Prehospital Transport Time Intervals for Acute Stroke Patients

Brain injury mobile diagnostic system: Applications in civilian medical service and on the battlefield-General concept and medical aspects

To present the concept of a portable ultrasound tomography device for diagnosing traumatic and vascular brain lesions. The device consisting of multiple transcranial ultrasound probes placed on the surface of the head, specifically but not exclusively in natural acoustic windows. An integral part of the mobile diagnostic system (MDS) is a decision support system based on artificial intelligence algorithms utilizing information from: head images, laboratory data, and assessment of the patient's clinical condition. The MDS can significantly reduce the time from stroke onset to rtPA therapy in civilian medical services and support therapeutic and evacuation strategies in instances of brain and skull trauma on the battlefield.

Time intervals and distances travelled for prehospital ambulance stroke care: data from the randomised-controlled ambulance-based Rapid Intervention with Glyceryl trinitrate in Hypertensive stroke Trial-2 (RIGHT-2)

OBJECTIVES

Ambulances offer the first opportunity to evaluate hyperacute stroke treatments. In this study, we investigated the conduct of a hyperacute stroke study in the ambulance-based setting with a particular focus on timings and logistics of trial delivery.

DESIGN

Multicentre prospective, single-blind, parallel group randomised controlled trial.

SETTING

Eight National Health Service ambulance services in England and Wales; 54 acute stroke centres.

PARTICIPANTS

Paramedics enrolled 1149 patients assessed as likely to have a stroke, with Face, Arm, Speech and Time score (2 or 3), within 4 hours of symptom onset and systolic blood pressure >120 mm Hg.

INTERVENTIONS

Paramedics administered randomly assigned active transdermal glyceryl trinitrate or sham.

PRIMARY AND SECONDARY OUTCOMES

Modified Rankin scale at day 90. This paper focuses on response time intervals, distances travelled and baseline characteristics of patients, compared between ambulance services.

RESULTS

Paramedics enrolled 1149 patients between September 2015 and May 2018.

FINAL DIAGNOSIS

intracerebral haemorrhage 13%, ischaemic stroke 52%, transient ischaemic attack 9% and mimic 26%. Timings (min) were (median (25-75 centile)): onset to emergency call 19 (5-64); onset to randomisation 71 (45-116); total time at scene 33 (26-46); depart scene to hospital 15 (10-23); randomisation to hospital 24 (16-34) and onset to hospital 97 (71-141). Ambulances travelled (km) 10 (4-19) from scene to hospital. Timings and distances differed between ambulance service, for example, onset to randomisation (fastest 53 min, slowest 77 min; p<0.001), distance from scene to hospital (least 4 km, most 20 km; p<0.001).

CONCLUSION

We completed a large prehospital stroke trial involving a simple-to-administer intervention across multiple ambulance services. The time from onset to randomisation and modest distances travelled support the applicability of future large-scale paramedic-delivered ambulance-based stroke trials in urban and rural locations.

TRIAL REGISTRATION NUMBER

ISRCTN26986053.

Comparison of pre-hospital emergency services time intervals in patients with heart attack in Arak, Iran

Background:

After cardiac arrest, the possibility of death or irreversible complications will highly increase in the absence of cardiac resuscitation within 4 to 6 minutes. Accordingly, measuring the pre-hospital services time intervals is important for better management of emergency medical services delivery. The purpose of this study then was to investigate pre-hospital time intervals for patients with heart attack in Arak city, based on locations and time variables.

Methods:

This is a retrospective descriptive cross-sectional study, which was conducted at the Arak Emergency Medical Services (EMS) during 2017-2018. Data were analyzed by SPSS version 13.

