Stroke: prospective evaluation of a prehospital ...

American Journal of Emergency Medicine xxx (2014) xxx–xxx

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Original Contribution

Stroke: prospective evaluation of a prehospital management process based on rescuers under medical direction☆,☆☆ Laure Alhanati, MD, Stéphane Dubourdieu, MD, Clément Hoffmann, MD, Francis Béguec, MD, Stéphane Travers, MD, Hugues Lefort, MD, Olga Maurin, MD, Daniel Jost, MD, Laurent Domanski, MD, Jean-Pierre Tourtier, MD ⁎ Fire Brigade of Paris, Emergency Medical Service, 1 Place Jules Renard, 75017 Paris, France

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Article history: Received 9 October 2013 Received in revised form 2 January 2014 Accepted 22 January 2014 Available online xxxx

a b s t r a c t Background: Improving access to thrombolytic therapy for patients with ischemic stroke is challenging. We assessed a prehospital process based on firemen rescuers under strict medical direction, aimed at facilitating thrombolysis of eligible patients. Methods: This was a prospective observational study conducted over 4 months in Paris, France. Prehospital patients with suspected stroke were included after telephone consultation with a physician. If the time since the onset of symptoms was less than 6 hours, patients were transported directly to a neurovascular unit (NVU); if symptom onset was more than 6 hours ago, they were transported to an emergency department (ED). Confirmation of stroke diagnosis, the rate of thrombolysis, and the time intervals between the call and hospital arrival and imaging were assessed. Comparison used Fisher exact test. Results: Of the 271 patients transported to an NVU, 218 were diagnosed with a stroke (166 with ischemic stroke), 69 received thrombolytic therapy, and the mean stroke-thrombolysis interval was 150 minutes. Of 64 patients admitted to the ED, 36 patients had a stroke (ischemic, 24). None were thrombolysed. Globally, 36% of ischemic strokes were thrombolysed (27% of all strokes diagnosed). The mean interval call-hospital was 65 minutes (ED vs NVU, P = .61). The interval call-imaging was 202 minutes (interquartile range, 105.5-254.5) for ED and 92 minutes (interquartile range, 77-116) for NVU (P b .001). Conclusions: The prehospital management of stroke by rescuers, under strict medical direction, seemed to be feasible and effective for selection of patients with stroke in an urban environment and may improve the access to thrombolysis. © 2014 Elsevier Inc. All rights reserved.

1. Introduction Cerebrovascular accident (stroke) is a main cause of death worldwide and is one of the most common causes of disability in developed countries [1]. Strokes affect 130 000 people each year in France, making stroke the leading cause of acquired disability in adults and the third leading cause of mortality [2]. Approximately 90% of all strokes are due to cerebral ischemia [3]. The specific treatment for ischemic stroke is recanalization of occluded arteries within the ☆ Contribution of authors: Alhanati L: Design of the study, acquisition of data, analysis and interpretation of data, drafting the article. Dubourdieu S: Conception and design of the study, analysis and interpretation of data. Hoffmann C: Acquisition of data. Béguec F: Acquisition of data. Travers S, Lefort H, Maurin O, Jost D, Domanski L: Acquisition of data, analysis and interpretation of data. Domanski L: Interpretation of data, design of the study. Tourtier JP: Design of the study, drafting the article intellectual content, final approval of the version to be submitted. ☆☆ Disclosures: No funding of any kind, no conflict of interest of any kind for all authors. ⁎ Corresponding author. Fire Brigade of Paris, Emergency Medical Service, 1 Place Jules Renard, 75017 Paris. Tel.: +33 670208162; fax: +33 156796754. E-mail address: [email protected] (J.-P. Tourtier).

