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Focus on Prehospital Stroke Services:
The 3-letter abbreviation for tissue plasminogenactivator--tPA--gets most of the press, but effectivestroke care starts with 3 numbers: 911.Because the effectiveness of tPA therapy dependson administration within 3 hours of symptom onset,acute stroke outcomes for even the nation's most elitehospitals are limited by the number of patients whopresent within that window of time. That's why strokeresearchers increasingly are studying the prehospitalprocess of care in search of ways that emergency serviceprotocols can be fine-tuned--or, in some cases,overhauled--to give acute stroke patients the bestchance of a positive outcome."As we move toward establishing improved qualityof care, the logical extension is to improve quality ofcare in prehospital services," said Doojin Kim, MD, aclinical instructor of stroke neurology at the Universityof California at Los Angeles (UCLA), and one of morethan a dozen researchers who gave presentations onprehospital stroke care at either the International StrokeConference (ISC) in February or the American Academyof Neurology (AAN) annual meeting in April.ROOM FOR IMPROVEMENTDespite efforts by the American Heart Association andthe American Stroke Association to educate the publicabout stroke symptoms and the importance of immediatetherapy, research from the Yale School of Medicinein New Haven, Connecticut, suggests these effortshave done little to get patients to the hospitalmore quickly.1 Retrospective analysis by Judith H.Lichtman, PhD, MPH, and colleagues of patients admittedto 35 academic medical centers in 2001 and patientsadmitted to 32 academic centers in 2004 foundthat the percentage of those arriving within 2 hours ofsymptom onset remained the same: 32%. (The Yale researchersdid find, however, that mean door-to-CTtime in patients arriving within 2 hours decreasedfrom 0.9 hours in 2001 to 0.6 hours in 2004.)Even in patients who have no contraindications forthrombolysis and arrive at the hospital in enough timefor a CT scan to be performed within the 3-hour timeframe, thrombolytic therapy is not a given. Nancy K.Hills, PhD, an epidemiologist in the Department ofNeurology at the University of California at San Francisco(USCF), and S. Claiborne Johnston, MD, PhD, directorof the UCSF stroke service, found that thrombolyticswere administered at 11 California hospitalsin only 52% of 61 eligible patients who arrived within2.5 hours of symptom onset.2 Older age and later arrivaltime were predictive of nontreatment in thestudy, which was presented at the ISC.However, even those who do not receive thrombolytictherapy benefit from early arrival at the hospital,according to a study conducted jointly by Hills,Johnston, and other members of the California AcuteStroke Pilot Registry (CASPR) investigative team.3Of 812 ischemic stroke patients who arrived by ambulanceat 11 California hospitals, those who arrivedless than 2 hours from symptom onset had a shorterlength of stay than those who arrived later. The earlyarrivals also were more likely to be discharged to theirhome and to be ambulatory at discharge."Ninety-five percent of those who received recanalizationtherapy were in the under-2-hour group, butthat was a very small percentage of patients overall,"said Jeffrey L. Saver, MD, professor of neurology anddirector of the stroke center at UCLA, who presentedthe CASPR investigators' findings at the AAN meeting."However, many other patients likely received intravenousfluids, aspirin, and other aspects of supportivecare that can also make a difference in outcomes."TRANSPORT AUTHORITYIn the CASPR study, 57% of acute ischemic stroke patientsarrived at the hospital by ambulance; 57% ofthose arrived within 2 hours of symptom onset. Thissuggests that, at least to some extent, mode of transportis related to symptom-to-door time."Our findings help to confirm what I think manypeople suspected, that patients who call 911 tend to doso soon after onset," Saver said. "Patients who wait tosee if their symptoms go away or decide to be stoics about it are the patients who ultimately decide not tocall 911 but arrive by private vehicle."Bentley Bobrow, MD, medical director for emergencyservices in the Arizona Department of Health Servicesand an emergency physician at the Mayo ClinicHospital in Scottsdale, concurred with Saver's assessment."We have the same process of delivering thrombolysisto patients arriving by private vehicle as thosearriving via emergency medical services [EMS]. Unfortunately,our private-vehicle patients often arriveoutside the designated time window for IV tPA," saidBobrow, coauthor of a study detailing the extent ofEMS support for the Mayo Clinic.4 That study, presentedat the ISC, found that 81% of thrombolysedacute ischemic stroke patients arrived by ambulance.Research from Ohio State University (OSU) MedicalCenter, however, suggests that mode of transportmay be an independent determinant of the level ofcare a stroke patient receives. In a study of more than630,000 patients from the National Hospital AmbulatoryMedical Care Survey (a database maintained bythe CDC), Yousef M. Mohammad, MD, and colleaguesfound that those who arrived by ambulance wereevaluated more quickly, were more likely to undergoCT imaging, and were more likely to be admitted tothe hospital than walk-in patients (including those arrivingby car, bus, or taxi or on foot).5 Slightly morethan half (53%) of patients arrived by ambulance; 43%were walk-ins, and 4% came by public services (eg,police car) or their mode of transport was unknown."There are 2 disappointing conclusions from thestudy," said Mohammad, assistant professor of neurologyand director of the stroke fellowship programat OSU. "First, despite education of the public to considerstroke as an emergency, still only half call theEMS for transfer to the emergency department. Second,there is a difference in the management of strokepatients by the emergency department staff based onthe mode of arrival. The bottom line is that more educationon stroke is warranted for both the public andthe emergency department triage nurses and staff."LOCATION IS EVERYTHINGThe location and type of hospital at which stroke patientsare treated also may influence time from symptomonset to subsequent patient treatment. A study of18 suburban community hospitals in the greaterHouston area reported a median of 420 minutes fromsymptom onset to presentation.6 Those findings, presentedat the ISC, contrasted markedly with an earlierstudy of 6 more centrally located Houston hospitals, in which the median time from symptom onset to arrivalwas 95 minutes at the beginning of the study anddecreased to 89 minutes following a multifaceted educationalintervention.7"The suburban hospitals are less 'influenced' by thelevel of practice used by larger centers closer to downtown,and many of the stroke patients admitted tothese centers are managed by internists, not neurologists,"said lead researcher Anne W. Wojner-Alexandrov,PhD, CCRN, professor of clinical nursing at ArizonaState University.Hospital type also may influence the likelihood thata patient will receive thrombolytic therapy. At theMayo Clinic Hospital in Scottsdale, where stroke neurologistsare in-hospital a majority of the time and alwaysimmediately available, 100% of all eligible patientsreceived thrombolysis, Bobrow said. In theUCSF study, Hills and Johnston found that 72.2% ofeligible patients treated at academic hospitals receivedthrombolysis, compared with just 35.2% of those treatedat non-academic hospitals.ENLISTING EMSFinding a means of educating the public about strokethat results in more 911 calls remains a challenge, butstroke experts have found that increasing the involvementof EMS personnel in the stroke managementprocess has significantly improved the efficiency withwhich patients who do call 911 are treated once theyarrive at the hospital.One way in which emergency personnel are assistingis by notifying the destination hospital that a patientwith suspected acute ischemic stroke is en route. AbdulR. Abdullah, MD, a clinical research fellow in neurologyat Massachusetts General Hospital in Boston, andcolleagues found that prenotification significantly decreaseddoor-to-CT times and significantly increasedrates of thrombolysis.8 Door-to-CT time was 23% shorterin 44 cases of acute stroke in which the hospital receivedprenotification than in 74 cases in which prenotificationwas not given, and thrombolysis rates werenearly double in the prenotification group (41% vs21%). "In our study, we found out that EMS notificationwas effective regardless of whether the patient wascharacterized as 'possible stroke.' This highlights theimportance of notification per se," said Abdullah.The findings of Abdullah's team were consistentwith those of Perttu Lindsberg, MD, PhD, and colleaguesat the University of Helsinki in Finland, whotook a 3-fold approach to improving stroke care efficiency:moving the CT scanner into the emergency department (ED), assigning a dedicated nurse team tostroke triage, and implementing prenotification byEMS personnel.9 By 2004, incoming patients were beingentered into the CT call register an average of 15minutes before being admitted to the hospital, comparedwith 24 minutes after admission in 1999 (theprotocol changes were implemented between 2000and 2003). As a result, all of the 100 consecutive patientsstudied in 2004 were offered thrombolysis, comparedwith just 23 of the 100 consecutive patients studiedin 1999. Although symptom onset to arrival timedid not change significantly, symptom-to-needle timedecreased from 2 hours 44 minutes in 1999 to 2 hours5 minutes in 2004.TRIAGE IN TORONTOEven greater efficiencies and outcomes can be realizedwhen prenotification is