2 Cerebrovascular Emergency—Acute Stroke Diagnosis and Management



Maria Carissa C. Pineda, Sridhara S. Yaddanapudi, and Norman Ajiboye


Abstarct


Stroke is one of the leading causes of disability in the USA. Timely acute interventions in the form of tPA and endovascular therapy have changed the landscape of acute stroke care. Having an organized and efficient system of care is extremely important for delivering acute stroke care. This chapter details the components of acute stroke care from the emergency room to the neurocritical care unit. The chapter covers pre- and post-tPA and endovascular care as well as post stroke complication management in the neurocritical care unit.




2 Cerebrovascular Emergency—Acute Stroke Diagnosis and Management



2.1 Epidemiology




  • Stroke is the fifth leading cause of death in North America



  • It is the leading cause of disability



  • 795,000 people/year have a stroke in North America



2.2 Etiology



2.2.1 Nonmodifiable Risk Factors




  • Age



  • Sex



  • Race



  • Family history



2.2.2 Modifiable Risk Factors




  • Hypertension



  • Diabetes mellitus



  • Hyperlipidemia



  • Smoking



  • Excessive alcohol use



  • Obstructive sleep apnea



2.2.3 Stroke Subtypes


According to TOAST 9 classification there are five subtypes of ischemic stroke:




  1. Large artery atherosclerosis



  2. Cardioembolism



  3. Small vessel occlusion (lacunar stroke)



  4. Stroke of other determined etiology




    • Mechanical valves



    • Atrial fibrillation/flutter



    • Left atrial (LA) appendage thrombus



    • Left ventricular (LV) thrombus



    • Recent myocardial infarction (MI)



    • Dilated cardiomyopathy



    • Endocarditis/infection



    • Patent foramen ovale



    • Atrial septal aneurysm



    • Congestive heart failure



    • Vasculopathies



    • Hypercoagulable state



  5. Stroke of undetermined etiology/cryptogenic



2.3 Common Clinical Presentations


Presentation depends on the vascular territory. See Table 2‑1.


























Table 2.1 Common clinical presentation by vascular territory

Vascular territory


Symptoms


Middle cerebral artery


Contralateral facial droop, weakness and sensory loss (arm > leg), aphasia, neglect, contralateral homonymous hemianopia, ipsilateral gaze deviation



Anterior cerebral artery


Contralateral hemiplegia (leg >> face and arm), abulia, rigidity, gait apraxia, urinary incontinence


Posterior cerebral artery


Contralateral homonymous hemianopia, alexia, contralateral sensory loss, cortical blindness, visual hallucinations, optic ataxia, gaze apraxia



Subcortical


Contralateral hemiplegia or hemisensory loss (usually face = arm = leg), no cortical features (aphasia, neglect), thalamic strokes may have aphasia, delirium, other cortical features



Basilar artery


Cranial nerve palsy, crossed sensory deficits, dizziness, diplopia, dysarthria, dysphagia, vertigo, nausea/vomiting, hiccups, contralateral weakness, ataxia, nystagmus, coma




F.A.S.T. is the acronym most associated with recognition of early stroke signs:


F = Facial weakness


A = Arm weakness


S = Speech difficulty


T = Time to call 9–1-1


Once in the emergency department a more thorough examination using the National Institutes of Health Stroke Scale (NIHSS) is completed (Table 2‑2).



2.4 Differential Diagnosis for Acute Ischemic Stroke




  • Intracerebral hemorrhage (ICH)



  • Subarachnoid hemorrhage (SAH)



  • Migraine with aura (most auras DO NOT last beyond 60 minutes nor present with loss of function)



  • Transient global amnesia



  • Postictal Todd’s palsy (history of epilepsy or prior Todd’s palsy, short duration with improvement)



  • Hypoglycemia (rapid improvement with glucose correction) 2



2.5 Acute Stroke Diagnosis, Treatment, and Management


4



2.5.1 Stroke Activation


(Fig. 2‑1)




  • ABC: airway, breathing, circulation




    • O2 saturation >94% (supplemental oxygen is not recommended if the patient is not hypoxic)



    • Finger-stick glucose should be >50



  • Intravenous (IV) access



  • History: Past medical, surgical, and medication (ask about antiplatelet and anticoagulant agents)



  • Check electrocardiogram (ECG)—rule out acute ST-elevation myocardial infarction (STEMI)



  • Send STAT labs: Coagulation panel and platelet



  • Perform focal stroke examination using NIHSS (Table 2‑2 and Fig. 2‑1 shows the pictures and sentences used for questions 9 and 10 on the scale.)