Results:

The total number of heart attack patients registered in Arak emergency medical services was 2,659 of which 51% of patients were males. Six percent of patients were under 25 and about 49 percent were between 46 and 65 years old. The average of activation, response, on-scene, transportation, recovery and total time intervals were 3:30, 7:56, 15:15, 13:34, 11:07, 12:11, and 41:25, respectively. In the city area, the shortest and longest average response time intervals were in spring and winter, respectively. In out of the city area, the shortest average response time interval was in summer and the longest one in autumn. The shortest and the longest average response time intervals in the city area were in June and March, respectively, and in out of the city area, the shortest average response time interval was in June and the longest one in April.

Conclusions:

The shorter response and delivery time interval compared to the other studies may indicate improvement in the provision of EMS. Special attention should be paid to the facilities and equipment of vehicles during cold seasons to be in the shortest possible time. Also, training and informing the staff more about the code of cardiac patients along with general public education can help improve these intervals.

Accuracy of Emergency Medical Services Dispatcher and Crew Diagnosis of Stroke in Clinical Practice

BACKGROUND

Accurate recognition of stroke symptoms by Emergency Medical Services (EMS) is necessary for timely care of acute stroke patients. We assessed the accuracy of stroke diagnosis by EMS in clinical practice in a major US city.

METHODS AND RESULTS

Philadelphia Fire Department data were merged with data from a single comprehensive stroke center to identify patients diagnosed with stroke or TIA from 9/2009 to 10/2012. Sensitivity and positive predictive value (PPV) were calculated. Multivariable logistic regression identified variables associated with correct EMS diagnosis. There were 709 total cases, with 400 having a discharge diagnosis of stroke or TIA. EMS crew sensitivity was 57.5% and PPV was 69.1%. EMS crew identified 80.2% of strokes with National Institutes of Health Stroke Scale (NIHSS) ≥5 and symptom duration <6 h. In a multivariable model, correct EMS crew diagnosis was positively associated with NIHSS (NIHSS 5-9, OR 2.62, 95% CI 1.41-4.89; NIHSS ≥10, OR 4.56, 95% CI 2.29-9.09) and weakness (OR 2.28, 95% CI 1.35-3.85), and negatively associated with symptom duration >270 min (OR 0.41, 95% CI 0.25-0.68). EMS dispatchers identified 90 stroke cases that the EMS crew missed. EMS dispatcher or crew identified stroke with sensitivity of 80% and PPV of 50.9%, and EMS dispatcher or crew identified 90.5% of patients with NIHSS ≥5 and symptom duration <6 h.

CONCLUSION

Prehospital diagnosis of stroke has limited sensitivity, resulting in a high proportion of missed stroke cases. Dispatchers identified many strokes that EMS crews did not. Incorporating EMS dispatcher impression into regional protocols may maximize the effectiveness of hospital destination selection and pre-notification.

Identifying Key Words in 9-1-1 Calls for Stroke: A Mixed Methods Approach

OBJECTIVES

Identifying stroke during a 9-1-1 call is critical to timely prehospital care. However, emergency medical dispatchers (EMDs) recognize stroke in less than half of 9-1-1 calls, potentially due to the words used by callers to communicate stroke signs and symptoms. We hypothesized that callers do not typically use words and phrases considered to be classical descriptors of stroke, such as focal neurologic deficits, but that a mixed-methods approach can identify words and phrases commonly used by 9-1-1 callers to describe acute stroke victims.

METHODS

We performed a mixed-method, retrospective study of 9-1-1 call audio recordings for adult patients with confirmed stroke who were transported by ambulance in a large urban city. Content analysis, a qualitative methodology, and computational linguistics, a quantitative methodology, were used to identify key words and phrases used by 9-1-1 callers to describe acute stroke victims. Because a caller's level of emotional distress contributes to the communication during a 9-1-1 call, the Emotional Content and Cooperation Score was scored by a multidisciplinary team.

RESULTS

A total of 110 9-1-1 calls, received between June and September 2013, were analyzed. EMDs recognized stroke in 48% of calls, and the emotional state of most callers (95%) was calm. In 77% of calls in which EMDs recognized stroke, callers specifically used the word "stroke"; however, the word "stroke" was used in only 38% of calls. Vague, non-specific words and phrases were used to describe stroke victims' symptoms in 55% of calls, and 45% of callers used distractor words and phrases suggestive of non-stroke emergencies. Focal neurologic symptoms were described in 39% of calls. Computational linguistics identified 9 key words that were more commonly used in calls where the EMD identified stroke. These words were concordant with terms identified through qualitative content analysis.

