Cerebrovascular accident.pptxbbbbfraathjhy6

Useful Investigations for Evaluating the Respiratory System.ppt

1. Cerebrovascular accident DR NDIONUKA IJEOMA MBBS, FWACP

2. Outline Introduction classification aetiology clinical presentation

3. Introduction Stroke(cerebroascular accident) “brain attack” is classically characterized as a neurological deficit attributed to an acute focal injury of the central nervous system (CNS) by a vascular cause, including cerebral infarction, intracerebral hemorrhage (ICH), and subarachnoid hemorrhage (SAH). It is a major cause of disability and death worldwide.

4. Stroke remains the second leading cause of death and the third leading cause of death and disability combined in the world. From 1990 to 2019, the burden of stroke (in terms of the absolute number of cases) increased substantially with the bulk of the global stroke burden (86.0% of deaths) residing in lower-income and lower-middle-income countries (LMIC).

5. WHO Facts Globally, there are over 12.2 million new strokes each year. Approximately one in four people over age 25 will experience a stroke in their lifetime. 16% of all strokes occur in individuals aged 15-49 years. 62% of all strokes happen in people under 70 years of age. 47% of strokes affect men, while 53% occur in women. Currently, there are over 101 million people living who have experienced a stroke.

6. Definition The term “stroke” should be broadly used to include all of the following: CNS infarction: CNS infarction is brain, spinal cord, or retinal cell death attributable to ischemia, based on 1. pathological, imaging, or other objective evidence of cerebral, spinal cord, or retinal focal ischemic injury in a defined vascular distribution; or 2. clinical evidence of cerebral, spinal cord, or retinal focal ischemic injury based on symptoms persisting ≥24 hours or until death, and other etiologies excluded.

7. In its simplest form, stroke is an acute episode of focal neurological dysfunction that persists for more than 24 hours.

8. Classification of stroke Stroke is categorized into mainly 2 types: Ischemic stroke Hemorrhagic stroke.

9. Subtypes of Ischaemic stroke The Trial of Org 10172 in Acute Stroke Treatment (TOAST) classification system identifies 3 primary causes of ischemic stroke: large vessel disease. small vessel disease (lacunar). cardioembolism.

10. Large vessel disease encompasses conditions such as atherosclerosis, arterial dissection, and artery-to-artery embolism. Large vessels comprise intracranial arteries (including the circle of Willis and its proximal branches) and extracranial arteries (including common carotid, internal carotid, and vertebral arteries)

11. Lacunar strokes, predominantly caused by small vessel diseases, are commonly associated with lipohyalinosis and atherosclerosis. Lipohyalinosis refers to the concentric hyaline thickening of small cerebral vessels leading to the occlusion of penetrating arteries.

12. Cardioembolism, as a cause of stroke, can stem from various sources, including arrhythmia, valvular heart disease, bioprosthetic and mechanical heart valves, and cardiomyopathy.

13. mechanism of stroke Thrombotic Embolic

14. Bamford’s classification This classification, also known as Oxfordshire or Bamford’s classification, relies exclusively on clinical findings. It classifies strokes according to the brain territory involved.

15. Anterior circulation stroke, the areas supplied by the Middle cerebral artery and Anterior cerebral artery. Posterior Circulation Stroke, the areas supplied by the posterior cerebral artery and basilar artery.

16. Haemorrhagic stroke 1. Intracerebral haemorrhage 2. Subarachnoid haemorrhage

17. Haemorrhagic stroke ICH stands as the second most prevalent form of stroke. ICH is typically caused by the rupture of small arteries, often due to hypertensive vasculopathy, cerebral amyloid angiopathy (CAA), coagulopathies, and other vasculopathies.

18. SAH Approximately 5% of all strokes are caused by spontaneous SAH due to a ruptured aneurysm in 85% of patients. Other causes of spontaneous SAH include drug use (such as amphetamines and cocaine), coagulopathy, a ruptured arteriovenous malformation, and vessel rupture due to a dural venous sinus thrombosis.

19. Pathophysiology The pathophysiology of ischemic stroke begins with insufficient blood supply to a focal area of brain tissue. Within minutes, the central core of tissue in this affected area progresses toward irreversible damage, known as the area of infarction. However, the surrounding tissue, referred to as the penumbra, does not experience immediate cell death and has the potential for recovery if early reperfusion is achieved.

20. In regions of reduced blood flow, there is an imbalance between the consumption and production of adenosine triphosphate (ATP), resulting in diminished energy stores. This leads to ionic imbalances, electrical disturbances, and a cascade of ischemia-related changes.

21. These changes increase the production of reactive oxygen species (ROS) and nitric oxide (NO). Over time, the pathophysiological cascade destroys cell membranes, cell lysis, and cell death through mechanisms such as necrosis or apoptosis.[

22. Risk factors for stroke Modifiable Hypertension Diabetes mellitus Atrial fibrillation Dyslipidemia Smoking tobacco

23. Sedentary lifestyle Kidney disease Sleep apnea Heavy alcohol intake Diet

24. Nonmodifiable Male sex Genetic susceptibility Age

25. Presentatio n Frontal lobe memory personality disorders hemiparesis behavioural problems

26. Parietal lobe hemisensory loss hemi neglect hemiparesis

27. Temporal lobe dysphasia hemiparesis seizures hemiaopsia

28. Occipital lobe cortical blindness double vision headaches hemiparesis

29. cerebellum ataxia vertigo vomiting difficulty swallowing

30. Thank you for listening

31. References WHO fact sheet AHA/ASA Journals