Stroke: Symptoms, Prevention And Treatment
The range and seriousness of early stroke symptoms vary, yet they all tend to occur suddenly. When stroke leads to damage or death of brain tissue effects can be seen in those parts of the body that damaged brain cells control. As one side of the brain has control over the contrary side of the body, a stroke that caused issue in blood perfusion of right side of the brain will present in symptoms on the left half of the body (Heros, 1994). For example, symptoms of stroke that affected blood supply to the right side of the brain can be vision and memory issues, snappy, curious or purposeless behaviour. While symptoms of stroke on the left side may be loss of motion on the right side of the body, language issues and very cautions behaviour (Freberg, 2009). For instance, partial blockage of middle cerebral artery leads to inadequate delivery of oxygenated blood required for normal metabolism of brain cells in different areas of the brain. As a result, patients can present with symptoms such as facial weakness, partial aphasia and hand weakness. While in complete occlusion of the middle cerebral artery patients can present with symptoms such as loss of movement and sensation on the opposite side of the body or even the same side as brain infraction. If injury happens in categorical hemisphere, patients often present with global aphasia (Frizzell, 2005). If cells are damaged in the representational hemisphere issues such as neglect syndrome can occur. Another examples of stroke presentation are 2 syndromes observed with occlusion of the posterior cerebral artery, known as P1 and P2 syndrome. The P1 syndrome presents when there is damage to the cells of the midbrain, subthalamic, and thalamic areas. This is presented through third-nerve paralysis with ataxia and weakness. Moreover, if damage has been extensive additional symptoms such as unreactive pupils and even coma can develop. The P2 syndrome presents when cells of medial temporal and occipital lobes are damaged. The result of damage are memory and visual issues on the contralateral side of the stroke. Sometimes visual issues can produce hallucinations. Symptoms such as cerebellar ataxia, nausea, vomiting, hearing problems and loss of pain or temperature sensation can occur when there is interruption to blood flow of superior cerebellar artery (Frizzell, 2005). While symptoms such as ipsilateral deafness and vertigo can be seen with occlusion of inferior cerebellar artery. Moreover, damage to anterior left hemisphere can often lead to increased depression in post stroke patients (Aström, et al. 1993).
Fast and precise analysis of the type of stroke and the specific area of its damage is necessary for positive treatment outcome. Treatment objectives when managing stroke incorporate stabilization of the patient and improvement of cerebral perfusion in order to avoid further brain damage. The initial treatment should incorporate supportive medications too. For example, beta 1 adrenergic antagonists can be used to maintain healthy blood pressure levels by decreasing heart workload (O’Fallon, et al. 2004; Heros, 1994). Fever and high blood sugar levels are shown to be harmful for recovery, their regulation is of high importance. Loss of consciousness is often symptom of stroke as delivery of oxygenated blood to brain cells is interrupted. Therefore, important treatment objective is to maintain airways clear in the event of consciousness issues. Once patient is stable and there is no risk for the life, diagnostic measures are used to determine the stroke etiology. Results of this investigations will determine further steps in treatment protocol.
Treatment of an ischemic event will incorporate use of anticoagulants, anti-platelets, thrombolytic and neuroprotective medications. However, systemic review of 20 000 of cases, comparing use of anticoagulant medications with control showed that use of anticoagulants immediately following the stroke helps to prevent complications such as deep vein thrombosis, but it had no effect on recovery of the patient (Gubitz, & Sandercock, 2000). First choice thrombolytic medication for treatment of an ischemic stroke is tissue plasminogen activator. The main drawback of this medication is that it must be administered within three hours from the onset of symptoms. Current data shows that only 3 to 5 percent of patients suffering from stoke arrives to emergency department in this time period. This medication has a risk for increased intracranial haemorrhage and therefore is not used for treatment of haemorrhagic stroke (O’Fallon, et al. 2004). The use of neuroprotective agents is widely debated, however there is an ongoing research to develop neuroprotective agents that would aim to block amino acid pathways with the final goal of decreasing neurotransmitter activity of injured tissue (Kasper et al., 2015).
Surgical treatments for ischemic stroke include microcatheter-based surgeries and use of cloth retrieval devices (Kasper et al., 2015; O’Fallon et al., 2004). When micro-catheters are used, the main goal is to reach the part of the brain where the blockage occurred. Thrombolytic medication is then administered directly to thrombus. This type of treatment has benefits such as being more specific, requiring lower dose of medication and having longer time for administration then when the same medication is used intravenously. When clot retrieval devices are used a small catheter is guided to the arteries in the neck. Once it reaches neck, a smaller catheter is implemented further in the brain arteries until it reaches the blockage. In the most devices small wire is then used to remove the cloth and a balloon inflated in the neck artery is used to cut off the blood flow. Once this is established the clot can be removed safely.
