy will be compared.
“The idea is to reliably detect patients with large vessel occlusions who might benefit from direct transport to a comprehensive stroke center where endovascular therapy is available,” said Lawrence R. Wechsler, MD, FAAN, the Henry B. Higman professor of neurology and chairman of neurology at the University of Pittsburgh.
No matter which model proves best, the goal must be to “get the right patient to the right place for the right treatment in the shortest period of time,” Dr. Wechsler said.
EXPERTS: ON THE EFFECTIVENESS OF A MOBILE STROKE UNIT