CONCLUSIONS

Most 9-1-1 callers used vague, non-specific, or distractor words and phrases and infrequently provide classic stroke descriptions during 9-1-1 calls for stroke. Both qualitative and quantitative methodologies identified similar key words and phrases associated with accurate EMD stroke recognition. This study suggests that tools incorporating commonly used words and phrases could potentially improve EMD stroke recognition.

The early chain of care and risk of death in acute stroke in relation to the priority given at the dispatch centre: A multicentre observational study

BACKGROUND

The early chain of care is critical for stroke patients. The most important part is the so-called 'system delay' i.e. the delay time from call to the emergency medical services until a diagnosis is established (computer tomography).

AIM

The purpose of this study was to relate the initial priority level given by the dispatch centre to the early chain of care in acute stroke and to short-term and long-term mortality.

METHODS

All patients hospitalised with the first and the final diagnosis of acute stroke, 15 December 2010-15 April 2011, were recruited across nine hospitals, each hospital with a stroke care unit.

RESULTS

In all, 897 stroke patients were included. Priority at the dispatch centre: 54% received highest priority 1, 41% priority 2 and 5% priority 3. Median system delay from call to emergency medical services until diagnosis by computer tomography was 2 h and 52 min, 4 h and 49 min and 6 h and 33 min respectively in the three priority groups ( p<0.0001). There was a similarly strong association between priority level at the dispatch centre and system delay to arrival in a hospital ward, suspicion of stroke by the emergency medical services nurse as well as the physician on hospital admission and the proportion of patients given thrombolysis. Mortality during the subsequent 30 days was 22% among patients with priority 1 and 14% among patients with priority 2.

CONCLUSION

Patients given a lower priority level at the dispatch centre had the longest system delay. Although many of these patients died, the risk of death was highest among those given the highest priority.

Contemporary Prehospital Emergency Medical Services Response Times for Suspected Stroke in the United States

BACKGROUND AND PURPOSE

There are no contemporary national-level data on Emergency Medical Services (EMS) response times for suspected stroke in the United States (US). Because effective stroke treatment is time-dependent, we characterized response times for suspected stroke, and examined whether they met guideline recommendations.

METHODS

Using the National EMS Information System dataset, we included 911 calls for patients ≥ 18 years with an EMS provider impression of stroke. We examined variation in the total EMS response time by dispatch notification of stroke, age, sex, race, region, time of day, day of the week, as well as the proportion of EMS responses that met guideline recommended response times. Total EMS response time included call center dispatch time (receipt of call by dispatch to EMS being notified), EMS dispatch time (dispatch informing EMS to EMS starts moving), time to scene (EMS starts moving to EMS arrival on scene), time on scene (EMS arrival on scene to EMS leaving scene), and transport time (EMS leaving scene to reaching treatment facility).

RESULTS

We identified 184,179 events with primary impressions of stroke (mean age 70.4 ± 16.4 years, 55% male). Median total EMS response time was 36 (IQR 28.7-48.0) minutes. Longer response times were observed for patients aged 65-74 years, of white race, females, and from non-urban areas. Dispatch identification of stroke versus "other" was associated with marginally faster response times (36.0 versus 36.7 minutes, p < 0.01). When compared to recommended guidelines, 78% of EMS responses met dispatch delay of <1 minute, 72% met time to scene of <8 minutes, and 46% met on-scene time of <15 minutes.

CONCLUSIONS

In the United States, time from receipt of 9-1-1 calls to treatment center arrival takes a median of 36 minutes for stroke patients, an improvement upon previously published times. The fact that 22%-46% of EMS responses did not meet stroke guidelines highlights an opportunity for improvement. Future studies should examine EMS diagnostic accuracy nationally or regionally using outcomes based approaches, as accurate recognition of prehospital strokes is vital in order to improve response times, adhere to guidelines, and ultimately provide timely and effective stroke treatment.

