According to the World Health Organisation, a Stroke is defined as an accident to the brain with "rapidly developing clinical signs of focal or global disturbance to cerebral function, with symptoms lasting 24 hours or longer, or leading to death, with no apparent cause other than of vascular origin and includes cerebral infarction, intracerebral hemorrhage, and subarachnoid hemorrhage". Show
Acute stroke is also commonly called a cerebrovascular accident which is not a term preferred by most stroke neurologists. Stroke is NOT an accident. The better and more meaningful term is "brain attack", similar in significance to "heart attack".[1] There are two main types of strokes[1].
Regardless o the type of stroke, it is important to know that with each minute of large vessel ischemic stroke untreated, close to two million neurons die. This is the most important "time is brain" concept in understanding acute stroke and its treatment. According to the World Health Organization (WHO), 15 million people suffer stroke worldwide each year. Of these, 5 million die and another 5 million are left permanently disabled.[2] The 2010 Global Burden of Disease Study suggested Stroke is the second leading cause of death globally and the third leading cause of premature death and disability as measured in Disability Adjusted Life Years (DALY). Cerebrovascular disease is the largest neurologic contributor and accounts for 4.1% of total global DALY. In the United States, there are 800,000 new strokes every year. There is one new stroke every 40 seconds. Stroke is the 5th leading cause of death and the first leading cause of disability. [1] Many etiologies can lead to a stroke. Some of the most common risk factors include [1]
At the base of the brain, the carotid and vertebrobasilar arteries form a circle of communicating arteries known as the Circle of Willis (see image below). From this circle, other arteries—the anterior cerebral artery (ACA), the middle cerebral artery (MCA) and posterior cerebral artery (PCA)—arise and travel to all parts of the brain. The image below clearly shows the function areas of the cerebral cortex that can be affected following insufficiency of the blood supply. Mechanism of Injury / Pathological Process[edit | edit source]A stroke occurs when there is an interruption of the blood supply to a particular area of the brain, ultimately leading to cell injury and cell death. Ischaemic strokes are the most common, accounting for up to 80% of strokes, and occur when there is an occlusion of a blood vessel impairing the flow of blood to the brain. Ischaemic Strokes are divided into:
According to the TOAST[5] classification, there are four main types of ischemic strokes.
Nb. Some experts do not classify Subarachnoid Haemorrhage as Stroke because subarachnoid haemorrhages present differently from Ischaemic Strokes and Intracerebral Haemorrhagic Strokes. 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. Cortical Areas and their vascular supply: Left MCA Superficial Division[edit | edit source]Right face and arm upper-motor weakness due to damage to motor cortex, nonfluent (Broca’s) aphasia due to damage to Broca’s area. There may also be right face and arm cortical type sensory loss if the infarct involves the sensory cortex. Other deficits include a fluent (Wernicke’s) aphasia due to damage to Wernicke’s area. [Aphasia: a disturbance of the comprehension and expression of language] Right MCA Superficial Division[edit | edit source]Left face and arm upper-motor weakness due to damage to motor cortex. Left hemineglect (variable) due to damage to non-dominant association areas. There may also be left face and arm cortical type sensory loss if the infarct involves the sensory cortex. Left MCA Lenticulostriate Branches[edit | edit source]Right pure upper-motor hemiparesis due to damage to the basal ganglia (globus pallidus and striatum) and the genu of the internal capsule on the left side. Larger infarcts extending to the cortex may produce cortical deficits such as aphasia. Right MCA Lenticulostriate Branches[edit | edit source]Left pure upper-motor hemiparesis due to damage to the basal ganglia (globus pallidus and striatum) and the genu of the internal capsule on the right side. Larger infarcts extending to the cortex may produce cortical deficits such as aphasia. Left PCA[edit | edit source]Right homonymous hemianopia due to damage to left visual cortex in the occipital lobe. Extension to the corpus collusom interferes with communication between the two visual association areas so it can cause alexia without agraphia. Larger infarcts involving the internal capsule and thalamus may cause right hemi-sensory loss and right hemiparesis due to the disruption of the ascending and descending information passing through these structures. [Hemoanopia: visual loss in half of the visual field] Right PCA[edit | edit source]Left homonymous hemianopia due to damage to the right visual cortex in the occipital lobe. Larger infarcts involving the internal capsule and thalamus may cause left hemi-sensory loss and left hemiparesis due to the disruption of the ascending and descending information passing through these structures. Left ACA[edit | edit source]Right leg upper-motor neuron weakness due to damage to the motor cortex and right leg cortical sensory loss due to damage to the sensory cortex. Grasp reflex, frontal lobe behavioral abnormalities, and transcortical aphasia can also be seen if the prefrontal cortex and supplemental motor areas are involved. Right ACA[edit | edit source]Left