- The chain of events favoring good functional outcome from an acute ischemic stroke begins with the recognition of stroke when it occurs.
- Data show that the public’s knowledge of stroke warning signs remains poor.
- In one study, fewer than half of 9-1-1 calls for stroke events were made within one hour of symptom onset, and fewer than half of those callers thought stroke was the cause of their symptoms.
- Many studies have demonstrated that intense and ongoing public education about the signs and symptoms of stroke improves stroke recognition.
- The California Acute Stroke Pilot Registry (CASPR) reported that the expected overall rate of fibrinolytic treatment within 3 hours could be increased from 4.3% to 28.6% if all patients arrived early after onset.
- Public education campaigns feature one of two stroke recognition tools:
- The 5 “Suddens”
- Sudden weakness
- Sudden speech difficulty
- Sudden visual loss
- Sudden dizziness
- Sudden, severe headache
- FAST (Face, Arm, Speech, Time)
- One or more of face weakness, arm weakness, and speech difficulty symptoms are present in 88% of all strokes and transient ischemic attacks (TIAs).
Table 1. Features of Clinical Situations Mimicking Stroke
Diagnosis and Features
- Lack of objective cranial nerve findings, neurological findings in a nonvascular distribution, inconsistent examination
- History of seizures, witnessed seizure activity, postictal period
- History of diabetes, low serum glucose, decreased level of consciousness
- Migraine with aura
- History of similar events, preceding aura, headache
- Hypertensive encephalopathy
- Headache, delirium, significant hypertension, cortical blindness, cerebral edema, seizure
- Wernicke’s encephalopathy
- History of alcohol abuse, ataxia, ophthalmoplegia, confusion
- CNS abscess
- History of drug abuse, endocarditis, medical device implant with fever
- CNS tumor
- Gradual progression of symptoms, other primary malignancy, seizure at onset
- Drug toxicity
- Lithium, phenytoin, carbamazepine
Table 2. National Institutes of Health Stroke Scale (NIHSS)View Calculator
Table 3. Immediate Diagnostic Studies: Evaluation of a Patient With Suspected Acute Ischemic Stroke
- Noncontrast brain CT or brain MRI
- Blood glucose
- Oxygen saturation
- Serum electrolytes/renal function testsa
- Complete blood count, including platelet counta
- Markers of cardiac ischemiaa
- Prothrombin time/INRa
- Activated partial thromboplastin timea
- TT and/or ECT if it is suspected the patient is taking direct thrombin inhibitors or direct factor Xa inhibitors
- Hepatic function tests
- Toxicology screen
- Blood alcohol level
- Pregnancy test
- Arterial blood gas tests if hypoxia is suspected
- Chest radiography if lung disease is suspected
- Lumbar puncture if subarachnoid hemorrhage is suspected and CT scan is negative for blood
- Electroencephalogram if seizures are suspected
Prehospital Stroke Management
Table 4. Stroke Chain of Survival
- Patient or bystander recognition of stroke signs and symptoms
- Immediate activation of 9-1-1 and priority EMS dispatch
- Prompt triage and transport to most appropriate stroke hospital and prehospital notification
- Immediate ED triage to high-acuity area
- Prompt ED evaluation, stroke team activation, laboratory studies, and brain imaging
- Diagnosis and determination of most appropriate therapy. Discussion with patient and family
- Administration of appropriate drugs or other interventions
- Timely admission to stroke unit, intensive care unit, or transfer
Table 5. Prehospital Evaluation and Management of Potential Stroke Patients
- Assess and manage ABCs
- Initiate cardiac monitoring
- Provide supplemental oxygen to maintain O2 saturation >94%
- Establish IV access per local protocol
- Determine blood glucose and treat accordingly
- Do NOT initiate interventions for hypertension unless directed by medical command
- Do NOT administer excessive IV fluids
- Do NOT administer dextrose-containing fluids in nonhypoglycemic patients
- Do NOT administer medications by mouth (maintain NPO)
- Do NOT delay transport for prehospital interventions
Table 6. ED-Based Care
Action and Time
- Door to physician
- ≤10 minutes
- Door to stroke team
- ≤15 minutes
- Door to CT initiation
- ≤25 minutes
- Door to CT interpretation
- ≤45 minutes
- Door to drug (≤80% compliance)
- ≤60 minutes
- Door to stroke unit admission
- ≤3 hours
From Bock BF, Accessed August 23, 2011.
