What is a Stroke?


The terms ‘stroke’ or ‘cerebrovascular accident’ are used to describe neurological signs and symptoms that result from diseases of blood vessels. A stroke has rapid onset with neurological symptoms persisting for more than 24 hours and may present as a sudden and unexplained lack of consciousness. Even though strokes usually occur without warning there is generally a significant amount of pre-existing cerebrovascular disease that has occurred over a long period. This pre-existing condition may have already damaged some cognitive functions in the individual. Strokes differ in severity with individuals suffering moderate or severe strokes often enduring some degree of motor, sensory, cognitive, or speech impairments as a result of the brain damage. The extent and type of impairment stroke-survivors face as well as options for treatment depend on the amount and location of damage. However, the most common deficits for stroke survivors involve motor action.

Types of Stroke and aetiology

Stroke can be broadly divided into those ersulting from infarction of the brain (ischaemic stroke) and those resulting from intracerebral and subarachnoid haemorrahage (haemorrhagic stroke). Approximately 85 per cent of strokes result from infarction, with the remaining 15 per cent being due to haemorrhage. There are many causes of the infarction of haemorrhage, and these are summarised in Panel 1. Where one of hte major arteries to the brain is occluded, such as the midle cerebral artery, this is most frequently due to embolism of either a blood clot from the heart, or of atheromatous material and a blood clot from the carotid artery. Occlusion of the smaller perforating arteries resulting lacunar strokes is most frequently due to local arterial disease resulting from hypertension or diabetes.

Ischaemic Stroke

Ischaemic stroke or Transient ischaemic attack (TIA) is defined as a transient episode of neurological dysfunction caused by focal brain, spinal cord, or retinal ischaemia with acute infarction. These patients are at high risk for early ischaemic stroke. Since brain imaging sometimes shows evidence of infarction even in those with transient symptoms, a re-definition of TIA has been proposed, based on transient symptoms and lack of evidence of infarction on imaging.

Haemorrhagic Subarachnoid Stroke

Haemorrhagic stroke is due to rupture of a cerebrospinal artery, resulting in intraparenchymal and/or subarachnoid haemorrhage. Intracerebral haemorrhage is further subdivided into primary and secondary aetiology. Primary or spontaneous intracerebral haemorrhage is defined as haemorrhage in the absence of vascular malformations or associated diseases. Secondary intracerebral haemorrhage is from an identifiable vascular malformation or as a complication of other medical or neurological diseases that either impair coagulation or promote vascular rupture.

Research demonstration

Research demonstrates the non-adaptive quality of depression in stroke patients not only through its strong links to quality of life (Fruhwald, Loffler, Eher, Saletu, & Baumhackl, 2001), but also through its impairment in physical activities and language (Parikh et al., 1990) and mortality (Dean, 2004; Everson, Roberts, Goldberg, & Kaplan, 1998; Williams, Ghose, & Swindle, 2004). Links to mortality remain after the variables of social ties, mental status, alcohol use, medical co-morbidity, marital status, age, sex, social class, type of stroke, lesion location, and levels of functioning including social functioning are controlled for (Morris, Robinson, Andrzejewski, Samuals, & Price, 1993).

Much research has investigated possible factors leading to depression in stroke patients. For example, the Burvill (1997) study suggests that post-stroke depression may have the same risk factors as associated with depression in other contexts such as major functional impairments and living in a nursing home. However, this study only examined physical and social predictors of depression in stroke patients. Although much research illustrates that physical factors can predict post-stroke depression, the extent to which psychological variables predict depression in stroke patients needs further investigation. Self-regulation theory provides a theoretical basis for understanding the interplay of these psychological processes with physical and social dynamics to influence emotional and behavioural responses to illness conditions such as stroke.

Diagnosis of Stroke

The goals of the initial evaluation are to identify the stroke syndrome, ensure medical stability, perform an abbreviated neurological examination, and rapidly transport the patient to the CT or MRI scanner to begin scanning within 25 minutes of arrival in the emergency department. Because of time constraints, certain portions of the history and physical examination may be deferred until after scanning and the decision to perform thrombolysis. This is because the sensitivity and specificity to correctly diagnose and localise ischaemic stroke from the neurological history and examination are fairly low. Additionally, many other neurological conditions can mimic stroke. The proper diagnosis of stroke requires craniocervical CT and/or MRI.

Ischaemic stroke
Prior medical information relevant to the acute management of Ischaemic stroke includes:
  • Recent stroke
  • Seizure or epilepsy
  • MI
  • Atrial fibrillation
  • Surgery
  • Trauma
  • Bleeding
  • History of haemorrhagic stroke
  • Co-morbidities (specifically HTN and diabetes)
  • Current or past illicit drug use
  • Medicines (specifically anticoagulants, insulin, and antihypertensives).

Haemorrhagic stroke
The medical history may identify diseases associated with impaired coagulation, including liver disease and haematological disorders. A complete medication history is important for identifying those patients with anticoagulant-associated haemorrhage. In most cases, the symptoms of intracerebral haemorrhage evolve over seconds or minutes. The most common symptoms are:
  • Limb weakness
  • Paraesthesias or numbness
  • Dizziness
  • Vertigo
  • Nausea/vomiting
  • Speech difficulty
  • Visual loss or double vision
  • Confusion
  • Sudden Headache/ Migraine
  • Loss of balance and coordination

Treatment and Recovery

Nearly two-thirds of people experiencing a first time stroke survive one year after it, however about one in five die within the first 28 days.
First time stroke victims become more prone to a recurrent stroke with approximately one in six of them who survive the first two days, likely having a recurrent stroke over the next five years. Most stroke survivors would often become dependent on others for daily activities even after a rapid recovery during the early weeks following the stroke.

After patients have met the criteria, they often given medication such as t-PA (tissue plasminogen activator)- the only FDA-approved drug for strokes, they can begin this treatment which significantly reduces long-term disability, given that the patient receives it within the first three hours after an ischemic stroke.
Hemorrhagic strokes on the other hand, proven to be more fatal, will require a neurosurgical evaluation with a portion of victims having to undergo surgery.
Other available drugs are Citicoline, a more generic drug which is only available in some countries, prove to demonstrate some controversial results based on some recent ongoing clinical trials. There are also drug treatments such as Cerebrolysin containing biological neuropeptides which actively help in treating hyperacute ischemic strokes, along with another treatment originating from traditional chinese medicine. This form of medication is widely know as Neuroaid, which has proven to be effective in both ischemic and hemorrhagic strokes.

An important part of treatment to decrease the negative after-effects of stroke would be a medical care plan which can be found in specialised stroke centres to help rehabilitate the patients and to help them cope with their subsequent physical as well as emotional difficulties.

Patients recovering from a stroke require time to adapt to the certain changes they are going through. Stroke survivors have a high chance of developing post-stroke depression, affecting their eating, sleeping habits and their moods. They may experience pain, numbness, odd sensations or a one sided neglect towards the affected side of the body, manipulating their general perception of the world.
It is crucial to seek guidance from professional help as well as family, to improve and rebuild their quality of life.

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