  • Check STAT computed tomography (CT) of head ( Fig. 2‑2 )




    • Rule out hemorrhage



    • Rule out large completed ischemic stroke



    • Identify acute middle cerebral artery (MCA) or basilar occlusion



  • Assess eligibility for IV tPA (Table 2‑3 and Fig. 2‑3)




    • If eligible, dosing for tPA is 0.9 mg/kg with a maximum dose of 90 mg.



    • A bolus of 10% is given over the first minute followed by the remaining dose over 1 hour.



    • If a patient is ineligible for tPA then administer 325 mg aspirin orally or 300 mg aspirin rectally (provided no hemorrhage on CT of head).



  • Blood pressure goals (Fig. 2‑4):




    • Blood pressure must be controlled prior to administering IV tPA to minimize the bleeding risk. Goal is <185/110.



    • With tPA administration, maintain a blood pressure (BP) goal of <180/105.



    • If tPA is NOT given then the BP goal should be < 220/110 during the first 24 hours.



    • Avoid agents like hydralazine, nitroprusside, and nitroglycerin due to their vasodilatory effect.



  • Fig. 2‑1 outlines the pathway for further imaging in patients with suspected large vessel occlusion or dense vessel on plain CT head. CT angiogram (CTA) of head and neck to identify artery occlusion and CT perfusion to evaluate size of core infarct and penumbra (Fig. 2‑5).

Fig. 2.1 Thomas Jefferson University acute stroke algorithm for in-house and emergency room activation.
Fig. 2.2 (a, b) Examples of a dense occlusion of an artery due to acute thrombus: (a) Dense occluded right middle cerebral artery (MCA). (b) Dense occluded basilar artery. (c, d) Examples of computed tomography (CT)scan finding that would exclude a patient from receiving intravenous (IV) tPA. (c) A completed right middle cerebral artery (MCA) stroke. (d) A right thalamic hemorrhage.
Fig. 2.3 Thomas Jefferson University Algorithm for Ischemic Stroke and Assessment for intravenous tPA (Alteplase).
Fig. 2.4 Thomas Jefferson University algorithm for the management of hypertensive emergency in patients with acute ischemic stroke.
Fig. 2.5 Advanced imaging obtained for patients suspected of large vessel occlusions. (a) Computed tomography (CT) angiogram demonstrating occlusion of the right middle cerebral artery with a “cutoff” of contrast. (b, c) Represent CT perfusion images. (b) Cerebral blood flow showing decreased flow within the right basal ganglia. (c) Mean transit time (MTT) demonstrating prolonged perfusion time. MTT helps to distinguish tissue “at risk” (penumbra) from ischemic nonviable tissue.















































































Table 2.2 (a) NIH stroke scale. (b) Supplement to questions 9 and 10 on the National Institutes of Health Stroke Scale (NIHSS) used to determine deficits in language and speech. (1–3) Assessment of aphasia: (1) describing the picture, (2) reading the short sentences, and (3) naming the objects listed. (4) Words repeated by the patient to assess dysarthria. (Reproduced with permission from National Institute of Neurological Disorders and Stroke (NINDS).)

NIH Stroke Scale


Category


Description


Score



1a. Level of consciousness (LOC)


