Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

ESA 5 - Pharmacology > Anaesthetics > Flashcards

Anaesthetics Flashcards

1
Q

What are the broad categories of anasthesia?

A
  • General
  • Local
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the methods of administration of general anasthesia?

A
  • Inhalation, or volatile
  • Intravenous
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the difference in onset of action between inhalational and intravenous general anaesthesia?

A

Intravenous is quicker

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is conscious sedation?

A

The use of small amounts of anaesthetics or benzodiazepines to produce a ‘sleepy-like’ state

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the stages in general anaesthesia?

A
  1. Premedication
  2. Induction
  3. Intraoperative
  4. Muscle paralysis
  5. Maintenenance
  6. Reversal of muscle paralysis and recovery, which includes post-operative analgesia
  7. Provision for PONV
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is often used in the premedication stage of anaesthesia?

A

A hypnotic, typically benzodiazepine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How is anaesthesia induction normally performed?

A

Usually IV, but may be inhalational

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Give an example of a drug used in anaesthesia induction

A

Barbituates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What class of drug is usually used for intraoperative analgesia?

A

Opioids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the purpose of muscle paralysis in surgery?

A

To facilitate intubation/ventilation/stillness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Why is intubation important in anaesthesia?

A

Analgesia can cause respiratory depression, so you need a relaxant to allow airway access

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How is maintenance anaesthesia administered?

A

Intravenous and/or inhalation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is used for postoperative analgesia?

A
  • Opioids
  • NSAID
  • Paracetamol
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How is volatile general anaesthesia administered?

A

You fill a reservoir with the liquid drug which then evaporates. Fresh gas flows across evaporated liquid and the patient inahles it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What molecules will act as anaesthetics?

A

Any molecule with a volitile compononet

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Describe the use of xenon as an anaesthetic

A

It is a very good anaesthetic in very high concentrations, and is good in neonates to prevent cerebral ischaemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Give four examples of intravenous anaesthetic agents

A
  • Propofol
  • Barbiturates
  • Etomidate
  • Ketamine
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the stages in Guedel’s signs?

A
  • Stage 1 - Analgesia and consciousness
  • Stage 2 - Unconscious, breathing erratic. Delirium could occur, leading to an excitement phase
  • Stage 3 - Surgical anaesthesia
  • Stage 4 - Respiratory paralysis and death
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Describe the muscle tone in Guedel’s stage 1

A

Normal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Describe the eye movements in Guedel’s stage 1

A

Slight

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

How long does Guedel’s stage one last?

A

Only the first few breaths

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Describe the muscle tone in Guedel’s stage 2

A

Normal to markedly increased

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Describe the eye movements in Guedel’s stage 2

A

Moderate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Describe the muscle tone in Guedel’s stage 3