When cerebral haemorrhages occur, specific treatments designed to reduce intracranial pressure are used. This include osmotic agents such as mannitol or glycerol, steroids or hyperventilation. However, there is no convincing evidence that these treatments help to improve stroke outcome (Kasper et al., 2015). Therefore, surgery to relieve intracranial pressure caused by bleeding is often the first treatment choice. Surgery may be performed to remove the portion of the skull and relieve increased intracranial pressure. This procedure is known as a craniectomy. In addition to craniectomy if the cause of haemorrhage is an aneurism, the clips can be applied to the base of aneurysm. These clips are permanent and most often provide satisfactory results. At the end of the procedure it is important to run necessary diagnostic tests to confirm that aneurysm has been adequately treated. However, most of the time elimination of the aneurysm is only the beginning. Intensive care recovery is necessary to prevent complications such as brain swelling, delayed cerebral vasospasm, intercurrent infections and hydrocephalus (Kasper et al., 2015; O’Fallon et al., 2004). While surgical intervention is indicated in comatose patients or those patients whose consciousness level is rapidly deteriorating, less invasive procedures are preferred. For example, utilization of endovascular microcil embolization has advantage of no incision to the skull and shorter time under the anaesthesia. During this procedure a small catheter is inserted through the femoral artery. With x-ray guidance, the catheter is feed to the brain. A smaller microcatheter is then inserted into the aneurysm and a thin wire filament, designed to adapt to the shape of the aneurysm is placed. Additional coils are advanced into the aneurysm to close the aneurysm from the inside. This prevents flow of blood into the aneurysm by causing a clot to form on the inside. Endovascular technology is in a constant state of development (Asadi, 2015).
Stroke prevention includes many different factors, such as lifestyle changes and medications. It is critical to asses each patient individual risk factors and focus on improving that areas. Smoking cessation is another important factor for stroke prevention. As smoking is known to lead to reduced oxygen delivery to brain tissue and atherosclerosis it directly effects metabolism of brain tissue. Moreover, current research argues that risk for stroke increases with number of smoked cigarettes per day (Adams, 2003). Both eating regimen and exercise can be utilized to help control circulatory strain and cholesterol levels. Sometimes dieting and healthy lifestyle lone cannot provide adequate prevention, therefore medication treatment is required (Freberg, 2009).
Medications commonly used to prevent the stroke are anticoagulants and antiplatelet agents. Anticoagulants, such as Warfarin thin the blood and prevent clotting. Antiplatelet drugs make platelets less sticky and less likely to form clots that may lead to the ischaemic stroke (Kutner et al., 1991). Additional medications might be required for the control of blood pressure and cholesterol levels. Satisfactory control of blood pressure helps reduce risk of stroke in older adults. One of the known medications are ACE inhibitors (Di Napoli, & Papa, 2003).
Surgical procedures such as carotid endarterectomy surgery, carotid angioplasty and stenting are used to prevent the stroke (Sardar et al., 2017; Barnett et al., 1999). During carotid endarterectomy an incision is made in in the carotid artery and dissecting tool is used to remove the plaque build-up. In the end this helps to restore normal blood flow to the brain. Carotid angioplasty and stenting are often used in patients that may be at high risk to undergo surgery. During carotid angioplasty the doctor guides a balloon-tipped catheter into the blocked artery. Plaque is pressed by the balloon which allows reopening of blocked artery. Carotid stenting is neurointerventional procedure in which a small metal-mesh tube is guided through small groin incision and fitted inside the carotid artery to increase the blood flow. Usually the stent is placed following the angioplasty to prevent the artery from collapsing after the procedure (Sardar et al., 2017).
Prognosis for the full recovery following the stroke is highly dependent on the extent and area of damage to the brain cells. Other important factors that have an effect on recovery are patient’s age, well-being before the event and physical therapy following the event (Gubitz, & Sandercock, 2000).
The fatality rates following the first experienced stoke for all types combined are 12% at 7 days, and as high as 31% at 1 year (Dennis, et al. 1993). Recovery of the patients who experience a cerebral haemorrhage mainly depends on haemorrhage volume. Therefore, the haemorrhage volume greater than 60 ml have poor prognosis (Kasper, et al. 2015).
While brain damage is the leading cause of deaths that occur within the first week following the stroke, later the immobility complications and cardiac events become progressively common cause of death (Frizzell, 2005). Statistics show that about 20% of stroke patients become highly dependent on another person for 12 months (Aström, et al. 1993).
The risk of recurrent stroke is between 10 and 16 percent within the first year following the initial stroke. Following this period risk falls even further (Burn, et al. 1994).