The Effect of Telemedicine on Access to Acute Stroke Care in Texas: The Story of Age Inequalities

Background. Ischemic stroke is a time sensitive disease with the effectiveness of treatment decreasing over time. Treatment is more likely to occur at Primary Stroke Centers (PSC); thus rapid access to acute stroke care through stand-alone PSCs or telemedicine (TM) is vital for all Americans. The objective of this study is to determine if disparities exist in access to PSCs or the extended access to acute stroke care provided by TM. Methods. Data from the US Census Bureau and the 2010 Neilson Claritas Demographic Estimation Program, American Hospital Association annual survey, and The Joint Commission list of PSCs and survey response data for all hospitals in the state of Texas were used. Results. Over 64% of block groups had 60-minute ground access to acute stroke care. The odds of a block group having 60-minute access to acute stroke care decreased with age, despite adjustment for sex, race, ethnicity, socioeconomic status, urbanization, and total population. Conclusion. Our survey of Texas hospitals found that as the median age of a block group increased, the odds of having access to acute stroke care decreased.

The effects of telemedicine on racial and ethnic disparities in access to acute stroke care

Racial and ethnic disparities have been previously reported in acute stroke care. We sought to determine the effect of telemedicine (TM) on access to acute stroke care for racial and ethnic minorities in the state of Texas. Data were collected from the US Census Bureau, The Joint Commission and the American Hospital Association. Access for racial and ethnic minorities was determined by summing the population that could reach a primary stroke centre (PSC) or telemedicine spoke within specified time intervals using validated models. TM extended access to stroke expertise by 1.5 million residents. The odds of providing 60-minute access via TM were similar in Blacks and Whites (prevalence odds ratios (POR) 1.000, 95% CI 1.000-1.000), even after adjustment for urbanization (POR 1.000, 95% CI 1.000-1.001). The odds of providing access via TM were also similar for Hispanics and non-Hispanics (POR 1.000, 95% CI 1.000-1.000), even after adjustment for urbanization (POR 1.000, 95% CI 1.000-1.000). We found that telemedicine increased access to acute stroke care for 1.5 million Texans. While racial and ethnic disparities exist in other components of stroke care, we did not find evidence of disparities in access to the acute stroke expertise afforded by telemedicine.

Optimization modeling to maximize population access to comprehensive stroke centers

OBJECTIVE

The location of comprehensive stroke centers (CSCs) is critical to ensuring rapid access to acute stroke therapies; we conducted a population-level virtual trial simulating change in access to CSCs using optimization modeling to selectively convert primary stroke centers (PSCs) to CSCs.

METHODS

Up to 20 certified PSCs per state were selected for conversion to maximize the population with 60-minute CSC access by ground and air. Access was compared across states based on region and the presence of state-level emergency medical service policies preferentially routing patients to stroke centers.

RESULTS

In 2010, there were 811 Joint Commission PSCs and 0 CSCs in the United States. Of the US population, 65.8% had 60-minute ground access to PSCs. After adding up to 20 optimally located CSCs per state, 63.1% of the US population had 60-minute ground access and 86.0% had 60-minute ground/air access to a CSC. Across states, median CSC access was 55.7% by ground (interquartile range 35.7%-71.5%) and 85.3% by ground/air (interquartile range 59.8%-92.1%). Ground access was lower in Stroke Belt states compared with non-Stroke Belt states (32.0% vs 58.6%, p = 0.02) and lower in states without emergency medical service routing policies (52.7% vs 68.3%, p = 0.04).

CONCLUSION

Optimal system simulation can be used to develop efficient care systems that maximize accessibility. Under optimal conditions, a large proportion of the US population will be unable to access a CSC within 60 minutes.

