ANAESTHESIA

Question 1

name the 5 stages of surgery

Answer 1

preparation
induction
maintenance
early recovery
late recovery

Question 2

name 3 ways in which a patient should be prepared for general anaesthesia…

Answer 2

physiological
psychological
pharmacological

Question 3

if an induction agent has a low oswalds coefficient, what would you expect to be the speed of onset and duration of action?

Answer 3

low coefficient = low solubility

low solubility = increased availability of drug in CNS, adequate partial pressures reached quickly

= Short speed of onset and duration of action

Question 4

if an induction agent has a high oswalds coefficient, what would you expect to be the speed of onset and duration of action?

Answer 4

high coefficient = very soluble

high solubility = not much drug around to develop adequate partial pressures in CNS

= slow speed of onset and duration of action

Question 5

potency of an anaesthic agent is determined by what?

Answer 5

the rate at which it dissolves in fatty tissue

Question 6

where does the descending inhibitory pain pathway start?

Answer 6

periaqueductal gray matter

Question 7

what are the natural opiates (3)?

Answer 7

morphine
dihydro-morphine
codeine

Question 8

name a synthetic morphine analogue

Answer 8

tramadol

Question 9

name 4 synthetic opiates

Answer 9

remifentanil
alfentinal
fentinal
pethidine

Question 10

activation of mu1 receptors causes what physiological response?

Answer 10

analgesia

Question 11

activation of mu2 receptors causes what physiological response?

Answer 11

respiratory depression

Question 12

activation of mu3 receptors causes what physiological response?

Answer 12

vasodilation

Question 13

what drug is an opioid receptor antagonist?

Answer 13

naloxone

Question 14

what are the side effects of non-depolarising NMJ blockers?

Answer 14

hypotension
histamine release
tachycardia/bradycardia
incomplete reversal

Question 15

what are the side effects of depolarising NMJ blockers?

Answer 15

muscle pain
hyperkalaemia
malignant hyperthermia
sux apnoea

Question 16

what is the breakdown of eye response in GCS?

Answer 16

WORTH 4 POINTS

opens spontaneously 4
opens to sound 3
opens to pain 2
doesn’t open 1

Question 17

what is the breakdown of verbal response in GCS?

Answer 17

WORTH 5

communicates clearly 5
confused 4
inappropriate words 3 
random sounds 2 
no speech 1

Question 18

what is the breakdown of motor response in GCS?

Answer 18

6 POINTS

obeys command 6
localises to pain 5
normal flexion to pain 4
abnormal flexion to pain 3
extension to pain 2
no movement 1

Question 19

what 2 cranial nerves are most commonly injured in acute head trauma?

Answer 19

trochlear
olfactory

(oculomotor secondary damage via uncal herniation)

Question 20

what are the criteria for a CT scan within 1 hour of admission with acute head trauma?

Answer 20

GCS less than 13
open/depressed fracture
any sign of basal skull fracture
seizures
vomitting

Question 21

what are the criteria for a CT scan within 8 hours of admission with acute head trauma?

Answer 21

amnesia
over 65
history of bleeding

Question 22

what is battles sign?

Answer 22

post-aurciular bleeding indiciates basal skull fracture

Question 23

what are racoon eyes?

Answer 23

bilateral peri-orbital haematoma

Question 24

what is the most common cause of an extradural haematoma?

Answer 24

damage to middle meningeal artery that runs between periosteum and dura mater

Question 25

what is the most common cause of subdural haematoma?

Answer 25

damage to bridging veins that run between dura and arachnoid mater

Question 26

how can extradural and subdural haematoma be disinguished via MRI?

Answer 26

sub-dural haematoma follows contours of gyri/sulci

Question 27

how do extra-dural haematomas usually present?

Answer 27

acute- pt mainly symptomatic (during tamponade of blood between dura and skull)
peri-acute - ICP raises enough so that dura is pulled away from the skull. haemorhage speads and pt deteriorates

Question 28

how do sub-dural haemorhages usually present?

Answer 28

progressive deterioration following head injury, leakage of venous blood into dural sinuses

Question 29

what is normal ICP?

Answer 29

15mmHg

Question 30

how is cerebral perfusion pressure calculated?

Answer 30

mean arterial pressure - ICP

Question 31

what is the consequence of ICP being higher than MAP?

Answer 31

decrease in cerebral blood flow

Question 32

what is the kelly munroe doctrine?

Answer 32

CSF and intracerebral blood flow are constant.

an increase in ICP causes a reciprocal decrease in cerebral blood flow.

This manages the problem of having a skull with a fixed volume

there are two phases; compensating and decompensating

Question 33

what are the two types of ischaemia?

Answer 33

cytotoxic - fluid in cytoplasmic due to loss of ion gradients across cells
vasogenic - delayed, due to breakdown of blood brain barrier

Question 34

how would you treat raised ICP? (5 things)

Answer 34

mannitol/furosemide
head position at 30 degrees
avoid hypoxia
mechanical hyperventilation
hypothermia

Question 35

how does mechanical hyperventilation help reduce ICP?

Answer 35

induces cerebral vasoconstriction, reducing blood flow to brain, hence volume reduces, and lowers ICP

Question 36

what are the 4 stages of sleep?

Answer 36

stage 1
stage 2
slow wave
REM sleep

Question 37

what is the role of melatonin in sleep?

Answer 37

Suprachiasmatic nucleus responds to light stimuli causing pineal gland to secrete melatonin, this occurs 2-3 hours before bedtime

Question 38

what is the function of the tuberomamillary nucleus in sleep?

Answer 38

secretes histamine to promote wakefulness

Question 39

what is the function of the venterolateral preoptic neurones in sleep?

Answer 39

promotes sleep

Question 40

what are the 4 parts of the neuropsychological assessment?

Answer 40

perception - how sensory input is perceived

memory

language

intellectual abilities