Brain problems Flashcards
What is the reticular activating system?
Key role in consciousness for arousal and waking state, contributes to muscle tone, mood, attention, motivation, learning and memory.
What parts of the Brain are responsible for the reticular activating system?
the brain stem and the thalamus and part of the hypothalamus
What are the 7 levels of consciousness changes in waking state
- Fully conscious
- Confusion
- Delirium
- Lethargy( slow and tired)
- Obtundation
- Stupor
- Coma
Describe what “fully conscious” is
The states of being awake and alert: aware of ones environment and cable of responding appropriately
Describe what “confusion” is
The affected person is disoriented to time and place; they have difficulty following instructions
Describe what “Delirium” is
The affected person experiences disorientation and mental confusion as a result of hallucinations and delusions
Describe what “Lethargy” is
The affected person is drowsy, but can be aroused by moderate stimuli
Describe what “Obtundation” is
The affected person is more drowsy than in lethargy, with less interest in their environment and slowed response when roused
Describe what “Stupor” is
The affected person can be aroused only by vigorous stimulation, and immediately lapses into their previously unresponsive state
Describe what “Stupor” is
The affected person can be aroused only by vigorous stimulation, and immediately lapses into their previously unresponsive state
Describe what “Coma” is
The affected person is unresponsive and cannot be aroused from this state
What are some common intracranial ALOC causes?
Head injury,
hemorrhage,
Degenerative conditions,
Space-occupying lesions (SOL),
Increased intracranial pressure,
Vasospasm of cerebral vasculature
What are some common Extracranial ALOC causes?
Hypoxia, HTN, profound hypotension, systemic infection, hepatic or renal dysfunction, hypo- or hyperglycemia, electrolyte imbalances, pH balance, medications and other chemicals
What things is the Glasgow coma scale checking
Measuring the responses of eyes opening, verbal commands, and motor movement
What is a Cerebrovascular accidents (CVA)
( stroke) caused by blood vessels being blocked or bleeding (ischemic vs hemorrhagic)
-involves a Cerebral infarction
- Consequences of stroke depend on part of brain effected
What is a Cerebral infarction and what are the 2 types
blockage of O2 causing cells to die – neurons will die
*Primary infarction zone – neurons irreversibly injured (will no longer work)
*Secondary infarction zone – immediately around the primary zone – cells injured but can recover if blood flow is restored quick enough
What is a Transient ischemic attack (TIA)
stroke like symptoms that occur due to hypoxic event, but have recovered and are okay (usually in 24hrs)
-Usually an indicator of underlying thrombotic disease
-Warning sign that high risk of CVA
-Antithrombotic drugs can decrease chance of having a CVA
-Still needs and investigation
What are risk factors for CVA’s
- over the age of 65 (slower metab, hormones change, heart disease, aging of organs, lack of mobility)
-sex (high in males)
-HTN
-hyperlipidemia - increased alcohol intake
- Smoking
- Lack of exercise
heart diseases - Family Hx (Death rates high in ppl of European decent)
Leading cause of death in Australia and New Zealand 7-10% of all deaths
How are CVAs diagnosed
-CT, MRI, angiography, bloods (rule of other LOC)
-Physical assessment, obs, neuro obs, motor/ sensory assessment Hx
-Need to determine if ischemic or hemorrhagic
How are CVAs treated
Thrombolysis if ischemic cause
surgical clipping if hemorrhagic
What is the circle of Willis
Circle of blood vessels in in the brain… if there is a blockage, there is another blood vessel that can get to that area of the brain
what is an Aneurysm
Ballooning of the vessel making it have weak areas of walls. Can burst and bleed out.
Language happens in what area of the brain
Broca’s area, Wernicke’s area
Speech happens in what area of the brain
Broca’s area
Voluntary movement (or muscle weakness) happens in what area of the brain
Frontal lobe, brain stem
Vision happens in what area of the brain
Occipital lobe, brain steam
Confusion (or disorientation) happens in what area of the brain
Frontal lobe
Balance (or disequilibrium) happens in what area of the brain
Brain stem, cerebellum
eye movments happens in what area of the brain
Brain stem
Altered coordination and gait happens in what area of the brain
Cerebellum
What is meningitis and what are the 2 classifications
inflammatory process of the membranes that surround the brain and spinal cord.
Two classifications:
Bacterial (common) - enter the CNS by violating the blood-brain barrier after an upper airway infection with mucosal involvement, or via the bloodstream when a patient has bacteremia.
pathogens: Streptococcus pneumoniae and Neisseria meningitides.
Viral – milder and short lived. Causitive agents include HSV, cytomegalovirus, enteroviruses. Most people will recover
Signs and symptoms of Meningitis
-Elevated temp
(common among CNS infection)
-Nuchal rigidity (stiffness of the neck due to meningeal irritation).
-Kernig’s sign – flexing the hip & extending the knee to elicit pain in the back & the legs
-Brudzinski’s sign – passive flexion of the neck elicits flexion of the hips
-Opisthotonos (extreme hyperextension of the head and arching of the back due to irritation of the meninges)
-Altered mental state
-Nausea, vomiting
-Headache- severe
-Photophobia (don’t like bright lights)
-Seizures
-Multiple petechiae on the body
-Non-blanchable rashes
what would be the physical assessment for meningitis
-Investigation ‘classic triad’ - nuchal rigidity, fever, and altered mental state
–Positive kernig’s or Brudzinski’s sign
–Papilloedema, photophobia
–Nausea & vomiting
–Lumbar puncture – presence of causative agent
–FBC, blood cultures, electrolyte levels
–CT scan brain
what is the pathophysiology of bacterial meningitis
Gain access to bloodstream by disabling cilia & mucosal Ig-A mediated immune protection
Bacteria is encapsulated, harder for immune system to detect
Easily cross BBB & colonise tissue
Release of bacterial toxins damage CNS structures
Inflammation induces vascular response – leads to cerebral edema
Edema causes increase of ICP,
compression, herniation & ischemia
what are the diagnostic evaluation procedures for meningitis
*Lumbar puncture to identify the causative organism in the CSF (will be Turbid)
*Blood cultures
*Physical examination