Prehospital use of magnesium sulfate as neuroprotection in acute stroke

BACKGROUND

Magnesium sulfate is neuroprotective in preclinical models of stroke and has shown signals of potential efficacy with an acceptable safety profile when delivered early after stroke onset in humans. Delayed initiation of neuroprotective agents has hindered earlier phase 3 trials of neuroprotective agents.

METHODS

We randomly assigned patients with suspected stroke to receive either intravenous magnesium sulfate or placebo, beginning within 2 hours after symptom onset. A loading dose was initiated by paramedics before the patient arrived at the hospital, and a 24-hour maintenance infusion was started on the patient's arrival at the hospital. The primary outcome was the degree of disability at 90 days, as measured by scores on the modified Rankin scale (range, 0 to 6, with higher scores indicating greater disability).

RESULTS

Among the 1700 enrolled patients (857 in the magnesium group and 843 in the placebo group), the mean (±SD) age was 69±13 years, 42.6% were women, and the mean pretreatment score on the Los Angeles Motor Scale of stroke severity (range, 0 to 10, with higher scores indicating greater motor deficits) was 3.7±1.3. The final diagnosis of the qualifying event was cerebral ischemia in 73.3% of patients, intracranial hemorrhage in 22.8%, and a stroke-mimicking condition in 3.9%. The median interval between the time the patient was last known to be free of stroke symptoms and the start of the study-drug infusion was 45 minutes (interquartile range, 35 to 62), and 74.3% of patients received the study-drug infusion within the first hour after symptom onset. There was no significant shift in the distribution of 90-day disability outcomes on the global modified Rankin scale between patients in the magnesium group and those in the placebo group (P=0.28 by the Cochran-Mantel-Haenszel test); mean scores at 90 days did not differ between the magnesium group and the placebo group (2.7 in each group, P=1.00). No significant between-group differences were noted with respect to mortality (15.4% in the magnesium group and 15.5% in the placebo group, P=0.95) or all serious adverse events.

CONCLUSIONS

Prehospital initiation of magnesium sulfate therapy was safe and allowed the start of therapy within 2 hours after the onset of stroke symptoms, but it did not improve disability outcomes at 90 days. (Funded by the National Institute of Neurological Disorders and Stroke; FAST-MAG ClinicalTrials.gov number, NCT00059332.).

Disparities in accessibility of certified primary stroke centers

BACKGROUND AND PURPOSE

We examine whether the proportion of the US population with ≤60 minute access to Primary Stroke Centers (PSCs) varies based on geographic and demographic factors.

METHODS

Population level access to PSCs within 60 minutes was estimated using validated models of prehospital time accounting for critical prehospital time intervals and existing road networks. We examined the association between geographic factors, demographic factors, and access to care. Multivariable models quantified the association between demographics and PSC access for the entire United States and then stratified by urbanicity.

RESULTS

Of the 309 million people in the United States, 65.8% had ≤60 minute PSC access by ground ambulance (87% major cities, 59% minor cities, 9% suburbs, and 1% rural). PSC access was lower in stroke belt states (44% versus 69%). Non-whites were more likely to have access than whites (77% versus 62%), and Hispanics were more likely to have access than non-Hispanics (78% versus 64%). Demographics were not meaningfully associated with access in major cities or suburbs. In smaller cities, there was less access in areas with lower income, less education, more uninsured, more Medicare and Medicaid eligibles, lower healthcare utilization, and healthcare resources.

CONCLUSIONS

There are significant geographic disparities in access to PSCs. Access is limited in nonurban areas. Despite the higher burden of cerebrovascular disease in stroke belt states, access to care is lower in these areas. Selecting demographic and healthcare factors is strongly associated with access to care in smaller cities, but not in other areas, including major cities.

An association between systolic blood pressure and stroke among patients with impaired consciousness in out-of-hospital emergency settings

Background

Stroke is difficult to diagnose when consciousness is disturbed. However few reports have discussed the clinical predictors of stroke in out-of-hospital emergency settings. This study aims to evaluate the association between initial systolic blood pressure (SBP) value measured by emergency medical service (EMS) and diagnosis of stroke among impaired consciousness patients.

Methods

We included all patients aged 18 years or older who were treated and transported by EMS, and had impaired consciousness (Japan Coma Scale ≧ 1) in Osaka City (2.7 million), Japan from January 1, 1998 through December 31, 2007. Data were prospectively collected by EMS personnel using a study-specific case report form. Multiple logistic regressions assessed the relationship between initial SBP and stroke and its subtypes adjusted for possible confounding factors.

Results

During these 10 years, a total of 1,840,784 emergency patients who were treated and transported by EMS were documented during the study period in Osaka City. Out of 128,678 with impaired consciousness, 106,706 who had prehospital SBP measurements in the field were eligible for our analyses. The proportion of patients with severe impaired consciousness significantly increased from 14.5% in the <100 mmHg SBP group to 27.6% in the > =200 mmHg SBP group (P for trend <0.001). The occurrence of stroke significantly increased with increasing SBP (adjusted odd ratio [AOR] 1.34, 95% confidence interval [CI] 1.33 to 1.35), and the AOR of the SBP > =200 mmHg group versus the SBP 101-120 mmHg group was 5.26 (95% CI 4.93 to 5.60). The AOR of the SBP > =200 mmHg group versus the SBP 101-120 mmHg group was 9.76 in subarachnoid hemorrhage (SAH), 16.16 in intracranial hemorrhage (ICH), and 1.52 in ischemic stroke (IS), and the AOR of SAH and ICH was greater than that of IS.

Conclusions

Elevated SBP among emergency patients with impaired consciousness in the field was associated with increased diagnosis of stroke.

Impact of Telemedicine on Access to Acute Stroke Care in the State of Texas

Background

To examine the impact of telemedicine (TM) on access to acute stroke care and expertise in the state of Texas.

Methods

Texas hospitals were surveyed using a standard questionnaire and categorized as: (1) stand-alone Primary Stroke Centers (PSC) not using TM for acute stroke care, (2) PSC using TM for acute stroke care, (3) non-PSC hospitals using TM for acute stroke care, or (4) non-PSC hospitals not using TM for acute stroke care. Population data were obtained from the U.S. Census Bureau and the Neilson Claritas Demographic Estimation Program. Access within 60 min to a designated facility was calculated at the block group level.

Results

Over 75% of Texans had 60-min access to a stand-alone PSC. Including PSC using TM increased access by 6.5%. Adding non-PSC that use TM for acute stroke care provided 60-min access for an additional 2% of Texans, leaving 16% of Texans without 60-min access to acute stroke care. Approximately 62% of Texans had 60-min access to more than one type of facility that provided acute stroke care.

Conclusion

The use of TM in the state of Texas brought 60-min access to >2 million Texans who otherwise would not have had access to acute stroke expertise. Our findings demonstrate that using TM for acute stroke has the ability to provide neurologically underserved areas access to acute stroke care.

The association between prehospital care and in-hospital treatment decisions in acute stroke: a cohort study

BACKGROUND

Hospital prealerting in acute stroke improves the timeliness of subsequent treatment, but little is known about the impact of prehospital assessments on in-hospital care.

OBJECTIVE

Examine the association between prehospital assessments and notification by emergency medical service staff on the subsequent acute stroke care pathway.

METHODS

This was a cohort study of linked patient medical records. Consenting patients with a diagnosis of stroke were recruited from two urban hospitals. Data from patient medical records were extracted and entered into a Cox regression analysis to investigate the association between time to CT request and recording of onset time, stroke recognition (using the Face Arm Speech Test (FAST)) and sending of a prealert message.