very first hours of symptom onset [4-6]. Less than one-third of patients with acute stroke arrive at the hospital early enough to receive thrombolytic treatment, and less than 5% actually receive it [711]. Of those patients, outcomes are closely related to the time to treatment [12–14]. There is rare published trial of prehospital stroke diagnosis and treatment; there are several reports of prehospital delay in acute stroke care. The reported median times from symptom onset to arrival at hospital vary strongly, ranging from 3 to 6 hours, and median times from arrival at hospital to thrombolysis were assessed to be more than 1 hour [15-19]. The timely and accurate diagnosis of acute ischemic stroke by prehospital providers is critical in the chain of survival in stroke, and chances of successful treatment are time dependent. Accurate diagnosis in the field may lead to improved treatment intervals such as door-to-imaging and door-to-treatment times, which could improve chances of success. In accordance with international guidelines, the fire brigade of Paris (Brigade des Sapeurs-Pompiers de Paris [BSPP]) has developed a specific prehospital management procedure for stroke. It is based on

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Please cite this article as: Alhanati L, et al, Stroke: prospective evaluation of a prehospital management process based on rescuers under medical direction, Am J Emerg Med (2014), http://dx.doi.org/10.1016/j.ajem.2014.01.034

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L. Alhanati et al. / American Journal of Emergency Medicine xxx (2014) xxx–xxx

management by firemen rescuers (under strict medical direction) and immediate transport. The aim of this procedure is to facilitate rapid admission to a neurovascular unit (NVU) after medical control of the patient's assessment and after contacting a neurologist [20]. The objective of this study was to prospectively evaluate this prehospital process of stroke management for improvement in diagnosis, treatment, and time intervals. 2. Methods 2.1. Geographical situation The BSPP employs 8500 firemen, and its mission is to provide assistance and first-aid care to residents of Paris and the 3 adjacent districts, which represents a population of 10 million people. There are 40 hospital emergency departments (ED) and 14 NVUs in this area. The fire brigade of Paris performs 500 000 prehospital emergency interventions per year and is equipped with ambulances (Véhicules de Secours et d’Assistance aux Victimes) with a team of 3 fireman rescuers as well as medical transportation means: intensive care ambulances with a physician and a nurse. Telephone calls (emergency numbers in Europe: 112, emergencies; 18, fire brigade) from the population requesting an intervention (2.1 million calls per year) are analyzed by specialized operators and by physicians in the coordination center, and a rescue team can be dispatched immediately.

symptoms was considered to be potentially compatible with thrombolytic therapy in the case of an ischemic stroke (4.5 hours according to ischemic stroke recommendations and up to 6 hours for certain types of stroke such as those involving the basilar trunk) [14]. If the time since the onset of symptoms was less than 6 hours, the physician of the coordination center would contact the closest NVU with an available place for the patient. A contraindication to thrombolysis did not exclude the transfer to an NVU [22]. When direct transport to an NVU was decided, the patient was transported urgently. When the time since the onset of symptoms was longer than 6 hours, but less than 24 hours, the triage physician would seek the opinion of the closest NVU's neurologist to determine whether the patient should be transferred directly to the NVU, depending on his/her clinical status and available place, or to a nearby ED (ED management process). The paramedics would systematically collect the patient's prescriptions and also request a member of the patient's family to accompany them or, failing this, would record a telephone number where the relative could be reached. During transport, the patient was placed in a supine position in the absence of contraindication. The patient was placed under close neurologic and hemodynamic monitoring and given oxygen inhalation. In the event of any neurologic deterioration during transport, the coordinating physician was urgently recontacted to decide the intervention of an intensive care ambulance (sent on the spot with a physician).

