Case 10 - anaesthesia notes

Question 1

what is the diagram showing the scale from fully alert and conscious to brainstem death

Answer 1

Question 2

what are the different parts of the reticular activating system

Answer 2

midbrain reticular formation
mesencephalic nucleus in midbrain
thalamic intralaminar nucelus
dorsal hypothalamus
tegmentum

Question 3

reticular activating system diagram

Answer 3

Question 4

what are the phases of surgery and anaesthesia

Answer 4

preparation
induction
maintenance
early recovery
delayed recovery

Question 5

what is the monitoring of an anaesthetised patient

Answer 5

heart rate and ST segments
pulse oximetry - oxygen saturations
arterial wave form - cannula into radial artery to monitor BP and cardiac output
CO2 and ventilation perimeters
isoflurane also
temperature (hypothermic)

Question 6

how do we optimise preparation for elective surgery - physiologically

Answer 6

stop smoking, loose weight, improve exercise tolerance

Question 7

how do we optimise preparation for elective surgery - pharmacologically

Answer 7

awareness, information, anticipation and mindset

Question 8

why do people with a high BMI need more of a drug

Answer 8

because they have a lot more lipid to dissolve the drug

Question 9

what is the BIS and which range means a patient is anaesthetised

Answer 9

is the bispectral index and a number between 40 and 60 means the patient is anaesthetised

Question 10

what is local anaesthesia

Answer 10

consciousness is not impaired

Question 11

types of local anaesthesia:

Answer 11

topical
field
regional: spinal, epidural

Question 12

what is an essential feature of general anaesthetic

Answer 12

hypnosis

Question 13

what is combined anaesthesia

Answer 13

general anaesthesia combined with some regional technique

Question 14

why is anaesthesia further down the back less risky than one further up

Answer 14

because it is much easier to hit the spinal cord and do damage if anaesthesia needs to be placed higher up the back e.g epidural

Question 15

when is regional anaesthesia given

Answer 15

peripheral limbs
Lower abdomen
Supplied by a distinct set of nerves
Topical
Local infiltration
Field block
Ring blocks
plexus blocks: ultra sound guided

Question 16

what are the three components of general anaesthesia

Answer 16

hypnosis
analgesia
muscle relaxation

Question 17

what agents are used for hypnosis

Answer 17

intravenous agents: propofol, barbiturates (thiopentone), benzodiazepines

Question 18

what agents are used for analgesia

Answer 18

optiates: synthtic or natural
non-opiates

Question 19

what agents are used for muscle relaxation

Answer 19

depolarising agents
non-depolarising agents

Question 20

what is remifentanyl used for

Answer 20

to perform brain surgery when the patient is aware during it

Question 21

what do more soluble inhalation anaesthetic agents have

Answer 21

a higher coefficient

Question 22

what do agents with a lower coefficient have

Answer 22

faster onset and faster emergence

Question 23

what is the potency of anaesthetic agents measured and related to

Answer 23

measured by oil-gas partition coefficient and related to lipid solubility

Question 24

what is potency not related to

Answer 24

the blood gas solubility coefficient

Question 25

what drug has low potency

Answer 25

N2O

Question 26

what is the inverse indicator of potency

Answer 26

MAC

Question 27

what are the mode of actions these drugs can have

Answer 27

disruption of synaptic transmission Pre synaptic membrane Altering reuptake Alter binding Alter activation / ionic conductance of the post-synaptic membrane Direct action on the neuronal plasma membrane

Question 28

what is the Meyer Overton Theory

Answer 28

lipid solubility and anaesthetic potency

Question 29

what are the adverse effects

Answer 29

PONV Cardiovascular depression Negatively inotropic Variable action on heart rate arrhythmogenesis Hypotension: vasodilation Loss of airway tone: airway obstruction Malignant hyperthermia Bronchial muscle relaxation Agitation and confusion… particularly in elderly Nephrotoxicity Hepatotoxicity: halothane hepatitis

Question 30

pain pathway diagram

Answer 30

X

Question 31

what are natural opiates

Answer 31

morphine dihydro-morphine codeine

Question 32

what are opiate analogues

Answer 32

tramadol

Question 33

what are synthetic or semisynthetic agents

Answer 33

pethidine fentanyl alfentanyl remifentanyl

Question 34

what is mediated via the mu1 receptor

Answer 34

analgesia

Question 35

what is mediated via the mu2 receptor

Answer 35

respiratory depression

Question 36

what is mediated via the mu3 receptor

Answer 36

vasodilation

Question 37

where do must muscle relaxants work

Answer 37

the motor end plate

Question 38

what is a depolarising blocker

Answer 38

suxamethonium

Question 39

what are non-depolarising blockers

Answer 39

curare, atracurium

Question 40

what are the adverse effects of suxamethonium

Answer 40

muscle pain Hyperkalaemia Malignant hyperthermia Anaphylaxis Suxamethonium apnoea Increased IOP and ICP

Question 41

what are adverse effects of non-depolarising blockers

Answer 41

hypotension Histamine release Wheeze Tachycardia or bradycardia Anaphylaxis Incomplete reversal

Question 42

what drugs are involved in recovery

Answer 42

neostigmine and glycopyrolate

Question 43

what is involved in long term recovery

Answer 43

early mobilisation Physiotherapy: prevention of pulmonary complications Prevention of thromboembolic disorders Early enteral nutrition

Question 44

why are patients given 100% oxygen

Answer 44

to wash out and replace the anaesthesia gas