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Aspirin reduces the overall risk of recurrence by 13% with greater benefit early on. Definitive therapy within the first few hours is aimed at removing the blockage by breaking the clot down (thrombolysis), or by removing it mechanically (thrombectomy). The philosophical premise underlying the importance of rapid stroke intervention was summed up as "Time is Brain!" in the early 1990s. Years later, that same idea, that rapid cerebral blood flow restoration results in fewer brain cells dying, has been proved and quantified.
Tight blood sugar control in the first few hours does not improve outcomes and may cause harm. High blood pressure is also not typically lowered as this has not been found to be helpful. Cerebrolysin, a mix of pig brain tissue used to treat acute ischemic stroke in many Asian and European countries, does not improve outcomes and may increase the risk of severe adverse events.
People with intracerebral hemorrhage require supportive care, including blood pressure control if required. People are monitored for changes in the level of consciousness, and their blood sugar and oxygenation are kept at optimum levels. Anticoagulants and antithrombotics can make bleeding worse and are generally discontinued (and reversed if possible). A proportion may benefit from neurosurgical intervention to remove the blood and treat the underlying cause, but this depends on the location and the size of the hemorrhage as well as patient-related factors, and ongoing research is being conducted into the question as to which people with intracerebral hemorrhage may benefit.
In subarachnoid hemorrhage, early treatment for underlying cerebral aneurysms may reduce the risk of further hemorrhages. Depending on the site of the aneurysm this may be by surgery that involves opening the skull or endovascularly (through the blood vessels).
An antiplatelet, such as aspirin, is started for secondary prevention of stroke after most TIAs. An exception is TIAs due to blood clots originating from the heart, in which case anticoagulants are generally recommended. After TIA or minor stroke, aspirin therapy has been shown to reduce the short-term risk of recurrent stroke by 60-70%, and the long-term risk of stroke by 13%.
The typical therapy may include aspirin alone, a combination of aspirin plus extended-release dipyridamole, or clopidogrel alone. Clopidogrel and aspirin have similar efficacies and side effect profiles. Clopidogrel is more expensive and has a slightly decreased risk of GI bleed. There is some evidence that giving both aspirin and clopidogrel within 24 hours of a TIA or minor stroke is more effective than aspirin alone. Another antiplatelet, ticlopidine, is rarely used due to increased side effects.
Treatment for cerebrovascular disease may include medication, lifestyle changes and/or surgery, depending on the cause.
Examples of medications are:
- antiplatelets (aspirin, clopidogrel)
- blood thinners (heparin, warfarin)
- antihypertensives (ACE inhibitors, beta blockers)
- anti-diabetic medications.
Surgical procedures include:
- endovascular surgery and vascular surgery (for future stroke prevention).
Hypothermia treatment induced by head cooling or systemic cooling administered within 6 hours of birth for 72 hours has proven beneficial in reducing death and neurological impairments at 18 months of age. This treatment does not completely protect the injured brain and may not improve the risk of death in the most severely hypoxic-ischemic neonates and has also not been proven beneficial in preterm infants. Combined therapies of hypothermia and pharmacological agents or growth factors to improve neurological outcomes are most likely the next direction for damaged neonatal brains, such as after a stroke.
There are several interventions that are often used to help prevent the recurrence of a watershed stroke; namely, nutritional interventions, as well as antiplatelet, anticoagulant, and statin drug use. Nutritional interventions, including increased consumption of certain amino acids, antioxidants, B-group vitamins, and zinc, have been shown to increase the recovery of neurocognitive function after a stroke. Antiplatelet drugs, such as aspirin, as well as anticoagulants, are used to help prevent blood clots and therefore embolisms, which can cause watershed strokes. Statin drugs are also used to control hyperlipidemia, another risk factor for watershed stroke.
Treatment remains controversial with regards to the risk/benefit ratio, which differs significantly from treatment of stroke in adults. Presence or possibility of organ or limb impairment and bleeding risks are possible with treatments using antithrombotic agents.
