General Anaesthesia and Pt Management

Question 1

Use of sedation in dentistry?

Answer 1

Reduce pt anxiety

Increase acceptability or prolonged/ extensive procedures

Question 2

Use of GA?

Answer 2

Extensive or prolonger procedure or when total lack of pt co-operation (intellectual impairment/ children)

Question 3

Types of sedatives and effect?

Answer 3

1. Opiates - euphoria, nausea, respiratory depression
2. Major tranquillisers - anxiety, hypotension
3. Minor tranquilliser (benzodiazepines) - drowsiness and prolonged effect

Question 4

What is benzodiazepine and how can it be administered?

Answer 4

Minor tranquilliser
Oral - variable and small effect
IV - limited duration action need repeat dose and monitoring (SPO2 mandatory)

Question 5

Mechanism of action barbiturates/ benzodiazepines?

Answer 5

Membrane depolarisations and CNS depression - facilitate GABA action

Barbiturates increases duration Cl- channel opening
Benzodiazepine - increase frequency of channel opening

Question 6

Why are diazepam and midazlolam not used as much?

Answer 6

Diazepam - irritant, skin necrosis

Midazolam - slower onset and less predictable

Question 7

Sedation w/ propofol?

Answer 7

Act partly via GABA receptors - short acting and fast recovery
But no analgesia and need continuous infusion (expensive system)

Question 8

Characteristics of being unconscious and dangers?

Answer 8

Unrousable and loss of protective relfex

Potential for aspiration, obstruction and nerve damage

Question 9

Name IV anaesthetics and their properties?

Answer 9

1. Propofol - rapid pleasant onset and non cumulative - cause hypotension, pain on injection
2. Thiopentone - rapid onset, slow metabolism - cumulative, hypotension
3. Ketamine - rapid onset - hypertension, non cumulative, unpleasant hallucination
4. Etomidate - cardiovascular stability and none cumulative - can inhibit steroids

Question 10

Ways of maintaining airway?

Answer 10

Head position, laryngeal mask, tracheal incubation (avoid aspiration), muscle relaxants

Question 11

Example of muscle relaxant?

Answer 11

• IUM
  1. Suxamethonium
  2. Atracurium
  3. Cisatracurium
  4. Rocuronium
  5. Pancuronium

Question 12

Pre-operative assessment?

Answer 12

Maximise patient safety
Careful PMH: cardiac, respiratory ,GI, renal impairment, diabetes
Airway assessment

Question 13

Possible complications encountered during sedation?

Answer 13

Problems pre-existing disease: cardiac, respiratory, diabetes

Question 14

How to reduce complications?

Answer 14

Awareness of overdose - agent monitoring and brain function monitor 
Anaphylaxis 
Hypoxia - monitor SP02
Resp depression - CO2 monitor 
Aspiration - pre-op starving .
Haemorrhage - failing BP, suctions blood