case 10 Flashcards
What does the Glasgow Coma Scale look at?
eye
speech
motor
What is the reticular activating system formed by?
- midbrain reticular formation
- mesencephalic nucleus
- thalamic intralaminar nucleus
- dorsal hypothalamus
- tegmentum
How can be define consciousness (in relation to neuronal activity)?
-neural activity of reticular activating system:
auditory, visual and ascending sensory tracts
What are the three phases of anaesthesia?
- induction
- maintenance
- recovery
What is the triad of general anaesthesia?
hypnosis
analgesia
muscle relaxation
What hypnotics are there?
- propofol
- barbituates
- benzodiazepines
- isoflurane (trichloethylone, halothane, enflurane)
What analgesics are there?
opiates ie fentanyl
What muscle relaxants are there?
-depolarising
suxamethonium
-non-depolarising
atracium
Which type of muscle relaxant do you need to give for intubation?
non depolarising
ie atracium
What is solubility and potency of drug? (inhalant gas)
- solubility = how it dilutes in the blood (you want it to have low solubility to be faster acting)
- potency = lipid solubility: enter membrane faster
What do you use to measure blood gas solubility (coefficient)?
Oswald coefficient
How do hypnotics work?
-disrupt synaptic transmission
(pure-synaptic membrane, altering reuptake, altering binding, altering activation/ionic conduction of postsynaptic membrane)
-direct action on neuronal plasma membrane
What do you use to measure lipid solubility and anaesthetic potency?
Meyer-Overton theory
What are the different mu receptors and what do they do?
Mu1: analgesia
Mu2: respiratory depression
Mu3: vasodilation
+ dependence, constipation, nausea, vomitting, confusion, dysphoria, meiosis
What do you use in opiate over dose?
naloxone (bids to receptor without being potent: dislodges opiate)
How does suxamethonium work?
What are the adverse effects?
- depolarising blocker: binds to ACh receptors and blocks them (very profound relaxation)
- but short acting (broken down by AChE)
AE: muscle pain, hyperkalaemia, malignant hyperthermia, anaphylaxis
How does curare/atracium work?
What are the adverse effects?
- non depolarising blocker; structurally similar to ACh –> dipoles ACh but doesn’t cause depolarisation
- long acting: competitive inhibitor, effect is concentration dependent (if increase ACh concentration, will no longer have inhibition because it will be displaced)
AE: hypotension, histamine release, wheeze, tachycardia or bradycardia, anaphylaxis, complete reversal)
How does neostigmine work? when is it given? With what is it given?
- reverse muscle relaxation: anti cholinesterase: stops breakdown of ACh: ACh builds up and start to displace the other drugs
- given with glycopyrrolate: prevents neostigmine muscarinic effects
How does propofol work?
binds oto beta subunit on GABA-A receptor
When do you use a neuropsychological assessment?
test people with known/possible neurologic or neuropsychiatric conditions
What do you test in a neuropsychological assessment?
- range of cognitive abilities/deficits that ate known to be linked to brain structures/pathways
- personal/interpersonal and contextual factors: psychological function
Why do you do a neuropsychological assessment?
- measuring cognitive defects/strength
- differential diagnosis
- guide rehab strategy
- monitor changes over time
- scientific investigation
- medico-legal evaluation
How is neuropsychological assessment carried out?
(imaging, spinal fluid, evoked potentials, vestibular functioning etc)
- basic neurological exam
- interviews, observation behavioural rating
- full measurement using standardised measures (cognitive functions including perception, memory, language and intellectual abilities)
–> rehab plan
Which cognitive functions are measured?
- perception
- memory
- language
- intellectual ability