Anticoagulants may be started if the TIA is thought to be attributable to atrial fibrillation. Atrial fibrillation is an abnormal heart rhythm that may cause the formation of blood clots that can travel to the brain, resulting in TIAs or ischemic strokes. Atrial fibrillation increases stroke risk by five times, is thought to cause 10-12% of all ischemic strokes in the US. Anticoagulant therapy can decrease the relative risk of ischemic stroke in those with atrial fibrillation by 67% Warfarin is a common anticoagulant used, but direct acting oral anticoagulants (DOACs), such as apixaban, have been shown to be equally effective while also conferring a lower risk of bleeding. Generally, anticoagulants and antiplatelets are not used in combination, as they result in increased bleeding risk without a decrease in stroke risk. However, combined antiplatelet and anticoagulant therapy may be warranted if the patient has symptomatic coronary artery disease in addition to atrial fibrillation.
Sometimes, myocardial infarction (“heart attack”) may lead to the formation of a blood clot in one of the chambers of the heart. If this is thought to be the cause of the TIA, people may be temporarily treated with warfarin or other anticoagulant to decrease the risk of future stroke.
Typically, tissue plasminogen activator may be administered within three to four-and-a-half hours of stroke onset if the patient is without contraindications (i.e. a bleeding diathesis such as recent major surgery or cancer with brain metastases). High dose aspirin can be given within 48 hours. For long term prevention of recurrence, medical regimens are typically aimed towards correcting the underlying risk factors for lacunar infarcts such as hypertension, diabetes mellitus and cigarette smoking. Anticoagulants such as heparin and warfarin have shown no benefit over aspirin with regards to five year survival.
Patients who suffer lacunar strokes have a greater chance of surviving beyond thirty days (96%) than those with other types of stroke (85%), and better survival beyond a year (87% versus 65-70%). Between 70% and 80% are functionally independent at 1 year, compared with fewer than 50% otherwise.
Occupational Therapy and Physical Therapy interventions are used in the rehabilitation of lacunar stroke. A physiotherapy program will improve joint range of motion of the paretic limb using passive range of motion exercises. When increases in activity are tolerated, and stability improvements are made, patients will progress from rolling to side-lying, to standing (with progressions to prone, quadruped, bridging, long-sitting and kneeling for example) and learn to transfer safely (from their bed to a chair or from a wheel chair to a car for example). Assistance and ambulation aids are used as required as the patient begins walking and lessened as function increases. Furthermore, splints and braces can be used to support limbs and joints to prevent complications such as contractures and spasticity. The rehabilitation healthcare team should also educate the patient and their family on common stroke symptoms and how to manage an onset of stroke. Continuing follow-up with a physician is essential so that the physician may monitor medication dosage and risk factors.
Endovascular interventions, including surgical revascularization, can increase blood flow in the area of the stroke, thereby decreasing the likelihood that insufficient blood flow to the watershed regions of the brain will result in subsequent strokes. Neuroscientists are currently researching stem cell transplantation therapies to improve recovery of cebreral tissue in affected areas of the brain post-stroke. Should this intervention be proven effective, it will greatly increase the number of neurons in the brain that can recover from a stroke.
In last decade, similar to myocardial infarction treatment, thrombolytic drugs were introduced in the therapy of cerebral infarction. The use of intravenous rtPA therapy can be advocated in patients who arrive to stroke unit and can be fully evaluated within 3 h of the onset.
If cerebral infarction is caused by a thrombus occluding blood flow to an artery supplying the brain, definitive therapy is aimed at removing the blockage by breaking the clot down (thrombolysis), or by removing it mechanically (thrombectomy). The more rapidly blood flow is restored to the brain, the fewer brain cells die. In increasing numbers of primary stroke centers, pharmacologic thrombolysis with the drug tissue plasminogen activator (tPA), is used to dissolve the clot and unblock the artery.