2.2. The prehospital stroke management process

2.3. Data collection

Before 2007, following the field rescuers evaluation, a medical team was called to confirm the diagnosis and practice the transport to NVU or emergency medical services, depending mainly on physician assessment and disponibility of hospital. In February 2007, an innovative specific process for stroke management by rescuers team aimed at facilitating rapid admission to an NVU was set up by the Paris Fire Brigade (at that time, prehospital management of stroke was generally ensured by a medical team). As a result, following a call to the emergency number by the victim or the victim's family and in the absence of any immediate life-threatening situation detected at the time of the call, an ambulance (Véhicules de Secours et d’Assistance aux Victimes) teamed by 3 firemen rescuers was dispatched. The work has been approved by the appropriate ethical committees related to the institution. An on-the-spot assessment consisted of collecting the basic elements: age, sex, medical history and treatments, functional complaints, Glasgow score and signs of stroke on the Face Arm Speech Test diagnosis scale, heart rate, blood pressure, respiratory rate, oxygen saturation (SpO2), temperature, and capillary blood glucose when a blood glucose apparatus was available at the patient's home [21]. The firemen then transmitted assessment by telephone to a physician in the medical coordination center. In all cases of suspected stroke, this assessment was systematically reviewed by the physician who either confirmed or excluded the suspicion of stroke. A specific standard form was then used (Appendix 1) to record all the essential information items for the neurologist, including the time since the onset of symptoms (corresponding to the time when the patient's neurologic state was last considered to be normal by the witness or by the patient in the absence of a witness), a list of the patient's symptoms, and a decision-making algorithm. If the victim did not show any criteria for medical management (severe consciousness disorder, life-threatening respiratory or circulatory distress, associated seizures, suspected meningeal hemorrhage), the coordinating physician took into account the time since the onset of symptoms. In agreement with local neurologists, a maximum estimated interval of 6 hours since the onset of the first

This prospective cohort study was conducted from September 1 to December 31, 2011. All patients for whom the BSPP “Stroke” process was applied were included in the study, except for patients immediately presenting medical management criteria, for whom an intensive care ambulance was directly dispatched. The data were collected from various documents: specific Paris fire brigade coordinating physician forms (Appendix 1) recording age, sex, time of the emergency call, clinical symptoms, and transfer decision (to NVU or a hospital ED). Hospital discharge summaries were also obtained. Close contact was established with a corresponding physician in each department (NVU and EDs) to define the method for recovering hospital discharge summaries: they were either collected directly from the department, sent by letter, e-mailed, or faxed. For each case, the time since the onset of symptoms, the time of admission to the ward, the initial National Institute of Health Stroke Score (NIHSS), the time of medical imaging, whether thrombolysis was performed (including start and end times), any reasons why thrombolysis was not performed, and the final diagnosis were collected. For calculating time intervals, some definitions were used. The call-hospital interval matched with the interval between the time when the call was received by the triage center and the time of the patient's admission to hospital. The call-imaging interval was the interval between the call and the time at which neurologic imaging (computed tomography or magnetic resonance imaging) was performed. At last, the stroke-thrombolysis interval was the time interval between the time when the patient was last asymptomatic and the time at which thrombolysis was performed. The primary end points were the rate of stroke diagnosis confirmations among patients transported by firemen rescuers teams and the rate of patients who were thrombolysed in the NVU management process and in the ED management process. The secondary end points were the various prehospital management time intervals: call-hospital, call-imaging, and stroke onsetthrombolysis intervals. The data were anonymized and entered into an Excel spreadsheet. Statistical calculations were performed using Excel and Stata software. The quantitative data were compared by Fisher exact test.



3. Results From September 1 to December 31, 2011, 462 patients were included in the study: 225 women (48.7%) and 237 men (51.3%) with a median age of 72 years (interquartile range [IQR]25-75, 58-81). Of this total, 454 patients (98.3%) were transported by rescuers teams: 357 patients (77.3%) were transferred to an NVU and 97 were transferred to nearby EDs (21%). One patient (0.2%) received care by an additional medical team. Data concerning the initial triage were missing for 7 patients (1.5%) (Fig.). 3.1. Patients transferred to an NVU The median age of patients transferred to an NVU was 72 years (IQR, 58-82), and the median NIHSS score was 8 (IQR, 3-15.25). Hospital discharge summaries were obtained for 271 (76%) of these 357 patients and showed that 218 patients had a stroke, that is, 80.4% of the patients admitted to an NVU. The stroke was ischemic in more than three-fourths of cases (n = 166). The other diagnoses (n = 53) consisted of seizures with no abnormality on imaging in slightly more than 40% of cases (n = 23), psychiatric disorders (n = 6; 11.3%), and migraines with aura (n = 4; 7.6%). Two cases of hypoglycemia were also observed. Regarding thrombolysed patients, the mean stroke-thrombolysis interval was 150 minutes (IQR, 115-180). A total of 69 patients received thrombolytic therapy: 25.5% of the patients admitted to an NVU (69/271 discharge summaries available) and 42% of the patients transferred to an NVU with an ischemic stroke (69/166 confirmed ischemic strokes). 3.2. Patients transferred to a nearby ED The median age of patients transferred to a nearby ED was 77 years (IQR, 63-85), and the median NIHSS score was 7 (IQR, 4-15.5). Of the 97 patients admitted to a nearby ED, hospital discharge summaries were obtained for 64 (66%) and showed that 36 patients