- To increase both the number of patients who are treated and the quality of care, educational stroke programs for physicians, hospital personnel, and EMS personnel are recommended (I-B).
- Activation of the 911 system by patients or other members of the public is strongly recommended (I-B).
Note: 911 Dispatchers should make stroke a priority dispatch, and transport times should be minimized.
- Prehospital care providers should use prehospital stroke
assessment tools, such as the Los Angeles Prehospital Stroke Screen (www.strokecenter.org/wp-content/uploads/2011/08/LAPSS.pdf) or Cincinnati Prehospital Stroke Scale (www.strokecenter.org/wp-content/uploads/2011/08/cincinnati.pdf) (I-B).
- EMS personnel should begin the initial management of stroke in the field, as outlined in Table 5 (I-B).
Note: Development of a stroke protocol to be used by EMS personnel is strongly encouraged.
- Patients should be transported rapidly to the closest available certified primary stroke center or comprehensive stroke center or, if no such centers exist, the most appropriate institution that provides emergency stroke care (I-A).
Note: In some instances, this may involve air medical transport and hospital bypass.
- EMS personnel should provide prehospital notification to the
receiving hospital that a potential stroke patient is en route so
that the appropriate hospital resources may be mobilized before patient arrival (I-B).
Designation of Stroke Centers and Stroke Care
Quality Improvement Process
- Regional systems of stroke care should be developed. These should consist of:
- Health care facilities that provide initial emergency care including administration of IV rtPA, including PSCs, CSCs and other facilities
- Centers capable of performing endovascular stroke treatment with comprehensive peri-procedural care, including CSC and other health care facilities, to which rapid transport can be arranged when appropriate (I-A). (Revised from 2013 guideline)
- It may be useful for PSCs and other health care facilities that provide initial emergency care including administration of IV rtPA to develop the capability of performing emergency noninvasive intracranial vascular imaging to most appropriately select patients for transfer for endovascular intervention and reduce time to endovascular treatment (IIb-C). (Revised from 2013 guideline)
- Endovascular therapy requires the patient to be at an experienced stroke center with rapid access to cerebral angiography and qualified neuro-interventionalists. Systems should be designed, executed and monitored to emphasize expeditious assessment and treatment. Outcomes on all patients should be tracked. Facilities are encouraged to define criteria that can be used to credential individuals who can perform safe and timely IA revascularization procedures (I-E). (Revised from 2013 guideline)
- The creation of primary stroke centers is recommended (I-B).
Notes: The organization of such resources will depend on local resources. The stroke system design of regional acute stroke-ready hospitals and primary stroke centers that provide emergency care and that are closely associated with a comprehensive stroke center, which provides more extensive care, has considerable appeal.
- Certification of stroke centers by an independent external body, such as The Joint Commission or state health department, is recommended (I-B).
Note: Additional medical centers should seek such certification.
- Healthcare institutions should organize a multidisciplinary quality improvement committee to review and monitor stroke care quality benchmarks, indicators, evidence-based practices, and outcomes (I-B).
Notes: The formation of a clinical process improvement team and the establishment of a stroke care data bank are helpful for such quality of care assurances. The data repository can be used to identify the gaps or disparities in quality stroke care. Once the gaps have been identified, specific interventions can be initiated to address these gaps or disparities.
- For patients with suspected stroke, EMS should bypass hospitals that do not have resources to treat stroke and go to the closest facility most capable of treating acute stroke (I-B).
- For sites without in-house imaging interpretation expertise, teleradiology systems approved by the Food and Drug Administration (FDA) (or equivalent organization) are recommended for timely review of brain computed tomography (CT) and magnetic resonance imaging (MRI) scans in patients with suspected acute stroke (I-B).
- When implemented within a telestroke network, teleradiology systems approved by the FDA (or equivalent organization) are useful in supporting rapid imaging interpretation in time for fibrinolysis decision making (I-B).
- The development of comprehensive stroke centers is recommended (I-C).
- Implementation of telestroke consultation in conjunction with stroke education and training for healthcare providers can be useful to increase the use of intravenous (IV) recombinant tissue-type plasminogen activator (rtPA) at community hospitals without access to adequate onsite stroke expertise (IIa-B).
- The creation of acute stroke-ready hospitals can be useful (IIa-C).
Notes: As with primary stroke centers, the organization of such resources will depend on local resources. The stroke system design of regional acute stroke-ready hospitals and primary stroke centers that provide emergency care and that are closely associated with a comprehensive stroke center, which provides more extensive care, has considerable appeal.
Emergency Evaluation and Diagnosis of Acute Ischemic Stroke
- An organized protocol for the emergency evaluation of patients with suspected stroke is recommended (I-B).
Notes: The goal is to complete an evaluation and to begin fibrinolytic treatment within 60 minutes of the patient’s arrival in an emergency department (ED). Designation of an acute stroke team that includes physicians, nurses, and laboratory/radiology personnel is encouraged. Patients with stroke should have a careful clinical assessment, including neurological examination.
- The use of a stroke rating scale, preferably the National Institutes of Health Stroke Scale (NIHSS – Table 2), is recommended (I-B).
- A limited number of hematologic, coagulation, and biochemistry tests are recommended during the initial emergency evaluation, and only the assessment of blood glucose must precede the initiation of IV rtPA (Table 3) (I-B).
- Baseline electrocardiogram assessment is recommended in patients presenting with acute ischemic stroke but should not delay initiation of IV rtPA (I-B).
- Baseline troponin assessment is recommended in patients presenting with acute ischemic stroke but should not delay initiation of IV rtPA (I-C).
- The usefulness of chest radiographs in the hyperacute stroke setting in the absence of evidence of acute pulmonary, cardiac, or pulmonary vascular disease is unclear. If obtained, they should not unnecessarily delay administration of fibrinolysis (IIb-B).
Early Diagnosis: Brain and Vascular Imaging
For patients with acute cerebral ischemic symptoms that have not yet resolved:
- Emergency imaging of the brain is recommended before initiating any specific therapy to treat acute ischemic stroke (I-A).
Notes: In most instances, non–contrast-enhanced CT will provide the necessary information to make decisions about emergency management.
- Either non–contrast-enhanced CT or MRI is recommended before IV rtPA administration to exclude intracerebral hemorrhage (absolute contraindication) and to determine whether CT hypodensity or MRI hyperintensity of ischemia is present (I-A).
- IV fibrinolytic therapy is recommended in the setting of early ischemic changes (other than frank hypodensity) on CT, regardless of their extent (I-A).
- A noninvasive intracranial vascular study is strongly recommended during the initial imaging evaluation of the acute stroke patient if either intra-arterial fibrinolysis or mechanical thrombectomy is being considered for management but should not delay IV rtPA if indicated (I-A).
- In IV fibrinolysis candidates, the brain imaging study should be interpreted within 45 minutes of patient arrival in the ED by a physician with expertise in reading CT and MRI studies of the brain parenchyma (I-C).
- CT perfusion and MRI perfusion and diffusion imaging, including measures of infarct core and penumbra, may be considered for the selection of patients for acute reperfusion therapy beyond the time windows for IV fibrinolysis (IIb-B).
Note: These techniques provide additional information that may improve diagnosis, mechanism, and severity of ischemic stroke and allow more informed clinical decision making.
- Frank hypodensity on non–contrast-enhanced CT may increase the risk of hemorrhage with fibrinolysis and should be considered in treatment decisions. If frank hypodensity involves more than one third of the middle cerebral artery territory, IV rtPA treatment should be withheld (III-A).
For patients with cerebral ischemic symptoms that have resolved:
- Noninvasive imaging of the cervical vessels should be performed routinely as part of the evaluation of patients with suspected TIAs (I-A).
- Noninvasive imaging by means of CT angiography or magnetic resonance angiography of the intracranial vasculature is recommended to exclude the presence of proximal intracranial stenosis and/or occlusion (I-A) and should be obtained when knowledge of intracranial steno-occlusive disease will alter management.
Note: Reliable diagnosis of the presence and degree of intracranial stenosis requires the performance of catheter angiography to confirm abnormalities detected with noninvasive testing.
- Patients with transient ischemic neurological symptoms should undergo neuroimaging evaluation within 24 hours of symptom onset or as soon as possible in patients with delayed presentations (I-B).
Note: MRI, including diffusion-weighted imaging, is the preferred brain diagnostic imaging modality. If MRI is not available, head CT should be performed.