RESULTS

151 patients (aged 71±15 years) travelled to hospital via ambulance and were eligible for this analysis. Time of symptom onset was recorded in 61 (40%) cases, the FAST test was positive in 114 (75%) and a prealert message was sent in 65 (44%). Following adjustment for confounding, patients who had time of onset recorded (HR 0.73, 95% CI 0.52 to 1.03), were FAST-positive (HR 0.54, 95% CI 0.37 to 0.80) or were prealerted (HR 0.26, 95% CI 0.18 to 0.38), were more likely to receive a timely CT request in hospital.

CONCLUSIONS

This study highlights the importance of hospital prealerting, accurate stroke recognition, and recording of onset time. Those not recognised with stroke in a prehospital setting appear to be excluded from the possibility of rapid treatment in hospital, even before they have been seen by a specialist.

An evaluation of emergency medical services stroke protocols and scene times

BACKGROUND

Acute stroke patients require immediate medical attention. Therefore, American Stroke Association guidelines recommend that for suspected stroke cases, emergency medical services (EMS) personnel spend less than 15 minutes on-scene at least 90% of the time. However, not all EMS providers include specific scene time limits in their stroke patient care protocols.

OBJECTIVE

We sought to determine whether having a protocol with a specific scene time limit was associated with less time EMS spent on scene. Methods. Stroke protocols from the 100 EMS systems in North Carolina were collected and abstracted for scene time instructions. Suspected stroke events occurring in 2009 were analyzed using data from the North Carolina Prehospital Medical Information System. Scene time was defined as the time from EMS arrival at the scene to departure with the patient. Quantile regression was used to estimate how the 90th percentile of the scene time distribution varied by systems with protocol instructions limiting scene time, adjusting for system patient volume and metropolitan status.

RESULTS

In 2009, 23 EMS systems in North Carolina had no instructions regarding scene time; 73 had general instructions to minimize scene time; and 4 had a specific limit for scene time (i.e., 10 or 15 min). Among 9,723 eligible suspected stroke events, mean scene time was 15.9 minutes (standard deviation 6.9 min) and median scene time was 15.0 minutes (90th percentile 24.3 min). In adjusted quantile regression models, the estimated reduction in the 90th percentile scene time, comparing protocols with a specific time limit to no instructions, was 2.2 minutes (95% confidence interval 1.3, 3.1 min). The difference in 90th percentile scene time between general and absent instructions was not statistically different (0.7 min [95% confidence interval -0.1, 1.4 min]).

CONCLUSION

Protocols with specific scene time limits were associated with EMS crews spending less time at the scene while general instructions were not. These findings suggest EMS systems can modestly improve scene times for stroke by specifying a time limit in their protocols.

Guidelines for the early management of patients with acute ischemic stroke: a guideline for healthcare professionals from the American Heart Association/American Stroke Association

BACKGROUND AND PURPOSE

The authors present an overview of the current evidence and management recommendations for evaluation and treatment of adults with acute ischemic stroke. The intended audiences are prehospital care providers, physicians, allied health professionals, and hospital administrators responsible for the care of acute ischemic stroke patients within the first 48 hours from stroke onset. These guidelines supersede the prior 2007 guidelines and 2009 updates.

METHODS

Members of the writing committee were appointed by the American Stroke Association Stroke Council's Scientific Statement Oversight Committee, representing various areas of medical expertise. Strict adherence to the American Heart Association conflict of interest policy was maintained throughout the consensus process. Panel members were assigned topics relevant to their areas of expertise, reviewed the stroke literature with emphasis on publications since the prior guidelines, and drafted recommendations in accordance with the American Heart Association Stroke Council's Level of Evidence grading algorithm.

RESULTS

The goal of these guidelines is to limit the morbidity and mortality associated with stroke. The guidelines support the overarching concept of stroke systems of care and detail aspects of stroke care from patient recognition; emergency medical services activation, transport, and triage; through the initial hours in the emergency department and stroke unit. The guideline discusses early stroke evaluation and general medical care, as well as ischemic stroke, specific interventions such as reperfusion strategies, and general physiological optimization for cerebral resuscitation.

CONCLUSIONS

Because many of the recommendations are based on limited data, additional research on treatment of acute ischemic stroke remains urgently needed.