T1 L24 Analgesics, anaesthetic & sedation drugs

Question 1

What is pain?

Answer 1

Unpleasant sensory & emotional experience associated with actual or potential tissue damage

Question 2

Describe gate theory

Answer 2

C fibres let pain through
AB fibres stimulate inhibitory neurons
Descending pathways prevent central passage

Question 3

Describe pain modification

Answer 3

Nociceptor C
A delta fibes
Central interpretation
Not just drugs

Question 4

How can pain be scored?

Answer 4

Linear
Smiley / sad faces
Mild, moderate, severe, excruciating

Question 5

Describe the WHO analgesic ladder

Answer 5

Aspirin & NSAIDs
Add local anaesthetic & weak opioids
Add strong opioids

Question 6

Describe the WFSA analgesic ladder

Answer 6

Aspirin & NSAIDs
Opioids by mouth
Strong opioids by injection, local anaesthesia

Question 7

Where do opioids act?

Answer 7

On opioid receptor

Question 8

What antagonises opioids?

Answer 8

Naloxone

Question 9

What are examples of naturally occurring opioids?

Answer 9

Morphine

Codeine (weaker)

Question 10

Give example of a semi-synthetic opioid

Answer 10

Diamorphine

Question 11

Give an example of a synthetic opioid

Answer 11

Fentanyl

Question 12

How can opioids be administered?

Answer 12

Intravenous / infusion
Intramuscular
Oral
Intranasal / aerosol
Epidural / spinal

Question 13

Where are opioid receptors located?

Answer 13

Pons & midbrain
Periaqueductal grey matter
Nucleus raphe Magnus 
Spinal cord posterior horn 1 & 2
GI tract
Peripheral tissues

Question 14

What are the subtypes of opioid receptors?

Answer 14

MU 1 & 2
OP3
Delta - OP1
Kappa - OP2

Question 15

What are the side effects of morphine?

Answer 15

Respiratory depression / airway loss
Nausea / vomiting
Constipation / pruritus
Miosis

Question 16

Describe ketamine

Answer 16

NMDA antagonist
Kappa & delta receptors
Analgesic local / general
Anaesthetic
Sedative
Side effects: emergence phenomena

Question 17

Describe NSAIDs

Answer 17

Inhibit cyclooxyrgenase 1 & 2
Analgesic
Antipyretic
Anti-inflammatory

Question 18

What are the side effects of NSAIDs?

Answer 18

Gastric irritation
Bronchospasm
Renal impairment
Platelet function - aspirin

Question 19

Describe aspirin

Answer 19

Acetylsalicylic acid
Oxidative phosphorylation
Air hunger
Reyes syndrome

Question 20

Describe paracetamol

Answer 20

Mechanism is unknown

Central prostaglandin effect

Question 21

What are the effects of an overdose of paracetamol?

Answer 21

Hepatotoxicity

Glutathione depletion

Question 22

What are some other methods of analgesia?

Answer 22

Anxiolysis
Local anaesthetics
Antidepressants, anti epileptics, tramadol
Guanethadine, ketamine, clonidine
Acupuncture
Inhalation nitrous oxide
Penthrox
Magnesium

Question 23

What is used as an anti-emetic?

Answer 23

Propofol
Cyclizine
Ondansetron
Hyoscine
Metoclopramide
Steroids
Prochlorperazine
Cannabinoids

Question 24

Describe the Ramsay sedation scale

Answer 24

Patient anxious
Cooperative
Responds only to commands
Brisk response to Glabellar tap / shout
Sluggish response
No response

Question 25

Give examples of some benzodiazepines

Answer 25

Midazolam Diazepam Lorazepam

Question 26

Describe the physiology of benzodiazepines

Answer 26

GABA Inhibitory neurotransmitter Receptors A & B

Question 27

Describe the side effects of benzodiazepines

Answer 27

Over-sedation Loss of airway Respiratory depression

Question 28

What can be given to reduce side effects of benzodiazepines?

Answer 28

Flumazenil

Question 29

Give examples of some other sedatives

Answer 29

``` Low dose vapours Ketamine Hyoscine Propofol at low dose Major tranquilisers Alpha 2 agonists ```

Question 30

What are the categories of other sedatives?

Answer 30

Amides | Esters

Question 31

Give an example of an amide sedative

Answer 31

Lignocaine Prilocaine Bupivacaine

Question 32

Give an example of an ester sedative

Answer 32

Cocaine | Amethocaine

Question 33

Give examples of the mechanisms of other sedatives

Answer 33

Na channel blockade Un-ionised drug through membrane into axoplasm Protonated Blocks channel --> blocks action potential

Question 34

Methods of administering sedatives

Answer 34

``` Anatomy local blocks / ultrasound Spinal epidural caudal skin Aerosol / nebulised Combination with GA ```

Question 35

What are some cardiovascular symptoms of toxicity?

Answer 35

Dysrhythmias | Cardiac depression

Question 36

What are some central nervous system symptoms of toxicity?

Answer 36

Fitting Anxiety Loss of consciousness Circumoral numbness

Question 37

What is the treatment for toxicity?

Answer 37

ABC Oxygen Lipid - 20% Dysrhythmias / fitting