Another intervention for acute cerebral ischaemia is removal of the offending thrombus directly. This is accomplished by inserting a catheter into the femoral artery, directing it into the cerebral circulation, and deploying a corkscrew-like device to ensnare the clot, which is then withdrawn from the body. Mechanical embolectomy devices have been demonstrated effective at restoring blood flow in patients who were unable to receive thrombolytic drugs or for whom the drugs were ineffective, though no differences have been found between newer and older versions of the devices. The devices have only been tested on patients treated with mechanical clot embolectomy within eight hours of the onset of symptoms.
Angioplasty and stenting have begun to be looked at as possible viable options in treatment of acute cerebral ischaemia. In a systematic review of six uncontrolled, single-center trials, involving a total of 300 patients, of intra-cranial stenting in symptomatic intracranial arterial stenosis, the rate of technical success (reduction to stenosis of <50%) ranged from 90-98%, and the rate of major peri-procedural complications ranged from 4-10%. The rates of restenosis and/or stroke following the treatment were also favorable. This data suggests that a large, randomized controlled trial is needed to more completely evaluate the possible therapeutic advantage of this treatment.
If studies show carotid stenosis, and the patient has residual function in the affected side, carotid endarterectomy (surgical removal of the stenosis) may decrease the risk of recurrence if performed rapidly after cerebral infarction. Carotid endarterectomy is also indicated to decrease the risk of cerebral infarction for symptomatic carotid stenosis (>70 to 80% reduction in diameter).
In tissue losses that are not immediately fatal, the best course of action is to make every effort to restore impairments through physical therapy, cognitive therapy, occupational therapy, speech therapy and exercise.
Preventive measures that can be taken to avoid sustaining a silent stroke are the same as for stroke. Smoking cessation is the most immediate step that can be taken, with the effective management of hypertension the major medically treatable factor.
The goal of treatment is to prevent the development or continuation of neurologic deficits. Treatments include observation, anticoagulation, stent implantation and carotid artery ligation.
Prognostics factors:
Lower Glasgow coma scale score, higher pulse rate, higher respiratory rate and lower arterial oxygen saturation level is prognostic features of in-hospital mortality rate in acute ischemic stroke.
For newborn infants starved of oxygen during birth there is now evidence that hypothermia therapy for neonatal encephalopathy applied within 6 hours of cerebral hypoxia effectively improves survival and neurological outcome. In adults, however, the evidence is less convincing and the first goal of treatment is to restore oxygen to the brain. The method of restoration depends on the cause of the hypoxia. For mild-to-moderate cases of hypoxia, removal of the cause of hypoxia may be sufficient. Inhaled oxygen may also be provided. In severe cases treatment may also involve life support and damage control measures.
A deep coma will interfere with body's breathing reflexes even after the initial cause of hypoxia has been dealt with; mechanical ventilation may be required. Additionally, severe cerebral hypoxia causes an elevated heart rate, and in extreme cases the heart may tire and stop pumping. CPR, defibrilation, epinephrine, and atropine may all be tried in an effort to get the heart to resume pumping. Severe cerebral hypoxia can also cause seizures, which put the patient at risk of self-injury, and various anti-convulsant drugs may need to be administered before treatment.
There has long been a debate over whether newborn infants with cerebral hypoxia should be resuscitated with 100% oxygen or normal air. It has been demonstrated that high concentrations of oxygen lead to generation of oxygen free radicals, which have a role in reperfusion injury after asphyxia. Research by Ola Didrik Saugstad and others led to new international guidelines on newborn resuscitation in 2010, recommending the use of normal air instead of 100% oxygen.
Brain damage can occur both during and after oxygen deprivation. During oxygen deprivation, cells die due to an increasing acidity in the brain tissue (acidosis). Additionally, during the period of oxygen deprivation, materials that can easily create free radicals build up. When oxygen enters the tissue these materials interact with oxygen to create high levels of oxidants. Oxidants interfere with the normal brain chemistry and cause further damage (this is known as "reperfusion injury").
