Page 2396 - Hematology_ Basic Principles and Practice ( PDFDrive )

2138 Part XII Hemostasis and Thrombosis

TABLE Eligibility Criteria for Acute Thrombolysis in Acute 0.76–0.98) and death or dependency at one year (OR, 0.82; 95%
145.2 Ischemic Stroke CI, 0.73–0.92) independent of age, sex, or stroke severity. Organized
stroke care is associated with improved outcome for a number of
Eligibility Criteria reasons, including a reduced risk of medical complications such as
Diagnosis of ischemic stroke causing measurable neurological deficit deep vein thrombosis (caused by earlier mobilization), as well as a
The neurological signs should not be minor and isolated. Caution reduced risk of aspiration pneumonia, fever, urinary tract infection,
should be exercised in treating a patient with major deficits falls, and delirium. Prompt evaluation of swallowing function and
Onset of symptoms <4.5 hours before beginning treatment compliance with speech pathology safe swallowing guidelines help to
The neurologic signs should not be clearing spontaneously reduce the risk of aspiration pneumonia in patients with stroke.
The symptoms of stroke should not be suggestive of subarachnoid
hemorrhage
The patient or family members should understand the potential risks Blood Pressure in Acute Stroke
and benefits from treatment
Contraindications for Thrombolysis Although hypertension is the most important risk factor for both
Evidence of intracranial hemorrhage on CT ischemic and hemorrhagic stroke, the optimal approach to managing
Head trauma or prior stroke in previous 3 months blood pressure in the acute setting remains uncertain. A number of
Myocardial infarction in the previous 3 months randomized controlled trials have evaluated acute blood pressure
Gastrointestinal or urinary tract hemorrhage in previous 21 days lowering in acute ischemic stroke, and meta-analyses of these trials
Arterial puncture at a noncompressible site in the previous 7 days reports no benefit of lowering blood pressure in acute phase of
Major surgery in the previous 14 days ischemic stroke, and current AHA guidelines recommend cautious
History of previous intracranial hemorrhage introduction of antihypertensive therapy in those with an initial
Elevated blood pressure (systolic >185 mmHg and diastolic blood pressure >220/120 mmHg, unless there is an alternate indica-
>110 mmHg) tion for blood pressure lowering or the patient has received throm-
Evidence of active bleeding or acute trauma (fracture) on examination bolytic therapy (target <180/105 mmHg). The INTERACT-II phase
Taking an oral anticoagulant or, if taking anticoagulant, INR ≥1.7 is a III trial enrolled patients with spontaneous ICH within 6 hours of
contraindication symptom onset and systolic blood pressure between 150 and
If receiving heparin in previous 48 hours, aPTT must be in normal 220 mmHg. There was no difference in the risk of death or major
range. disability between patients randomized to intensive treatment (target
Platelet count ≤100 000 mm 3 systolic blood pressure <140 mmHg) compared with current
Blood glucose concentration ≥50 mg/dL (2.7 mmol/L) guideline-recommended treatment (target systolic blood pressure
Seizure with postictal residual neurologic impairments <180 mmHg), although it was safe and an ordinal analysis of func-
CT shows a multilobar infarction (hypodensity >1/3 cerebral tional outcome (modified Rankin score) suggested improved func-
hemisphere) tional outcomes with a blood pressure target of <140 mmHg. In the
aPTT, Activated partial thromboplastin time; CT, computed tomography; ATACH phase III trial of patients with ICH within 4.5 hours of
INR, international normalized ratio. symptom onset, an acute blood pressure-lowering target of
110–139 mmHg was not superior to a target of 140–179 mmHg for
reduction in death and disability. The recent ENOS trial reported no
interventional neuroradiology has been a major limitation to the use difference in the risk of disability at 90 days between patients ran-
of this intervention and it has not yet been evaluated in large-scale domized to early (within 48 hours) blood pressure lowering after
clinical trials. acute stroke versus no early intervention, or between patients ran-
domized to continuation of home antihypertensives versus cessation
of home medications in the acute period.
Mechanical Thrombectomy
The MR-CLEAN, ESCAPE, SWIFT PRIME, and EXTEND IA Antithrombotic Therapy in Acute Ischemic Stroke
trials demonstrated the benefit of early intraarterial mechanical throm-
bectomy compared with intravenous thrombolysis alone in patients Based on the results of two large randomized controlled trials, the
with acute ischemic stroke caused by large proximal artery occlusion International Stroke Trial (IST) and the Chinese Acute Stroke Trial
meeting the following criteria: (1) small infarct size with no evidence (CAST), aspirin reduces the risk of recurrent stroke and death in
of hemorrhage on baseline CT of brain; (2) evidence of proximal patients with acute ischemic stroke. In general, therapeutic parenteral
large-artery occlusion in the anterior circulation on vessel imaging anticoagulant therapy is not indicated in acute ischemic stroke, with
(e.g., CT angiography); (3) symptom onset within the past 6–12 hours the exception of cerebral vein thrombosis. Therapeutic heparin is
(three of the trials utilized a 6-hour cut-off and most of the patients in commonly used in patients with acute ischemic stroke and extracra-
ESCAPE were enrolled within the 6-hour window); (4) rapid access nial carotid or vertebral artery dissection, or symptomatic extracranial
to a stroke center with necessary expertise in use of second-generation vertebral or carotid artery atherosclerotic stenosis with crescendo
stent retriever devices. Compared with intravenous thrombolysis TIAs. However, there is limited evidence to guide clinical decision-
alone, intraarterial treatment resulted in significantly higher rates of making on optimal antithrombotic therapy in these patients. The
functional independence at 90 days in all four trials, with no significant recent CADISS trial, which included 250 patients with symptomatic
difference in the risk of symptomatic ICH or death between treatment carotid and vertebral artery dissection, reported no difference in the
groups. The number needed to treat for one additional person to reach risk of recurrent stroke or death between patients randomized to
functional independence ranged from 3 to 7.5. antiplatelet and anticoagulant therapy. However, limitations of this
study included the failure to confirm a diagnosis of dissection in 20%
of participants along with very low rates of recurrent stroke.
Acute Stroke Unit

Organized stroke unit (OSU) care in a dedicated, geographically Carotid Endarterectomy and Stenting
identified ward with multidisciplinary teams that exclusively manage
patients with stroke is associated with improved outcomes in patients The European Carotid Surgery Trial (ECST) and the North American
with acute stroke. A meta-analysis of 26 trials (n = 5592) investigating Symptomatic Carotid Endarterectomy Trial (NASCET) are the largest
OSU care reported a reduction in death (OR, 0.86; 95% CI, trials to evaluate carotid endarterectomy (CEA) in patients with recent