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(56%) had a stroke, which was ischemic in three-fourths of cases. None of these patients were thrombolysed. Twenty-eight patients (44%) had not suffered a stroke. The final diagnoses were simple epileptic seizure in 9 cases, a psychiatric etiology in 4 cases, hypoglycemia in 2 cases, migraine in 2 patients, and a different etiology was identified in 11 patients (acute alcohol intoxication, brain metastasis, subdural hematoma, malaise/fainting, etc).

3.3. Intervals The median intervals were as follows: call-hospital, 64 minutes (IQR, 53-79) for admission to an ED vs 65 minutes (IQR, 52-75) for admission to an NVU (P = .61); call-imaging, 202 minutes (IQR, 105.5-254.5) for the ED and 92 minutes (IQR, 77-116) for the NVU (P b .001).

4. Discussion Globally, 36% of all ischemic strokes (with discharge summaries) were thrombolysed (27% of all strokes diagnosed). The thrombolysis rate was 42% for patients with a constituted cerebral infarction who were initially transferred to an NVU. This rate was much higher than the national and Parisian average rates. In France, in 2005, only 1% of patients received thrombolytic therapy, contrasting with European studies in which the percentage of patients potentially eligible for thrombolysis was estimated between 6% and 22% [23,24]. One of the possible explanations for this difference is that patients probably called emergency services when their symptoms were more straightforward and more severe, such as a motor deficit or a consciousness disorder. Indeed, most patients in this study had motor deficits (80% of patients transferred to an NVU). Of the 254 patients with confirmed stroke in this study (patients transferred to an NVU and patients transferred to an ED), 218 (85.8%) were directly transferred to an NVU. This rate was much higher than the national or even Paris region data, which estimated in 2009 that around 27% of stroke victims were directly transferred to an NVU [25].

Fig. Flow of patients.


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This high rate, therefore, suggested the interest of the management process, under strict medical regulation. Relatively short management times were observed for patients transferred directly to an NVU: imaging was performed with an average of 92 minutes after the call vs 202 minutes for patients transferred to EDs (P b .05), suggesting the value of hospital process that is ready to admit patients and to prioritize their access to brain imaging 24 hours a day. As emergency centers are more ubiquitous than NVUs, it could also be argue that resources would likely be better spent on ED-based systems to improve efficiency in diagnosing and treating patients with acute ischemic stroke. The interval call-hospital time would seem difficult to reduce, given the number of basic steps, which includes management time for the initial call, intervention arrival time, time required to perform the firemen rescuers assessment, search for an available place, and transfer time. This time interval was identical whether patients were transferred to an ED or an NVU. A recent British study showed that only 39.5% of patients reach hospital before the third hour of symptoms and 41.2% reach hospital within 4.5 hours [26]. The Centers for Disease Control and Prevention study, published in 2007, also showed that patients transferred by ambulance reached hospital in an average of 94 minutes after the onset of the symptoms vs 172 minutes for patients who arrived at the hospital by their own means [27]. To our knowledge, few studies invested prospectively the same topic. In Finland, after an intensive prehospital and hospital restructuring program, the median total time delay from symptom onset to thrombolytic intervention decreased from 149 to 112 minutes [28]. If in-hospital delays decreased significantly from 67 to 34 minutes, the median prehospital delay stayed unchanged. Recently, in Germany, innovative and costly prehospital strategy based on specialized ambulance (equipped with a computed tomographic scanner, point-of-care laboratory, and telemedicine connection; approximately €300 000) has permitted to obtain an enthusiastic median time from symptom onset to therapy decision of only 56 minutes, with a high level of evidence (randomized controlled trial) [29]. Moreover, transcranial ultrasound for stroke diagnosis has been described, and first clinical trials as well as numerous preclinical work suggest that ultrasound can be used to accelerate clot lysis (sonothrombolysis) in the presence as well as in the absence of tissue plasminogen activator [30]. Our study presents a number of limitations, in particular, a selection bias: the fire brigade of Paris manages an essentially urban population with a dense hospital network. The Parisian region has considerable medical resources, including 14 NVUs. It would, therefore, seem difficult to fully transpose the results observed in the Paris region to other districts, where emergency services are not organized in the same way and where NVUs may be located at much greater distances. In addition, the delivery model for prehospital care is very different across the world, which makes comparisons difficult. Another limitation of this study was the number of missing discharge summaries, resulting in missing data.

