Anaesthetic Drugs Flashcards
1
Q
What is anaesthesia?
A
A reversible drug induced absence of sensation and awareness
2
Q
What is anaesthesia?
- Anaesthesia is any … soluble agent that causes depression of the brain in a predictable order:
- C…
- M…
- S… …
- M…
A
- Anaesthesia is any lipid soluble agent that causes depression of the brain in a predictable order:
- Cortex
- Midbrain
- Spinal cord
- Medulla
3
Q
Ethanol
- Tranquillization
- E…
- Dysarthria
- Ataxia
- S../hypnosis
- A…
- Coma
- … depression
- Death
A
- Tranquillization
- Excitation
- Dysarthria
- Ataxia
- Sedation/hypnosis
- Anaesthesia
- Coma
- Medullary depression
- Death
4
Q
History of anaesthetic drugs:
A
5
Q
How do anaesthetics work?
- Diverse range
- … solubility
- Cell membrane
- Stereo-selectivity
- Interaction with membrane proteins
- Modulation of … gated ion channels
- Global … in neuronal activity
A
- Diverse range
- Lipid solubility
- Cell membrane
- Stereo-selectivity
- Interaction with membrane proteins
- Modulation of ligand gated ion channels
- Global depression in neuronal activity
6
Q
How do anaesthetics work?
- Stimulation of … receptors
- GABAA
- Glycine
- Inhibition of … receptors
- Nicotinic
- Serotonin
- Glutamate/NMDA
A
-
Stimulation of inhibitory receptors
- GABAA
- Glycine
-
Inhibition of excitatory receptors
- Nicotinic
- Serotonin
- Glutamate/NMDA
7
Q
How do anaesthetic agents stimulate inhibitory receptors - e.g. GABA(A) receptor?
A
- GABAA
- Pentameric
- Single amino acids
- influx of Chloride ions = Hyperpolarisation
8
Q
How do we give anaesthesia?
A
- Inhale
- inject
9
Q
Inhalational agents
- …
- … oxide
- Ideal properties
- Isoflurane
- Other volatile agents
A
- Oxygen
- Nitrous oxide
- Ideal properties
- Isoflurane
- Other volatile agents
10
Q
Oxygen
A
is a drug
11
Q
Oxygen – side effects
- O2 free …
- CNS …
- Pulmonary oxygen toxicity
- Retrolental fibroplasia
- CO2 …
- Oxygen is generally … for you
A
- O2 free radicals
- CNS convulsions
- Pulmonary oxygen toxicity
- Retrolental fibroplasia
- CO2 narcosis
- Oxygen is generally good for you
12
Q
Nitrous oxide
- Odourless gas in blue cylinder
- Liq/vapour at 44bar
- Poor … MAC 105%
- Good …
- … onset/offset
- Cardio respiratory …
- Neuropathy/BM …
- 35x more soluble than N2
A
- Odourless gas in blue cylinder
- Liq/vapour at 44bar
- Poor anaesthetic MAC 105%
- Good analgesic
- Quick onset/offset
- Cardio respiratory depressant
- Neuropathy/BM depression
- 35x more soluble than N2
13
Q
Nitrous oxide is a poor … but a good …
A
Nitrous oxide is a poor anaesthetic but a good analgesic
14
Q
Physical properties of inhalational agents
- Cost
- Chemical …
- Non-…/…
- V…
- E… stable
- Effect on …
A
- Cost
- Chemical stability
- Non-flammable/explosive
- Vapourizable
- Environmentally stable
- Effect on enviroment
15
Q
Chemical properties of inhalational agents
- Non …
- … blood:gas solubility
- High … MAC
- Minimal … … (pharmacodynamics)
- Biotransformation (phamacokinetics)
- Non-…
A
- Non irritant
- Low blood:gas solubility
- High potency MAC
- Minimal side effects (pharmacodynamics)
- Biotransformation (phamacokinetics)
- Non-toxic