0 = Alert


1 = Drowsy


2 = Stuporous


3 = Coma



1b. LOC questions


0 = Answers both correctly


1 = Answers one correctly


2 = Answers neither correctly



2. Best gaze


0 = Normal


1 = Partial gaze palsy


2 = Forced deviation



3. Visual


0 = No visual loss


1 = Partial hemianopia


2 = Complete hemianopia


3 = Bilateral hemianopia



4. Facial palsy


0 = No facial palsy


1 = Minor facial palsy


2 = Partial facial palsy


3 = Complete facial palsy



5a. Motor left arm


0 = No drift


1 = Drift


2 = Can’t resist gravity


3 = No effort against gravity


4 = No movement


UN = Amputation/Joint fusion



5b. Motor right arm


0 = No drift


1 = Drift


2 = Can’t resist gravity


3 = No effort against gravity


4 = No movement


UN = Amputation/Joint fusion



6a. Motor left leg


0 = No drift


1 = Drift


2 = Can’t resist gravity


3 = No effort against gravity


4 = No movement


UN = Amputation/Joint fusion



6b. Motor right leg


0 = No drift


1 = Drift


2 = Can’t resist gravity


3 = No effort against gravity


4 = No movement


UN = Amputation/Joint fusion



7. Limb ataxia


0 = Absent


1 = Present in one limb


2 = Present in two limbs



8. Sensory


0 = Normal


1 = Partial loss


2 = Severe loss



9. Best languagea


0 = No aphasia


1 = Mild to moderate aphasia


2 = Severe aphasia


3 = Mute



10. Dysarthriab


0 = Normal articulation


1 = Mild to moderate dysarthria


2 = Near to unintelligible


3 = Intubated or other barrier



11. Extinction and inattention


0 = No neglect


1 = Partial neglect


3 = Complete neglect




Total



See Fig. 2.1 aAsk patient to name items, describe the picture, read a sentence, intubated patients should write response if able.


bEvaluate speech clarity by asking patient to repeat the listed words


Abbreviations: LOC, level of consciousness NIHSS, National Institute of Health Stroke Scale.















































































































Table 2.3 Eligibility criteria, warnings, and contraindications to intravenous tPA (Alteplase)

Criteria for the use of intravenous tPA (Alteplase)


Eligibility criteria within the 3 hours window




Recommended for both severe stroke and for mild but disabling strokes



Age ≥ 18 years; equally recommended for ages < 80 and >80 years under 3 hours of onset


Warnings for IV tPA within the 3 hours window




Clinical syndrome not consistent with ischemic stroke



Recent history of intracranial hemorrhage


Contraindications for IV tPA within the 3 hours window




Active intracranial hemorrhage (i.e., subdural hematoma, epidural hematoma, subarachnoid hemorrhage, or spontaneous intracerebral hemorrhage)



Active internal bleeding



Clinical presentation suggesting cerebral aneurysm rupture and/or subarachnoid hemorrhage



Delay in patient arrival, unknown time of onset and/or “wake up” stroke



Current severe uncontrolled hypertension (SBP > 185 mm Hg or DBP > 110 mm Hg) despite aggressive treatment



Presence of intracranial conditions that may increase the risk of bleeding (neoplasm either primary or metastatic; cerebral arteriovenous malformation, etc.)



Ischemic stroke in the setting of infective endocarditis



Recent intracranial or intraspinal surgery within prior 3 months (lumbar puncture within 7 days does NOT apply)



Recent severe head trauma or history of post-traumatic stroke within 3 months



History of structural gastrointestinal malignancy or recent gastrointestinal hemorrhage within 3 weeks



Known or suspected aortic dissection



Bleeding diathesis/coagulopathy or thrombocytopenia including but not limited to:




  • Known INR > 1.7 and/or elevated PT > 15 seconds



  • Known administration of therapeutic doses of heparin or low-molecular-weight heparin within 24 hours of presentation or elevated aPTT >40 seconds



  • Known platelet count < 100,000/mm3



  • Known use of direct thrombin inhibitors or factor Xa inhibitors (BOACs) within 48 hours of stroke symptoms assuming normal renal function


Eligibility criteria for the 3 to 4.5 hours window




Age <80 years



NO history of both stroke and diabetes mellitus



NIHSS < 25



Not on oral anticoagulant agents



No evidence of ischemia of > 1/3 of the MCA territory


Additional warnings within the 3 to 4.5 hours window*




Age >80 years



History of prior stroke and diabetes mellitus



NIHSS >25


Additional contraindications within the 3 to 4.5 hours window




Current use of oral anticoagulant and/or INR > 1.7



Patients with imaging evidence of ischemic injury involving more than one-third of the MCA territory


*Deemed Class IIb (possible benefit > risk) so it may be considered.


Adapted from the AHA/ASA 2018 Guideline for the Early Management of Acute Ischemic Stroke 3


Abbreviations: aPTT, activated partial thromboplastin time; DBP, diastolic blood pressure; INR, international normalized ratio; MCA, middle cerebral artery; NIHSS; PT, prothrombin time; SBP, systolic blood pressure.


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Feb 6, 2021 | Posted by in NEUROLOGY | Comments Off on 2 Cerebrovascular Emergency—Acute Stroke Diagnosis and Management

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