Overview of Stroke

Initial symptoms of stroke occur suddenly. Symptoms depend on the location of infarction (see figure Areas of the brain by function Areas of the brain by function ).

Thus, symptoms can include numbness, weakness of limbs or face; aphasia; confusion; visual disturbances in one or both eyes (eg, transient monocular blindness, diplopia Diplopia Diplopia is the perception of 2 images of a single object. Diplopia may be monocular or binocular. Monocular diplopia is present when only one eye is open. Binocular diplopia disappears when... read more ); dizziness or loss of balance and coordination; and headache.

Neurologic deficits are used to determine the location of stroke (see table Selected Stroke Syndromes Selected Stroke Syndromes ). Anterior circulation stroke typically causes unilateral symptoms. Posterior circulation stroke can cause unilateral or bilateral deficits and is more likely to affect consciousness, especially when the basilar artery is involved.

Systemic or autonomic disturbances (eg, hypertension, fever) occasionally occur.

Other manifestations, rather than neurologic deficits, often suggest the type of stroke. For example,

Evaluation aims to establish the following:

Stroke is suspected in patients with any of the following:

When stroke is suspected, clinicians may use standardized criteria to grade severity and follow changes over time. This approach can be particularly useful as an outcome measure in efficacy studies. The National Institutes of Health Stroke Scale (NIHSS) is often used. It is a 15-item scale to evaluate the patient's level of consciousness and language function and to identify motor and sensory deficits by asking the patient to answer questions and to perform physical and mental tasks. It is also useful for choosing appropriate treatment and predicting outcome.

Stabilization may need to precede complete evaluation. Comatose or obtunded patients (eg, Glasgow Coma Score ≤ 8) may require airway support Overview of Mechanical Ventilation Mechanical ventilation can be Noninvasive, involving various types of face masks Invasive, involving endotracheal intubation Selection and use of appropriate techniques require an understanding... read more . If increased intracranial pressure is suspected, intracranial pressure monitoring Intracranial Pressure (ICP) Monitoring Some monitoring of critical care patients depends on direct observation and physical examination and is intermittent, with the frequency depending on the patient’s illness. Other monitoring... read more and measures to reduce cerebral edema Increased intracranial pressure Traumatic brain injury (TBI) is physical injury to brain tissue that temporarily or permanently impairs brain function. Diagnosis is suspected clinically and confirmed by imaging (primarily... read more may be necessary.

Specific acute treatments vary by type of stroke. They may include reperfusion Acute stroke treatment (eg, IV thrombolysis, mechanical thrombectomy) for some ischemic strokes.

Providing supportive care, correcting coexisting abnormalities (eg, fever, hypoxia, dehydration, hyperglycemia, sometimes hypertension), and preventing and treating complications are vital during the acute phase and convalescence (see table Strategies to Prevent and Treat Stroke Complications Strategies to Prevent and Treat Stroke Complications ); these measures clearly improve clinical outcomes (1 Treatment reference Strokes are a heterogeneous group of disorders involving sudden, focal interruption of cerebral blood flow that causes neurologic deficit. Strokes can be Ischemic (80%), typically resulting... read more ). During convalescence, measures to prevent aspiration Prevention Aspiration pneumonitis and pneumonia are caused by inhaling toxic and/or irritant substances, most commonly large volumes of upper airway secretions or gastric contents, into the lungs. Chemical... read more , deep venous thrombosis Deep Venous Thrombosis (DVT) Prevention It is preferable and safer to prevent deep venous thrombosis (DVT) than to treat it, particularly in high-risk patients. DVT prophylaxis begins with risk assessment. Risk, along with other factors... read more , urinary tract infections Prevention Bacterial urinary tract infections (UTIs) can involve the urethra, prostate, bladder, or kidneys. Symptoms may be absent or include urinary frequency, urgency, dysuria, lower abdominal pain... read more , pressure ulcers Pressure Injuries A hospital may provide emergency medical care, diagnostic testing, intensive treatment, or surgery, which may or may not require admission. Older patients use hospitals more than younger patients... read more , and undernutrition Undernutrition A hospital may provide emergency medical care, diagnostic testing, intensive treatment, or surgery, which may or may not require admission. Older patients use hospitals more than younger patients... read more may be necessary. Passive exercises, particularly of paralyzed limbs, and breathing exercises are started early to prevent contractures, atelectasis, and pneumonia.

After a stroke, most patients require rehabilitation Stroke Rehabilitation Rehabilitation after stroke aims to preserve or improve range of motion, muscle strength, bowel and bladder function, and functional and cognitive abilities. Specific programs are based on the... read more (occupational and physical therapy) to maximize functional recovery. Some need additional therapies (eg, speech therapy Speech Therapy Speech therapists can identify the most effective methods of communication for patients who have aphasia, dysarthria, or verbal apraxia or who have had a laryngectomy: Expressive aphasia: A... read more , feeding restrictions). For rehabilitation, an interdisciplinary approach is best.

Depression after stroke may require antidepressants; many patients benefit from counseling.

Modifying risk factors through lifestyle changes (eg, stopping cigarette smoking) and medications (eg, for hypertension) can help delay or prevent subsequent strokes. Other stroke prevention strategies are chosen based on the patient's risk factors. For ischemic stroke prevention Long-term stroke treatment , strategies may include procedures (eg, carotid endarterectomy, stent placement), antiplatelet therapy, and anticoagulation.

The sooner a stroke is treated, the less severe brain damage is likely to be and the better the chances for recovery.

Certain factors suggest a poor outcome. Strokes that impair consciousness or that affect a large part of the left side of the brain may be particularly grave.

Usually, the more quickly patients improve during the days after stroke, the more they will ultimately improve. Improvement commonly continues for 6 to 12 months after the stroke. In adults who have had an ischemic stroke, problems that remain after 12 months are likely to be permanent, but children continue to improve slowly for many months. Older people fare less well than younger people. For people who already have other serious disorders (eg, dementia), recovery is more limited. Of all the different causes of strokes, lacunar strokes have the best prognosis.

If a hemorrhagic stroke is not massive and intracranial hypertension is absent the outcome is likely to be better than that after an ischemic stroke with similar symptoms. Blood (in a hemorrhagic stroke) does not damage brain tissue as much as ischemia does.