Techniques for preventing damage to brain cells are an area of ongoing research. Hypothermia therapy for neonatal encephalopathy is the only evidence-supported therapy, but antioxidant drugs, control of blood glucose levels, and hemodilution (thinning of the blood) coupled with drug-induced hypertension are some treatment techniques currently under investigation. Hyperbaric oxygen therapy is being evaluated with the reduction in total and myocardial creatine phosphokinase levels showing a possible reduction in the overall systemic inflammatory process.
In severe cases it is extremely important to act quickly. Brain cells are very sensitive to reduced oxygen levels. Once deprived of oxygen they will begin to die off within five minutes.
Treatment is focused on reducing stroke episodes and damage from a distending artery. Four treatment modalities have been reported in the treatment of vertebral artery dissection. The two main treatments involve medication: anticoagulation (using heparin and warfarin) and antiplatelet drugs (usually aspirin). More rarely, thrombolysis (medication that dissolves blood clots) may be administered, and occasionally obstruction may be treated with angioplasty and stenting. No randomized controlled trials have been performed to compare the different treatment modalities. Surgery is only used in exceptional cases.
Pediatric FMD medical and surgical treatments or interventions are available. Treatment is determined by factors such as age and disease location but routinely involve controlling hypertension, re-establishing vascular flow, clot prevention, and improving lifestyle such as diet, exercise and smoking cessation.
Medical therapy for pediatric population may involve the use of angiotensin-converting enzyme inhibitor (ACE inhibitors) and/or angiotensin II receptor blockers, multiple anti-hypertensive medications, diuretics, calcium channel blockers, and beta-blockers. Prevention of thrombosis of affected arteries may be taken through administration of an antiplatelet medication such as aspirin.
Percutaneous transluminal renal angioplasty (PTRA) remains the gold standard for renal-artery FMD. This treatment is useful when hypertension is difficult to control; patient is intolerant to the anti-hypertensive medications, non-complainant to medication regime and patient loss of renal volume due to ischemia. PTRA can also aide in preventing a lifelong dependency on a medication for such a young patient. According to Meyers, “effective PTRAs result in cured or controlled blood pressure, which is often signified by reductions in plasma renin activity and angiotensin II levels, and when compared with surgery, percutaneous balloon angioplasty is less costly, able to be performed on an outpatient basis, results in lower morbidity, and the use of stenting is not primarily necessary.” However, there is a subset of the pediatric population that are resistant to PTRA. Adverse events may include, “recurrent stenosis, arterial occlusion with renal loss, and arterial rupture with extravasations and pseudo aneurysm formation and may require surgical intervention.
The prognosis for pediatric stroke survivors varies. The following are some common outcomes:
- Cerebral Palsy (often Hemiplegic Cerebral Palsy/Hemiplegia)
- Epilepsy
- Vision Loss
- Hearing Loss
Transfusion therapy lowers the risk for a new silent stroke in children who have both abnormal cerebral artery blood flow velocity, as detected by transcranial Doppler, and previous silent infarct, even when the initial MRI showed no abnormality. A finding of elevated TCD ultrasonographic velocity warrants MRI of the brain, as those with both abnormalities who are not provided transfusion therapy are at higher risk for developing a new silent infarct or stroke than are those whose initial MRI showed no abnormality.
There is currently no treatment or cure for CARASIL. Most frequently, a combination of supportive care and medications to prevent the occurrence of stroke are recommended.
There is no known cure for FMD. However, treatment focuses on relieving symptoms associated with it. Medical management is the most common form of treatment. The best approach to medically managing these patients is constantly being reevaluated as more information is learned about the disease.
Currently, there are no medications that have been approved specifically for prevention or treatment of vascular dementia. The use of medications for treatment of Alzheimer's dementia, such as cholinesterase inhibitors and memantine, has shown small improvement of cognition in vascular dementia. This is most likely due to the drugs' actions on co-existing AD-related pathology. Multiple studies found a small benefit in VaD treatment with: memantine, a non-competitive N-methyl-D-aspartate (NMDA) receptor antagonist; cholinesterase inhibitors galantamine, donepezil, rivastigmine; and ginkgo biloba extract.
