Management of the Acute Stroke Patient

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Management of the Acute Stroke Patient
Immediate Laboratory Studies in the Acute Stroke Patient
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Noncontrast CT or MRI of the brain
Electrocardiogram
CBC including platelets
Cardiac enzymes including troponin levels
Electrolytes, BUN, creatinine and glucose
Prothrombin time and international normalized ratio (INR)
Oxygen saturation
Lipid Profile
Other studies may be appropriate in select patients and include:
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Liver function tests
Toxicology screen
Blood alcohol level
Pregnancy test (in women of child bearing age)
Arterial Blood Gas (if hypoxia is present)
Lumbar Puncture (if subarachnoid pressure is suspected and CT is negative for blood)
Electroencephalogram (if seizures are suspected).
Use of Intravenous Fibrinolytic (Thrombolytic) therapy in Acute Ischemic Stroke
Treatment timeline — "Time is brain": the sooner intravenous rTPA (altepase) treatment is
initiated after ischemic stroke, the more likely it is to be beneficial. Eligible patients should be
treated as quickly as possible within the appropriate 3 or 4.5 hour time limit. To achieve the
earliest treatment, current guidelines recommend that the elapsed time to the start of
alteplase infusion should be ≤60 minutes from the time of patient arrival in the emergency
department. The following in-hospital timeline is suggested as a goal for all patients with acute
ischemic stroke who are eligible for treatment with intravenous altepase:
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Evaluation by physician - 10 minutes
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Stroke or neurologic expertise contacted, ie, stroke team - 15 minutes
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Head CT or MRI scan - 25 minutes
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Interpretation of neuroimaging scan - 45 minutes
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Start of treatment - 60 minutes from arrival
In-hospital treatment delay can occur with any of these steps. Other items that can lead to
inordinate delay include initial telephone triage by the stroke physician, obtaining and waiting
for results of blood and laboratory tests, obtaining consent, and delivery of Altepase (rTPA)
from the pharmacy to the bedside.
Informed consent
Whether to proceed to thrombolysis in an individual patient should be based upon a discussion
of the risks and benefits with the patient and family if possible. However, neurologic deficits
caused by acute stroke often preclude obtaining informed consent from the patient. Altepase
is an approved therapy for acute stroke; consent is not required to administer alteplase as an
emergent therapy for eligible patients if surrogate consent is not possible.
Indications and Contraindications for rTPA use in acute stroke
Intravenous administration of rTPA is the only FDA-approved medical therapy for treatment of
patients with acute ischemic stroke. Its use is associated with improved outcomes for a broad
spectrum of patients who can be treated within 3 hours of stroke onset. Earlier treatment (ie,
within 90 minutes) may be more likely to result in a favorable outcome. Later treatment, at 90
to 180 minutes, also is beneficial. Patients with major strokes (NIHSS score >22) have a very
poor prognosis, but some positive treatment effect with rTPA has been documented. Because
the risk of hemorrhage is considerable among patients with severe deficits, the decision to treat
with rTPA should be made with caution. Treatment with rTPA is associated with symptomatic
intracranial hemorrhage, which may be fatal. In the original NINDS trials, the risk of
symptomatic bleeding was ≈6%. Recent community-based studies and registries report lower
rates of hemorrhage. *(Guidelines for the Early Management of Adults with Ischemic Stroke.
Stroke. 2007; 38: 1655-1711)
The American Heart Association/American Stroke Association (AHA/ASA) inclusion guidelines
for the administration of rTPA in under 3 hours are as follows :
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Diagnosis of ischemic stroke causing measurable neurologic deficit
Neurologic signs not clearing spontaneously
Neurologic signs not minor and isolated
Symptoms not suggestive of subarachnoid hemorrhage
Onset of symptoms less than 3 hours before beginning treatment
No head trauma or prior stroke in past 3 months
No MI in prior 3 months
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No GI/GU hemorrhage in previous 21 days
No arterial puncture in noncompressible site during prior 7 days
No major surgery in prior 14 days
No history of prior intracranial bleed
Systolic blood pressure under 185 mm Hg, diastolic blood pressure under 110 mm Hg
No evidence of acute trauma or bleeding
Not taking an oral anticoagulant, or if so, INR under 1.7
If taking heparin within 48 hours, a normal activated prothrombin time (aPT)
Platelet count of more than 100,000/μL
Blood glucose greater than 50 mg/dL (2.7 mmol)
No seizure with residual postictal impairments
CT scan does not show evidence of multilobar infarction (hypodensity over one-third
hemisphere)
The patient and family understand the potential risks and benefits of therapy
In May 2009, the AHA/ASA guidelines for the administration of rTPA following acute stroke
were revised to expand the window of treatment from 3 hours to 4.5 hours to provide more
patients with an opportunity to receive benefit from this effective therapy.
