Neuro patho Flashcards
What is the patho for Parkinsons?
Basal ganglia compromised
Degeneration of nigrostriatal pathway
Leads to reduction of neurotransmitter dopamine
Imbalance of excitatory and inhibitory neural motor pathways
Neurons change pigment colour and atrophy
Impairment to extrapyramidal tracts controlling complex body movement
What is the patho for a TBI?
Brian suffers traumatic brain injury
brain swelling or bleeding increase intracranial pressure
rigid cranium allows for no room for expansion of contents so intracranial pressure increases
pressure on vessels in the brain causes blood flow to slow in the brain
cerebral hypoxia and ischaemia occurs
intracranial pressure continues to increase. brain may herniate
cerebral blood flow ceases
What is the patho if Autonomic Dysreflexia?
strong pain sends signals to spinal cord via intact peripheral nerves
CNS sense this input as it travels up spinal cord evoking a massive peripheral sympathetic response through spinal reflexes and sends the SNS signals and vessels vasoconstrict below T6
vessels continue to constrict as they try send signals to the brain
brain detects hypertensive crisis through baroreceptors in carotid and aortic arch but signals cannot relax or decrease pressure
brain attempts two maneuverers to
halt hypertensive crisis
brain attempts to shut down
sympathetic surge by sending
descending inhibitory impulses,
impulses are unable to travel to most
sympathetic overflow areas due to
spinal cord being severed and
attempts to decrease peripheral blood
pressure through an intact vagus
nerve, compensatory bradycardia is
inadequate and hypotension
continues
What is the patho of a Stroke?
blood flow is disrupted to a portion of the brain
ischaemic cascade of events and biochemical. reactions initiated within the brain
inflammation
death of neurons
loss of perfusion to part of the brain
ischaemic neurons depolarised
ATP is depleted and membrane ions transport system fails
neurotransmitters are released through influx of calcium
excitatory receptors on other neurons activated
neurons depolarised
further influx of calcium/further
neuronal excitation
neuronal damage is exacerbated by
excessive calcium influx
released destructive enzymes –
release of free radical – presence of
potent chemical mediators
ischaemic areas
functional loss