5. Conclusions It appeared feasible for rescuers, under strict medical control, to diagnose stroke and rapidly transport these patients to an appropriate destination in an urban environment, which may improve the access to thrombolysis. However, there are still possibilities for improvement on the efficiency of this procedure: continued training of firemen rescuers and medical guidance as well as an increased number of available beds in NVUs are needed to facilitate access to care for the greatest number of stroke patients. Further studies will, therefore, be needed to regularly reassess this management process and further improve the time intervals involved and, hopefully, improve the functional prognosis for the patients

concerned. More broadly, audit of prehospital process of care for stroke must be encouraged. References [1] Rothwell PM, Coull AJ, Silver LE, et al. Population-based study of event-rate, incidence, case fatality, and mortality for all acute vascular events in all arterial territories (Oxford Vascular Study). Lancet 2005;366:1773–83. [2] Aboderin I, Venables G. Stroke management in Europe. Pan European Consensus Meeting on Stroke Management. Intern Med 1996;240:169–71. [3] Caplan LR, Hier DB, D’Cruz I, et al. Cerebral embolism in the Michael Reese Registry. Stroke 1983;14:530–40. [4] The National Institute of Neurological Disorders and Stroke rt-PA Stroke Study Group. Tissue plasminogen activator for acute ischemic stroke. N Engl J Med 1995;333:1581–8. [5] Adams Jr HP, del Zoppo G, Alberts MJ, et al. Guidelines for the early management of adults with ischemic stroke: a guideline from the American Heart Association/American Stroke Association Stroke Council, Clinical Cardiology Council, Cardiovascular Radiology and Intervention Council, and the Atherosclerotic Peripheral Vascular Disease and Quality of Care Outcomes in Research Interdisciplinary Working Groups: The American Academy of Neurology affirms the value of this guideline as an educational tool for neurologists. Circulation 2007;115:e478–534. [6] European Stroke Organisation Executive Committee. Guidelines for management of ischaemic stroke and transient ischaemic attack 2008. Cerebrovasc Dis 2008;25: 457–507. [7] Katzan IL, Hammer MD, Hixson ED, Furlan AJ, Abou-Chebl A, Nadzam DM. Utilization of intravenous tissue plasminogen activator for acute ischemic stroke. Arch Neurol 2004;61:346–50. [8] Lichtman JH, Watanabe E, Allen NB, Jones B, Dostal J, Goldstein LB. Hospital arrival time and intravenous t-PA use in US academic medical centers, 2001-2004. Stroke 2009;40:3845–50. [9] Reeves MJ, Broderick JP, Frankel M, et al. The Paul Coverdell National Acute Stroke Registry: initial results from four prototypes. Am J Prev Med 2006;31:S202–9. [10] Albers GW, Olivot JM. Intravenous alteplase for ischaemic stroke. Lancet 2007;369:249–50. [11] California Acute Stroke Pilot Registry (CASPR) Investigators. Prioritizing interventions to improve rates of thrombolysis for ischemic stroke. Neurology 2005;64:654–9. [12] Panagos PD. The approach to optimizing stroke care. Am J Emerg Med 2008;26:808–16. [13] Hacke W, Kaste M, Bluhmki E, et al. Thrombolysis with alteplase 3 to 4.5 hours after acute ischemic