Eligibility criteria for treatment in the 3 to 4.5 hours after acute stroke are similar to those for
treatment at earlier time periods, with any 1 of the following additional exclusion criteria:
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Patients older than 80 years
All patients taking oral anticoagulants are excluded regardless of the international
normalized ratio (INR)
Patients with baseline NIHSS score > 25
Patients with a history of stroke and diabetes
Thrombolytic therapy should be withheld for patients with extensive multilobar infarction with
hypodensity involving more than one-third of the cerebral hemisphere on head CT. Minor
ischemic changes (ie, early signs of infarction) on CT are not a contraindication to treatment.
How to give rTPA
Infuse 0.9 mg/kg (maximum dose 90 mg) over 60 minutes with 10% of the dose given as a bolus
over 1 minute.
Admit the patient to an intensive care or stroke unit for monitoring.
Perform neurological assessments every 15 minutes during the infusion and every 30 minutes
thereafter for the next 6 hours, then hourly until 24 hours after treatment.
If the patient develops severe headache, acute hypertension, nausea, or vomiting, discontinue
the infusion (if rTPA is being administered) and obtain emergency CT scan.
Measure blood pressure every 15 minutes for the first 2 hours and subsequently every 30
minutes for the next 6 hours, then hourly until 24 hours after treatment.
Increase the frequency of blood pressure measurements if a systolic blood pressure is ≥180 mm
Hg or if a diastolic blood pressure is ≥105 mm Hg; administer antihypertensive medications to
maintain blood pressure at or below these levels (see Table 10).
Delay placement of nasogastric tubes, indwelling bladder catheters, or intra-arterial pressure
catheters.
Obtain a follow-up CT scan at 24 h before starting anticoagulants or antiplatelet agents
Treatment options for acute ischemic stroke patients who are not candidates for rTPA*
Aspirin reduces the risk of early recurrent ischemic stroke when given within 48 hours of the
onset of stroke but increases the risk of hemorrhagic stroke (absolute risk reduction = 0.7%;
number needed to treat = 143). Overall, for aspirin, there is a slight, but statistically significant
benefit in reducing recurrent stroke. Conversely, unfractionated heparin and LMW
heparin/heparinoids, when used within 48 hours of onset in patients with acute ischemic
stroke, have not been shown to reduce the rate of stroke recurrence.
Recommendations
1. Patients with acute ischemic stroke presenting within 48 hours of symptom onset should be
given aspirin (160 to 325 mg/day) to reduce stroke mortality and decrease morbidity,
provided contraindications such as allergy and gastrointestinal bleeding are absent, and the
patient has or will not be treated with recombinant tissue type plasminogen activator
(Grade A). The data are insufficient at this time to recommend the use of any other platelet
antiaggregant in the setting of acute ischemic stroke.
Other agents
2. Subcutaneous unfractionated heparin, LMW heparins,and heparinoids may be considered
for DVT prophylaxis in at-risk patients with acute ischemic stroke, recognizing that non
pharmacologic treatments for DVT prevention also exist (Grade A). A benefit in reducing the
incidence of PE has not been demonstrated. The relative benefits of these agents must be
weighed against the risk of systemic and intracerebral hemorrhage.
3. Although there is some evidence that fixed-dose, subcutaneous, unfractionated heparin
reduces early recurrent ischemic stroke, this benefit is negated by a concomitant increase in
the occurrence of hemorrhage. Therefore, use of subcutaneous unfractionated heparin is
not recommended for decreasing the risk of death or stroke-related morbidity or for
preventing early stroke recurrence (Grade A).
4. a. Dose-adjusted, unfractionated heparin is not recommended for reducing morbidity,
mortality, or early recurrent stroke in patients with acute stroke (i.e., in the first 48 hours)
because the evidence indicates it is not efficacious and may be associated with increased
bleeding complications (Grade B).
b. High-dose LMW heparin/heparinoids have not been associated with either benefit or
harm in reducing morbidity, mortality, or early recurrent stroke in patients with acute
stroke and are, therefore, not recommended for these goals (Grade A).
*( Anticoagulants and Antiplatelet Agents in Acute Ischemic Stroke
Report of the Joint Stroke Guideline Development Committee of the American Academy of
Neurology and the American Stroke Association (a Division of the American Heart Association))
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