combined with an en-route triagesystem in which suspected acute stroke patientsare directed to a designated stroke center. MassachusettsGeneral Hospital is one such center, as is theMayo Clinic Hospital in Scottsdale.In February 2005, the city of Toronto implementeda prehospital redirect program in which EMS personneltransporting suspected stroke patients are instructedto bypass local hospitals and go directly to one of 3regional stroke centers. At one of those regional strokecenters, Sunnybrook and Women's College Health SciencesCenter, tPA use tripled during the first 4 monthsin which this system was implemented, so that 34% ofischemic stroke patients arriving within 3 hours ofsymptom onset received thrombolysis.10The transition was not without its hurdles, with initialmistriage rates exacerbating overcrowding in anED already dealing with the effects of peak flu season,said Sandra E. Black, MD, chair of neurology at SunnybrookHealth Sciences Center (now a separate entityfrom the Women's College Hospital). "We did havepatients who were stroke-mimics, such as seizureswith postictal paralysis or other diagnoses," Blacksaid. "To counteract this, the base hospital introduceda patch system whereby the paramedics from anywherein Toronto phoned the emergency doctor andquickly reviewed the prompt card to make sure thepatient was appropriate for transport. This greatly reducedthe mistriage rate."In Los Angeles County, where prenotification occursin 32% of suspected stroke cases,11 Saver and colleagueshave further expanded the paramedic's role aspart of a study on the neuroprotective benefits of intravenousmagnesium sulfate within 2 hours of stroke symptom onset.12 In cases of suspected stroke, theparamedic not only notifies the hospital of the patient'sarrival but also puts the patient or family memberin cell-phone contact with an enrolling physicianat the hospital to discuss the magnesium sulfate study;the paramedic then obtains the necessary informedconsent form signatures and administers the neuroprotectantwhile en route to the hospital. The trial, describedat the ISC, is set to continue for 3 years.ACCEPT THE CHALLENGESaver and others are encouraged by the numbers ofstroke patients that are already being treated within aslittle as 2 hours of symptom onset. There is still morethat can be done."There are still many communities in our countrythat are resistant to adopting an emergency responseparadigm for stroke care," Wojner-Alexandrov said."There also may not be enough neurologists to attendto the emergency care needs of stroke victims throughoutour country. Unless internists, emergency physiciansand others are able to rise to this challenge, theremay continue to be problems with access to appropriateacute stroke care in many places. Telemedicinemay be one answer, but others must accept this challengewithin traditional practice communities if weare to make a difference in the disability and deathproduced by stroke." ■REFERENCES1. Lichtman JH, Allen NB, Cerese J, et al. Time from symptoms to presentation:are we doing better? Stroke. 2006;37:655.2. Hills NK, Johnston SC. Why are eligible thrombolysis candidates left untreated?Stroke. 2006;37:656.3. Saver JL, Starkman S, Hills N, et al. Hyperacute ambulance-arriving strokepatients: frequency and clinical characteristics. Neurology. 2006;66(suppl 2):A64.4. Spencer BR, Khan OM, Clark L, et al. Emergency medical services supportfor a primary stroke center. Stroke. 2006;37:740.5. Mohammad YM, Nasar A, Sheckman V, et al. Mode of arrival in patientspresenting to the emergency room with stroke in the United States. Stroke.2006;37:656.6. Wojner-Alexandrov AW, Martin S, Grotta JC, et al. Stroke emergency responseinitiative and outcomes utilization: Baseline community hospital performancedata--a need to get serious now! Stroke. 2006;37:657.7.Wojner-Alexandrov AW, Alexandrov AV, Rodriguez D, et al. Houston paramedicand emergency stroke treatment and outcomes study (HoPSTO).Stroke. 2005;36:1512-1518.8. Abdullah AR, Smith EE, Biddinger P, et al. Hospital notification by EMS inacute stroke is associated with shorter door-to-CT time and increased likelihoodof tPA administration. Stroke. 2006;37:635.9. Lindsberg P, Happola O, Kallela M, et al. How to get 40 minutes off thesymptom-to-needle time? Rethinking ER services leads to faster and wideruse of thrombolysis in stroke. Neurology. 2006;66(suppl 2):A326.10. Rodan LH, Kerr-Taylor M, Sahlas DJ, et al. Immediate impact of a citywideprehospital redirect protocol for increasing access to thrombolytic therapyfor acute stroke. Stroke. 2006;37:742.11. Kim D, Kaufman S, Starkman S, et al. Acute pre-hospital stroke care presentingto a single emergency room. Neurology. 2006;66(suppl 2):A65.12. Schlueter G, Nye PJ, Morales-Tatgenhorst D, et al. Redefining hyperacute: delivering neuroprotectants within two hours of stroke symptom onset.Stroke. 2006;37:750.