stroke. N Engl J Med 2008;359:1317–29. [14] Saver JL. Time is brain quantified. Stroke 2006;37:263–6. [15] O’Brien PC, Fleming TR. A multiple testing procedure for clinical trial. Biometrics 1979;35:549–56. [16] Evenason KR, Rosamond WD, Morris DL. Prehospital and in-hospital delays in acute stroke care. Neuroepidemiology 2001;20:65–76. [17] Fonarow GC, Smith EE, Saver JL, et al. Timeliness of tissue-type plasminogen activator therapy in acute ischemic stroke: patient characteristics, hospital factors, and outcomes associated with door-to-needle times within 60 minutes. Circulation 2011;123:750–8. [18] Asplund K, Glader EL, Norrving B, et al. Effects of extending the time window of thrombolysis to 4.5 hours: observations in the Swedish stroke register (RiksStroke). Stroke 2011;42:2492–7. [19] Price CI, Clement F, Gray J, Donaldson C, Ford GA. Systematic review of stroke thrombolysis service configuration. Expert Rev Neurother 2009;9:211–33. [20] Adams H, Adams R, Del Zoppo G, Goldstein LB. Guidelines for the early management of patients with ischemic stroke: 2005 guidelines update a scientific statement from the Stroke Council of the American Heart Association/American Stroke Association. Stroke 2005;36:916–23. [21] Mohd Nor A, McAllister C, Louw SJ, Dyker AG, Davis M, et al. Agreement between ambulance paramedic- and physician-recorded neurological signs with Face Arm Speech Test (FAST) in acute stroke patients. Stroke 2004;35:1355–9. [22] Govan L, Weir C, Langhorne P. Organized inpatient (stroke unit) care for stroke. Stroke 2008;3:2402–3. [23] Collins D, O Neil D, Mc Cormaack P. Potential for treatment with thrombolysis in an Irish stroke unit. Ir Med J 1999;92:236–8. [24] Fiorelli M, Falcou A. The Rome emergency departments network for acute stroke: pilot study on incidence, referral pathways, and eligibility for thrombolytic therapy in Rome urban area. TajL NeuroScience 1999;20:S137. [25] de Peretti C, Nicolau J, Tuppin P, Schnitzler A, Woimant F. Acute and post-acute hospitalizations for stroke in France: recent improvements (2007-2009). Presse Med 2012;41:491–503. [26] Addo J, Ayis S, Leon J, Rudd AG, McKevitt C, Wolfe CD. Delay in presentation after an acute stroke in a multiethnic population in South London: the South London Stroke Register. J Am Heart Assoc 2012;1:e001685. [27] Centers for Disease Control and Prevention (CDC) Prehospital and hospital delays after stroke onset–United States, 2005-2006. MMWR Morb Mortal Wkly Rep. 2007; 18:56: 474-8. [28] Puolakka T, Vayrynen T, Happola O, Soinne L, Kuisma M, Lindsberg PJ. Sequential analysis of pretreatment delays in stroke thrombolysis. Acad Emerg Med 2010;17: 965–9. [29] Walter S, Kostopoulos P, Haass A, Keller I, Lesmeister M, Schlechtriemen T, et al. Diagnosis and treatment of patients with stroke in a mobile stroke unit versus in hospital: a randomised controlled trial. Lancet Neurol 2012;11(5):397–404. [30] Hölscher T, Dunford JV, Schlachetzki F, et al. Prehospital stroke diagnosis and treatment in ambulances and helicopters-a concept paper. Am J Emerg Med 2013;31:743–7.



Appendix 1. BSPP Medical Regulation Chart for a Suspected Stroke Patient


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