The general management of dementia includes referral to community services, aid with judgment and decision-making regarding legal and ethical issues (e.g., driving, capacity, advance directives), and consideration of caregiver stress.
Behavioral and affective symptoms deserve special consideration in this patient group. These problems tend to be resistant to conventional psychopharmacological treatment and often lead to hospital admission and placement in permanent care.
Treatment for brain AVMs can be symptomatic, and patients should be followed by a neurologist for any seizures, headaches, or focal neurologic deficits. AVM-specific treatment may also involve endovascular embolization, neurosurgery or radiosurgery.
Embolization, that is, cutting off the blood supply to the AVM with coils, particles, acrylates, or polymers introduced by a radiographically guided catheter, may be used in addition to neurosurgery or radiosurgery, but is rarely successful in isolation except in smaller AVMs. Gamma knife may also be used.
From analysis of the existing small treatment trials of cervical artery dissection (carotid and vertebral) it appears that aspirin and anticoagulation (heparin followed by warfarin) are equally effective in reducing the risk of further stroke or death. Anticoagulation is regarded as more powerful than antiplatelet therapy, but anticoagulants may increase the size of the hematoma and worsen obstruction of the affected artery. Anticoagulation may be relatively unsafe if a large stroke has already occurred, as hemorrhagic transformation is relatively common, and if the dissection extends into V4 (carrying a risk of subarachnoid hemorrhage). Anticoagulation may be appropriate if there is rapid blood flow (through a severely narrowed vessel) on transcranial doppler despite the use of aspirin, if there is a completely occluded vessel, if there are recurrent stroke-like episodes, or if free-floating blood clot is visible on scans. Warfarin is typically continued for 3–6 months, as during this time the flow through the artery usually improves, and most strokes happen within the first 6 months after the development of the dissection. Some regard 3 months as sufficient.
Professional guidelines in the UK recommend that patients with VA dissection should be enrolled in a clinical trial comparing aspirin and anticoagulation if possible. American guidelines state that the benefit of anticoagulation is not currently established.
Treatment for lateral medullary syndrome involves focusing on relief of symptoms and active rehabilitation to help patients return to their daily activities. Speech Therapy is a very common form of rehabilitation that many patients undergo. Depressed mood and withdrawal from society can be seen in patients following the initial onslaught of symptoms.
In more severe cases, a feeding tube may need to be inserted through the mouth or a gastrostomy may be necessary if swallowing is impaired. In some cases, medication may be used to reduce or eliminate residual pain. Some studies have reported success in mitigating the chronic neuropathic pain associated with the syndrome with anti-epileptics such as gabapentin. Long term treatment generally involves the use of antiplatelets like aspirin or clopidogrel and statin regimen for the rest of their lives in order to minimize the risk of another stroke. Warfarin is used if atrial fibrillation is present. Other medications may be necessary in order to suppress high blood pressure and risk factors associated with strokes. A blood thinner may be prescribed to a patient in order to break up the infarction and reestablish blood flow and to try to prevent future infarctions.
One of the most unusual and difficult to treat symptoms that occur due to Wallenberg syndrome are interminable, violent hiccups. The hiccups can be so severe that patients often struggle to eat, sleep and carry on conversations. Depending on the severity of the blockage caused by the stroke, the hiccups can last for weeks. Unfortunately there are very few successful medications available to mediate the inconvenience of constant hiccups.
For dysphagia symptoms, Repetitive transcranial magnetic stimulation has been shown to assist in rehabilitation. Overall, traditional stroke assessment and outcomes are used to treat patients, since lateral medullary syndrome is often a cause of a stroke in the lateral medulla.
Treatment for this disorder can be disconcerting because some individuals will always have residual symptoms due to the severity of the blockage as well as the location of the infarction. Two patients may present with the same initial symptoms right after the stroke has occurred, but after several months one patient may fully recover while the other is still severely handicapped. This variation in outcome may be due to but not limited to the size of the infarction, the location of the infarction, and how much damage resulted from it.