Anaesthesia

Question 1

What is tidal volume

Answer 1

Volume of gas exhaled in one breath
10-15ml/kg x BW

Question 2

What is minute volume

Answer 2

Volume of gas expired in one minute
TV x RR

Question 3

Anatomical and equipment dead space

Answer 3

Volume of gas that is not involved in gas exchange
Anatomical- doesn’t reach alveoli
Equipment- in breathing circuit

Question 4

What is neuroleptanalgesia

Answer 4

Combo of opioid and sedative to produce calm and pain reduced state

Question 5

Anaesthesia sparing effect

Answer 5

Use of other agents or drugs to reduce amount of volatile agent needed

Question 6

Second gas effect

Answer 6

Giving nitrous oxide to speed uptake of volatile agent

Question 7

What is critical tension

Answer 7

Rise in anaesthetic agents in the blood that affects the brain

Question 8

What is BG solubility coefficient

Answer 8

How likely agent is to dissolve in the blood (low does not dissolve easy and reaches brain quicker)
Sevo- low
ISO- high

Question 9

What is the MAC

Answer 9

Minimum alveolar concentration- % concentration of agent in the alveoli for patient to the anaesthetised
Low MAC = more potent, high solubility

Question 10

How are anaesthetic agents removed from the body

Answer 10

Exhalation
Metabolised by kidneys and liver
Excreted in bile and urine

Question 11

4 responses to pain

Answer 11

Spinal- limb withdrawal
Medullary - increases HR, RR, BP
Hypothalamic- hormone release
Cortical- physical acts

Question 12

What is balanced anaesthesia

Answer 12

Use of multiple drugs in combo to provide anaesthesia triad
Individual doses reduced and reduced drug effects

Question 13

Triad of anaesthesia

Answer 13

1. Narcosis
2. Analgesia
3. Muscle relaxation

Question 14

Aims of pre med

Answer 14

Smoother induction and recovery
Sedation
Analgesia
Reduces anaesthetic doses
Counter effects of other drugs

Question 15

4 methods to maintain anaesthesia

Answer 15

1. Injectables alone
2. Inhalation alone
3. TIVA
4. PIVA

Question 16

Inhalation agents

Answer 16

Liquid at room temp (not N2O)- vaporised into gas
Mixed with carrier gas - N2O, O2, medical air
Iso, sevo, des

Question 17

Injectables

Answer 17

Use of injectables
IV or IM
Alpha 2s, ketamine, opioids, benzos

Question 18

TIVA

Answer 18

Total IV agents
CRI or incremental
Need to combine with analgesia
Propofol, alfaxalone, ketamine

Question 19

PIVA

Answer 19

Partial IV
Mix of inhalation and injectable
CRI or incremental
Lidocaine (not for cats), opioids, ketamine

Question 20

Neuromuscular blockage

Answer 20

Agents cause muscle relaxation
Need IPPV , analgesia, unconsciousness
Blocks action potential at NJM
Depolarising or non depolarising
Monitor with peripheral nerve stimulator

Question 21

FGF formula

Answer 21

FGF rate= minute volume x circuit factor

Question 22

Non rebreathing circuits

Answer 22

T piece
Bain
Lack
Magill
Humphrey ADE

Question 23

Re breathing circuits

Answer 23

Circle
To and fro
Humphrey ADE circle

Question 24

T piece circuit factor

Answer 24

2.5-3

Question 25

Bain circuit factor

Answer 25

2.5-3

Question 26

Lack circuit factor

Answer 26

1-1.5

Question 27

Magill circuit factor

Answer 27

1-1.5

Question 28

FGF calculation

Answer 28

1. TV = 10-15mg/kg x BW
2. MV= TV x RR
3. FGF= MV x CF