Anaesthetics

Question 1

What is the definition of anaesthesia

Answer 1

Provision of insensibility to pain during surgical, obstetric, therapeutic and diagnostic procedures

Question 2

How do local anaesthetics work and give some examples

Answer 2

Block generation and conduction of nerve impulses at local site. remain conscious
lignocaine, bupivacaine

Question 3

Name the THREE ways of administration

Answer 3

1) Topical - nasal mucosa/wound margins
2) Infiltration - Vicinity of nerve endings and nerve trunks
3) Regional - numbing of larger area (IV)

Question 4

Explain the FOUR depths of anaesthesia

Answer 4

1 - Analgesic
consciousness not lost, thoughts blurred
2 - Excitement
Increased muscle tone, temp control, a-rhythm of EEG
respiration increased
3- Surgical anaesthesia
slow synchronised EEG, regular slow breathing, dilated
4- Medullary paralysis
loss of respiration/death

Question 5

How do we define potency of anaesthetics

Answer 5

Minimum alveolar concentration

Inhaled dose that prevents movement to a surgical stimulus

Question 6

Describe journey of inhalation anaesthetic

Answer 6

1) wash in
equilibrium between gas and anaesthetic achieved
2) uptake and distribution
High BGPC - greater amount of anaesthetic must be dissolved to equilibrate
High CO - faster removal, slower access to brain
3) brain is highly perfused rapidly achieving steady state
4) NO exiting body faster than halothane

Question 7

Propofol

• is it analgesic
• short or long acting
• any other effects

Answer 7

Short acting, decreased BP and ICP.
NO ANALGESIA
excitatory phenomena
some anti-emetic effects

Question 8

Thiopental

• is it short or long acting
• what are the side effects

Answer 8

Similar to propofol, fast acting

apnoea, coughing etc

Question 9

Etomidate

• is it analgesic
• side effects?

Answer 9

Hypnotic agent. NO ANALGESIA

little to no effects on CVS

Question 10

Ketamine

• How do you appear
• side effects

Answer 10

Unconscious but appears awake, amnesia
Increased blood pressure and cardiac output
bronchodilator (not young adults)