leg upper-motor neuron weakness due to damage to the motor cortex and left leg cortical type sensory loss due to damage to the sensory cortex. Grasp reflex, frontal lobe behavioural abnormalities and left hemineglect can also be seen if the prefrontal cortex and non-dominant association cortex are involved. NIH Stroke Scale Dynamic Gait Index, the 4-item Dynamic Gait Index, and the Functional Gait Assessment show sufficient validity, responsiveness, and reliability for the assessment of walking function in patients with stroke undergoing rehabilitation, but the Functional Gait Assessment is recommended for its psychometric properties[9]. Chedoke-McMaster Stroke Assessment Chedoke Arm and Hand Activity Inventory CRS-R Coma Recovery Scale Revised is used to assess patients with a disorder of consciousness, commonly coma. Take a look at our Stroke Outcome Measures Overview for more information The differential diagnosis is broad and can include stroke mimics such as TIA, metabolic derangement (in other words, hypoglycemia, hyponatremia), a hemiplegic migraine, infection, brain tumor, syncope, and conversion disorder.[1] Early Management of Acute Stroke[edit | edit source]The goal for the acute management of patients with stroke is to stabilize the patient and to complete initial evaluation and assessment, including imaging and laboratory studies, within a short time frame. Critical decisions focus on the need for intubation, blood pressure control, and determination of risk/benefit for thrombolytic intervention.[10] Patients presenting with Glasgow Coma Scale scores of 8 or less or rapidly decreasing Glasgow Coma Scale scores, require emergent airway control via intubation. A recent study has shown gait improvement with high-intensity interval training and moderate-intensity continuous training in ambulatory chronic stroke patients. According to post-stroke guidelines, moderate-intensity, continuous aerobic training (MCT) improves aerobic capacity and mobility after stroke. High-intensity interval training (HIT) has been shown to be more effective than MCT among healthy adults and people with heart disease. Physiotherapists should be involved early and should make their own assessment of how much they can work with a patient. Early mobilisation is associated with better outcomes - even after taking account of the potential confounding influence of disease severity. If rehabilitation is to take place on a different ward from acute care, the care received should be made as seamless as possible. The type and intensity of therapy should be determined by the patient's needs, not location.[11] Review by Harutoshi Sakakima et al. suggests that physical exercise acts as prototypical preconditioning stimuli that offer brain protection effects and are safe and workable treatment options for providing endogenous neuroprotection in patients with acute and chronic stroke[12]. A study by Carina U Persson et al. found that age, arm paresis, aphasia, and facial palsy at index stroke were predictors of increased muscle tone seven years post-ischaemic stroke[13]. A randomized study examining the effects of balance training with electromyogram-triggered functional electrical stimulation (EMG-triggered FES) to improve static balance, dynamic balance, and ankle muscle activation suggest positive results with stroke patients[14]. A single-blinded randomized controlled trial comparing the effectiveness of self-initiated sit-to-stand training with an assistive device with manual sit-to-stand training in a rehabilitation hospital of Hong Kong suggests positive outcomes with self-initiated sit-to-stand training on speeding up regaining the independence of sit-to-stand on sub-acute stroke survivors[15]. A Systematic Review suggests that only lifestyle interventions that include specific strategies targeting physical activity have a positive outcome on physical activity levels as compared to general lifestyle interventions[16]. Primary Goals of Rehabilitation[edit | edit source]
Optimising Post Stroke Rehabilitation[edit | edit source]
A randomized controlled trial suggests the CARE4STROKE program had a positive outcome on anxiety and depression of the patients[17]. Upper Limb[edit | edit source]Upper Limb Impairments:
In the upper extremity with severe impairment and/or poor prognosis for recovery (Chedoke McMaster Stroke Assessment (CMSA) of Arm and Hand < Stage 4) treatment should focus on maintaining a comfortable, pain-free, mobile arm and hand[18][19].
In the upper extremity with moderate impairments who show high motivation and potential for functional motor gains (CMSA => stage 4)[18][19]
Treatment Techniques:
Overall Management: National clinical guideline for stroke, The Royal College of Physicians, September 2012 What is the common term for cerebrovascular accident?A stroke, also referred to as a cerebral vascular accident (CVA) or a brain attack, is an interruption in the flow of blood to cells in the brain.
What is the most common form of cerebrovascular disease?The most common one is stroke. Other conditions include brain aneurysms, brain bleeds, carotid artery disease and transient ischemic attacks (TIA) or mini strokes, among others.
What is the most common cause of a cerebrovascular accident?There are two main causes of stroke: a blocked artery (ischemic stroke) or leaking or bursting of a blood vessel (hemorrhagic stroke). Some people may have only a temporary disruption of blood flow to the brain, known as a transient ischemic attack (TIA), that doesn't cause lasting symptoms.
|
