General Anaesthesia

Question 1

What is the definition of anaesthesia?

Answer 1

Anaesthesia is the reversible loss of response to noxious stimuli.

Question 2

What is general anaesthesia?

Answer 2

General anaesthesia is when anaesthesia is associated with loss of consciousness.

Question 3

What is a general anaesthetic?

Answer 3

A general anaesthetic is a drug that brings about reversible loss of consciousness.

Question 4

Who administers general anaesthetics?

Answer 4

General anaesthetics are administered by an anaesthesiologist.

Question 5

Name the stages of anaesthesia.

Answer 5

The stages of anaesthesia are Stage I, Stage II, Stage III, and Stage IV.

Question 6

Describe Stage I of anaesthesia.

Answer 6

Stage I is Analgesia.

Question 7

Describe Stage II of anaesthesia.

Answer 7

Stage II is Excitement, a dangerous state with combative behaviour.

Question 8

Describe Stage III of anaesthesia.

Answer 8

Stage III is Surgical anaesthesia.

Question 9

Describe Stage IV of anaesthesia.

Answer 9

Stage IV is Medullary paralysis where respiratory and vasomotor control ceases.

Question 10

What are the planes of Stage III anaesthesia?

Answer 10

The planes of Stage III anaesthesia are Plane 1, Plane 2, Plane 3, and Plane 4.

Question 11

What happens during Plane 1 of Stage III anaesthesia?

Answer 11

In Plane 1, there are roving movements of the eyeballs.

Question 12

What happens during Plane 2 of Stage III anaesthesia?

Answer 12

In Plane 2, there is progressive loss of corneal, blink, and eyelid reflexes.

Question 13

What happens during Plane 3 of Stage III anaesthesia?

Answer 13

In Plane 3, pupils start dilating, and muscle relaxation occurs.

Question 14

What happens during Plane 4 of Stage III anaesthesia?

Answer 14

In Plane 4, only abdominal/diaphragmatic respiration remains, and pupils are fully dilated.

Question 15

How is anaesthesia classified?

Answer 15

Anaesthesia is classified into inhalational and intravenous types.

Question 16

What are the two main types of anaesthesia?

Answer 16

The two main types are inhalational and intravenous anaesthesia.

Question 17

Name the types of inhalational anaesthetics.

Answer 17

Inhalational anaesthetics include non-halogenated (nitrous oxide) and halogenated (halothane, isoflurane, desflurane, enflurane, sevoflurane).

Question 18

What is balanced anaesthesia?

Answer 18

Balanced anaesthesia uses a combination of drugs to achieve different anaesthetic effects.

Question 19

What are the components of balanced anaesthesia?

Answer 19

The components of balanced anaesthesia are unconsciousness, analgesia, muscle relaxation, and reflex abolition.

Question 20

Name the non-halogenated inhalational anaesthetic.

Answer 20

Nitrous oxide is the non-halogenated inhalational anaesthetic.

Question 21

Name the halogenated inhalational anaesthetics.

Answer 21

Halogenated inhalational anaesthetics are halothane, isoflurane, desflurane, enflurane, and sevoflurane.

Question 22

What is the Minimum Alveolar Concentration (MAC)?

Answer 22

The MAC is the minimum alveolar concentration of an anaesthetic agent that produces immobility in 50% of patients exposed to a standard noxious stimulus.

Question 23

What factors decrease MAC?

Answer 23

Factors that decrease MAC include hypothermia, hyponatremia, pregnancy, old age, and severe anaemia.

Question 24

What factors increase MAC?

Answer 24

Factors that increase MAC include hyperthermia, hypernatremia, and CNS stimulants.

Question 25

What determines the depth of anaesthesia?

Answer 25

The depth of anaesthesia depends primarily on the partial pressure of the anaesthetic in the brain.

Question 26

How does solubility in blood affect anaesthesia induction and recovery?

Answer 26

Low solubility in blood results in fast induction and recovery, while high solubility results in slower induction and recovery.

Question 27

List the factors that determine anaesthetic depth.

Answer 27

Factors determining anaesthetic depth include inspired concentration, alveolar ventilation, solubility in blood, solubility in tissues, and cardiac output.

Question 28

What are the characteristics of the ideal inhalational agent?

Answer 28

The ideal inhalational agent is non-irritant, chemically stable, non-flammable, and produces unconsciousness, analgesia, and muscle relaxation.

Question 29

What is nitrous oxide commonly known as?

Answer 29

Nitrous oxide is commonly known as laughing gas.

Question 30

What are the advantages of nitrous oxide?

Answer 30

Advantages of nitrous oxide include non-flammability, non-irritant properties, potent analgesic effects, rapid onset, and minimal toxicity.

Question 31

What are the disadvantages of nitrous oxide?

Answer 31

Disadvantages of nitrous oxide include weak anaesthetic potency, no muscle relaxation, and the risk of diffusion hypoxia.

Question 32

What is halothane used for?

Answer 32

Halothane is used for the induction and maintenance of anaesthesia.

Question 33

What are the effects of halothane on the cardiovascular system?

Answer 33

Halothane reduces arterial blood pressure and causes coronary artery vasodilation.

Question 34

What are the effects of halothane on the respiratory system?

Answer 34

Halothane causes rapid, shallow breathing, decreases alveolar ventilation, and is a potent bronchodilator.

Question 35

Name two common inhalational agents used in paediatric anaesthesia.

Answer 35

Halothane and sevoflurane are commonly used inhalational agents in paediatric anaesthesia.