A

Progresses from slightly relaxed to markedly relaxed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Describe the eye movements in Guedel's stage 3
Progresses from slight to none
26
Describe breathing in Guedel's stage 3
Decreases until significantly reduced respiratory effort
27
What are the options once a patient reaches Guedel's stage 4?
* Wake patient * Ventilate the patient
28
What is anasthesia a combination of?
* Analgesia * Hyponosis * Depression of spinal reflexes * Muscle relaxation
29
What is the end point of anasthesia dependant on?
Concentration
30
In what order to functions go under anaesthesia?
1. Memory 2. Consciousness 3. Movement 4. Cardiovascular response
31
What measure is used to describe potency for volatile anaesthetics?
MAC - Minimum Alveolar Concentration
32
What is MAC?
The alveolar concentration of the anaesthetic at which 50% of subjects fail to move to surgical stimulus
33
What is the alveolar concentration of anaesthetic equal to at equilibrium?
The concentration of anaesthetic in the spinal cord
34
What is the anatomical substrate for MAC?
The spinal cord
35
What important factor affects induction and recovery?
The partition coefficients (solubility)
36
What are the potential partitions in anaesthetics?
* Blood:gas partition * Oil:gas partition
37
What does the blood:gas partition coefficient measure?
The solubility of gas in the blood
38
What effect does a low blood:gas partition have on induction and recovery?
Means it will be fast
39
What does the oil:gas coefficient measure?
The solubility of gas in fat
40
What does the oil:gas partition coefficient determine?
The potency
41
Why does the oil:gas partition coefficient determine potency?
Because target sites are in membranes
42
What factors affect MAC?
* Age * Body temperature * Pregnancy * Alcoholism * Central stimulants * Other anaesthetics and sedatives * Opiods
43
How does age affect MAC?
It is high in infants, and low in the elderly
44
How does body temperature affect MAC?
It is increased in hyperthermia and decreased in hypothermia
45
How does pregnancy affect MAC?
Increases it
46
How does alcoholism affect MAC?
Increases it
47
How do central stimulants affect MAC?
Increase it
48
How do other anaesthetics and sedatives affect MAC?
Decrease it
49
How do opiods affect MAC?
Decrease it
50
How does administering anaesthetic agents with nitrous oxide affect MAC?
Significantly reduced
51
What is the advantage of reducing MAC using nitrous oxide?
Can provide an extra window of safety
52
Other than lipid solubility, what does anaesthetic potency correlate to?
GABAA activity
53
What is GABAA?
A major inhibitory neurotransmitter
54
What kind of receptor is the GABAA receptor?
Ligand gated ion channel
55
What happens when GABAA binds to its receptor?
It causes the opening of the ion channel, allowing flow of Na+ and therefore the membrane becomes more difficult to excite, leading to CNS depression
56
What are the effects of GABAA receptor activation?
* Anxiolysis * Sedation * Anaesthesia
57
Which anaesthetics potentiate GABAA mediated Cl- conductance to depress CNS activity?
All except for Xe, N2O and ketamine
58
What receptors do Xe, N2O and ketamine act on?
Probably NMDA receptors
59
What balance exists in the conscious brain?
Excitation (glutamate) and inhibition (GABA)
60
What effect do anaesthetics have on the balance in the brain?
They modulate it
61
What effect do anaesthetics have on brain structures?
* Reticular formation (hindbrain, midbrain, and thalamus) are depressed * Hippocampus depressed, *reducing memory* * Brainstem depressed, *reducing respiratory and some CVS functions* * The dorsal horn of the spinal cord is depressed in analgesia * The motor neuronal activity of the spinal cord is depressed with MAC
62
What does the reticular system normally do?
Increase arousal, *hence it is called the activating system*
63
What does the thalamus normally do?
Transmits and modifies sensory information
64
What are the main intravenous anaesthetics?
* Propofol * Barbiturates * Ketamine
65
What is the use of intravenous anaesthetics?
* Induction * Can be used as the sole anaesthetic in TIVA (**T**otal **I**ntra**v**enous **A**naesthesia)
66
What happens in TIVA?
An infusion pump continues adminsteration, *typically using propofol*
67
How is intravenous anaesthetic potency described?
As the plasma concentration to acheive a specific end point, *e.g. loss of eyelash reflex, BIS value*
68
What is the end point used to determine in mixed anaesthesia?
The point at which to switch to volatile anaesthesia after induction
69
How does TIVA determine what dose to be giving?
It uses a defined PK based algorithm to infuse at a rate to maintain the set point
70
What are the uses of local and regional anaesthetics?
* Dentisty * Obstetrics * Regional surgery * Post-op * Chronic pain management
71
Give 4 examples of local anaesthetics
* Lidocaide * Bupivacaine * Ropivacaine * Procaine
72
What factors determine the characterstics of local anaesthetics?
* Lipid solubility * Dissociation constant * Chemical link * Protein binding
73
What does the solubility of local anaesthetics determine?
The potency - *the higher the lipid solubility, the higher the potency*
74
What does the dissocation constant determine in local anaesthetics?
The time of onset - *lower the pKa, the faster the onset*
75
What does the chemical link determine in local anaesthetics?
The rate of metabolism - *ester links don't last as long, as tissues possess lots of esterases, whereas amides last longer*
76
What does protein binding effect in local anaesthetics?
Duration - *the more the binding, the longer the duration*
77
What is regional anaesthesia?
Selectively anaesthetising a part of the body
78
What is regional anaesthesia often described as?
A 'block' of a nerve
79
What agents to regional anaesthetics use?
A local anaesthetic, with or without an opiod
80
What are the sites of regional anaesthesia in the upper extremity?
* Interscalene * Supraclavicular * Infraclavicular * Axillary
81
What are the sites of reginal anaesthesia in the lower extremity?
* Femoral, sciatic, popliteal, saphenous
82
What regional anaesthetics are used in labour?
* Extradural * Intrathecal * Combined
83
What are the main side effects of general anesthesia?
* PONV *(with opiods)* * Hypotension * Post-operative cognitive dysfunction * Chest infection
84
What increases the risk of post-operative cognitive dysfunction?
Increasing age
85
What do side effects of local and regional anaesthesia usually result from?
Systemic spread
86
What might result in systemic spread of anaesthetics?
* Wrong dose * Wrong site of administration
87
Give an example of a systemic side effect of local anaesthetics
Cardiovascular toxicity, *as locals are sodium channel blockers*
88

ESA 5 - Pharmacology (28 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions