Lp Stroke Non Hemoragik Pdf Download __LINK__
Hemorrhagic transformation (HT) is a common complication in patients with acute ischemic stroke. It occurs when peripheral blood extravasates across a disrupted blood brain barrier (BBB) into the brain following ischemic stroke. Preventing HT is important as it worsens stroke outcome and increases mortality. Factors associated with increased risk of HT include stroke severity, reperfusion therapy (thrombolysis and thrombectomy), hypertension, hyperglycemia, and age. Inflammation and the immune system are important contributors to BBB disruption and HT and are associated with many of the risk factors for HT. In this review, we present the relationship of inflammation and immune activation to HT in the context of reperfusion therapy, hypertension, hyperglycemia, and age. Differences in inflammatory pathways relating to HT are discussed. The role of inflammation to stratify the risk of HT and therapies targeting the immune system to reduce the risk of HT are presented.
lp stroke non hemoragik pdf download
Cerebrovascular accidents, commonly known as strokes, are prevalent across patient populations and can be a significant cause of morbidity and mortality. Strokes can be categorized as ischemic, hemorrhagic, or subarachnoid. This activity reviews the evaluation and management of ischemic cerebrovascular accidents and highlights the role of the interprofessional team in the recognition and management of this condition.
Stroke, a cerebrovascular accident, is prevalent across patient populations and can be a significant cause of morbidity and mortality. Strokes can be categorized as ischemic, hemorrhagic, or subarachnoid. Among ischemic strokes, the Trial Org 10172 in Acute Stroke Treatment (TOAST) classification is used to subdivide the categories that include cardioembolism, small-vessel occlusion, large-artery atherosclerosis, and stroke of undetermined etiology.[1]
The etiology of ischemic stroke is due to either a thrombotic or embolic event that causes a decrease in blood flow to the brain. In a thrombotic event, the blood flow to the brain is obstructed within the blood vessel due to dysfunction within the vessel itself, usually secondary to atherosclerotic disease, arterial dissection, fibromuscular dysplasia, or inflammatory condition. In an embolic event, debris from elsewhere in the body blocks blood flow through the affected vessel. The etiology of stroke affects both prognosis and outcomes.[2][3]
Stroke is the fifth most commonest cause of death if considered separately from other cardiovascular diseases. In the United States, an estimated 795,000 patients suffer from stroke annually, and the prevalence of stroke escalates with age. The lifetime risk of all types of stroke is higher in women; however, this is attributed to longer life expectancy.
Ischemic strokes can present in pre-determined syndromes due to the effect of decreased blood flow to particular areas of the brain that correlate to exam findings. This allows clinicians to be able to predict the area of the brain vasculature that can be affected.
The middle cerebral artery (MCA) is the most common artery involved in stroke. It supplies a large area of the lateral surface of the brain and part of the basal ganglia and the internal capsule via four segments (M1, M2, M3, and M4). The M1 (horizontal) segment supplies the basal ganglia, which is involved in motor control, motor learning, executive function, and emotions. The M2 (Sylvian) segment supplies the insula, superior temporal lobe, parietal lobe, and inferolateral frontal lobe.
Ischemic strokes present acutely, and establishing the time of symptom onset is critical. If the time of symptom onset is unknown, the time the patient was last known to be normal without new neurological symptoms is used. The time that is established is then utilized to decide whether giving intravenous thrombolytics is indicated or not.
A plain CT head or brain MRI is recommended for patients within 20 minutes of presentation to rule out hemorrhage. In hospitals that are stroke centers or can provide emergency care, vascular imaging should be considered for possible endovascular intervention; however, this should not delay the administration of thrombolytics.
Acute ischemic stroke can be seen on diffusion-weighted MR sequence. The FLAIR sequence helps in predicting the time since the onset of the stroke which is of paramount importance in planning thrombolytic therapy in the patient. The DWI features with no changes in the FLAIR sequence suggest the ischemic stroke is less than 6 hours old and therefore a candidate for early intravenous thrombolysis to revert the neurological deficit.
Other diagnostic tests include an electrocardiogram (ECG), troponin, complete blood count, electrolytes, blood urea nitrogen (BUN), creatinine (Cr), and coagulation factors. An ECG and troponin are suggested because stroke is often associated with coronary artery disease. A complete blood count can look for anemia or suggest infection. Electrolyte abnormalities should be corrected. BUN and Cr should be monitored as contrast studies may worsen kidney function. Coagulation factors, including PTT, PT, and INR, should also be done as the elevated levels can suggest a cause of hemorrhagic stroke.
For institutions without expert imaging interpretation, the US Food and Drug Administration highly recommends the teleradiology system for image interpretation for suspected stroke patients. This helps with the decision to administer IV alteplase. A discussion and agreement between telestroke neurologists and radiologists are highly recommended.
In areas that do not have an in-house stroke team or telestroke protocol, a telephone consultation may be considered for the administration of thrombolytics. The level of evidence is limited for this recommendation. [15][16][17]
The goal of therapy in acute ischemic stroke is to preserve tissue in areas where perfusion is decreased but sufficient to avoid infarction. Tissue in this area of oligemia is preserved by restoring blood flow to the compromised regions and improving collateral flow. Recanalization strategies include recombinant tissue-type plasminogen activator. Restoring blood flow can minimize the effects of ischemia only if performed quickly.
Endovascular techniques have been used in the treatment of acute ischemic stroke. Carotid endarterectomy has been but there is no evidence that supports its use in acute ischemic stroke. Another consideration is neuroprotective agents but none so far have been shown to improve clinical outcomes.
A review of the exclusion criteria for thrombolytics should be performed before administering alteplase. According to the Food and Drug Administration, the contraindications to intravenous thrombolysis include active internal bleeding, recent intracranial surgery or serious head trauma, intracranial conditions that may increase the risk of bleeding, bleeding diathesis, severe uncontrolled hypertension, current intracranial hemorrhage, subarachnoid hemorrhage, and a history of a recent stroke.
For patients that present between 3 and 4.5 hours from symptoms onset, the treatment benefits and risks must be considered. Additional relative exclusion criteria for this patient category include age more than 80 years, NIHSS greater than 25, oral anticoagulant use, and a history of both diabetes and prior ischemic stroke.
Other fibrinolytic agents, such as tenecteplase, may be considered as an alternative to alteplase. In one study, tenecteplase appeared to have similar efficacy and safety profiles in a mild stroke but did not demonstrate superiority when compared to alteplase [18][19].
In recent years there are significant advancements in acute stroke care. Multiple stroke trials in 2015 showed that endovascular thrombectomy in the first six hours is much better than standard medical care in patients with large vessel occlusion in the arteries of the proximal anterior circulation. These benefits are sustained irrespective of geographical location and patient characteristics.[20]
Again in 2018, a significant paradigm shift happened in stroke care. DAWN trial showed significant benefits of endovascular thrombectomy in patients with large vessel occlusion in the arteries of the proximal anterior circulation. This trial extended the stroke window up to 24 hours in selected patients using perfusion imaging. Subsequently, now more patients can be treated, even up to 24 hours.[21]
The current recommendation in selected patients with large vessel occlusion with acute ischemic stroke in the anterior circulation and who also meet other DAWN and DEFUSE 3 criteria, mechanical thrombectomy is recommended within the time frame of 6 to 16 hours of last known normal. In selected patients who meet the DAWN criteria, mechanical thrombectomy is reasonable within 24 hours of the last known normal [21][22].
The guidelines suggest blood pressure management of less than 180/105 mm Hg for the first 24 hours after IV alteplase. A new recommendation is lowering BP initially by 15% in patients with comorbid conditions such as acute heart failure or aortic dissection. There is no benefit of antihypertensive management to prevent death or dependency in patients with BP less than 220/120 mm Hg, who did not receive IV alteplase and have no comorbid conditions requiring blood pressure reduction. This applies to the first 48 to 72 hours after an acute ischemic stroke. For patients with greater than or equal to 220/120 mm Hg who did not receive IV alteplase, the guideline suggests it may be reasonable to reduce BP by 15% in the first 24 hours, although the benefit is uncertain.
Hyperthermia of greater than 38 C should be avoided and treated appropriately. Antipyretics such as acetaminophen may be used. Common sources of infection should be ruled out, such as pneumonia and urinary tract infections. There is insufficient data to support therapeutic hypothermia in acute ischemic strokes currently. A retrospective study recently demonstrated an association between a peak temperature in the first 24 hours of greater than 39 C (100.4 F) and an increased risk of in-hospital mortality.