Stroke Lecture 1 Flashcards
What is Stroke?
Rapid loss of brain function due to disturbances in the blood supply
What are the causes of stroke ?
Ischemia and Hemorrhage
What is an Ischemia?
lack of blood supply to the brain
What is a Hemorrhage?
Burst of a blood vessel
What happens to where the stroke occurs?
The affected area of the brain cannot work properly
What are the effects of a Stroke (6)?
Movement (Paralysis to one side
Speech and Language
Eating and Swallowing
Vision
Cognition
Perception
What is Hemiparesis
Paralysis to one side of the body
What is the prevalence of Stroke (Epidemiology)
Second Leading cause of mortality
50% end up with permanent disability
1/5 will have a stroke in their lifetime
What is the energy consumption of the brain?
largest source of energy in body
20% of oxygen
50% of glucose
What is vascular dementia?
Mismatch between cerbral blood flow and metabolic demand
Why is the brain vulnerable to Ischemia
High energy requirements compared to low energy reserves, makes the brain vulnerable to lack of blood supply
What does “Time is Brain” mean ?
Blood flow should be restored asap, to prevent rapid irreversible damage
What is an Ischemic Core?
Ireversibly damaged area.
Blood and oxygen flow are severely diminished resulting in neuronal death
What is the Penumbra
Reversible injured brain tissue, surrounding irreversible ischemic core
How long are Ischemic penumbra cells viable for
6h-3 days
What is the subacute phase of stroke
6-11 days. if cells are untreated during this time the penumbra succumbs to cell death
What is Necrosis
Cell death
What is infarctation
Tissue death due to lack of blood supply
Complication of Stroke
Edema
What is Edema
Brain swelling that can develop 24-48 h after stroke—– reaches peak 2-5 days after onset stroke
What is ICP
Increased Intracranial Pressure- rise of pressure inside the skull (brain tissue cannot expand)
What is an Ischemic Stroke
A blood clot or other blockages causing a decrease in blood flow to brain
What causes an Ischemic Stroke ?
Thrombosis and Embolism
What are the symptoms of an ischemic stroke
Sudden numbness or weakness of face, arm or leg
Sudden confusion, trouble speaking, vision problems
Sudden trouble walking
What is the therapy for an Ischemic Stroke
Thrombolysis(dissolving of blood clot)
Mechanical Thrombectomy
Aspirin
Anticoagulants (warfarin)
Statins
Antipyretics
Neuronprotection (anti-inflammatory)
What is a Hemorrhagic Stroke
Weakened vessel ruptures and bleeds into the surrounding brain
What are the causes of Hemorrhagic Stroke
High blood pressure
Ruptured aneurysm
Head injuries
Bleeding disorders
What are the symptoms of a Hemorrhagic Stroke
Similar to Ischemic–
Causes severe sudden headache and stiff neck due to subarachnoid bleeding
What is the therapy for Hemorrhagic Stroke ?
Surgical Clipping/Coil embolization
Medicines to reduce intracranial pressure (osmotic diuretics)
bp management
What is the likelyhood of a stroke reoccuring
30% of strokes are reoccurent
What are anticoagulants
slow down blood clotting
What are anitplatelets
to prevent blood clotting
What two pairs of vessels supply the brain with blood
Internal Carotid arteries
Vertebral Arteries
Where do the internal carotid and vertabral arteries connect
in the cranial cavity to create the CIRCLE OF WILLIS
What does the internal carotid arteries supply
anterior blood supply of the brain
What do the vertebral arteries supply
posterior blood supply of the brain
What is the anatomy of the interal carotids
Begins at the Carotid Bifurcation on either side of the neck
Each artery travels up through the neck to base of skull
Goes through opening in skull known as CAROTID CANAL
Connects with the CIRCLE OF WILLIS
Terminate middle and anterior cerebral artery
The anterior cerebral arteries are connected by the anterior communicating artery
What makes up anterior circulation
The interal carotids and their branches
What are the branches of the internal carotid
anterior cerebral arteries
middle cerebral arteries
What happens when there is an anterior circulation stroke
Unilateral weakness
Dysphasia
Visual Field Defects
What is the anatomy of the vertebral arteries
Originate in subclavian area
enter skull through foranum magnum
Two vertebral arteries join to form basilar artery and connect to the CIRCLE OF WILLIS
Terminates by ifurcating into posterior cerebral arteries
What is the anatomy of the external carotids
Begin at the carotid bifurcation on neck
Travel along neck up to ears
Near ear, it divides into its two terminal branches: maxillary artery and superficial temporary artery
What is the function of the external carotid
Blood supply to face and neck area
What are meninges
Connective Tissue membranes which ensheath the brain and spinal cord
What is the function of the meninges
protect brain and achor in bone cavity
What are the three layers
Dura mater
Arachnoid Mater
Pia Mater
epidural/extradural Space
potential space between dura mater and bone
Subdural space
potential space between arachnoid and dura mater
Subarachnoid Space
potential space between arachnoid mater and pia mater
What are the types of intracranial bleeding
Intra axial
extra-axial
Intra- axial bleeding
bleeding in the brain
Extra-axial bleeding
outside the brain but within the skull
What are the three types of extra-axial haemorrhages
Epidural Haemorrhage
Subdural Haematoma
Subarachnoid
Epidural Haemorrhage
bleeding between dura mater and the skull
Subdural Haematoma
bleeding in the subdural space
Subarachnoid Haemorrhage
Bleeding between the arachnoid and pia mater
