Analgesia sedation - Local anaesthetics Flashcards
1
Q
What is the gate theory
A
- Melzack and Wall
- C fibres lets pain through
- Ab Fibres stimulate inhibitory neurones
- Descending Pathways prevent central passage
2
Q
Fibres involved in pain modification
A
- Nociceptor C, A delta fibres
- Central Interpretation
- Not just Drugs!
3
Q
Pain score systems
A
- Linear
- Smiley/Sad Faces
- Mild Moderate Severe Excrutiating
4
Q
Pain ladder 1
A
- NSAIDS/Paracetamol
- Weak Opiates/ Local Anaesthetics
- Strong Opiates
5
Q
Pain ladder 2
A
- Strong opioids by injection, local anaesthesia
- Opioids by mouth(as pain decreases)
- Aspirin and NSAIDs
6
Q
What are opioid receptors antagonised by
A
- Naloxone
7
Q
Examples of naturally occurring opioids
A
- Morphine
- Codeine
8
Q
Example of a semi synthetic opioid
A
- Diamorphine
9
Q
Example of a synthetic opioid
A
Fentanyl
10
Q
Example of a weaker opioid
A
Codeine
11
Q
Methods of opioid administration
A
- Intravenous pca/infusion
- Intramuscular
- Oral
- Intra nasal/aerosol
- Epidural/spinal
12
Q
Locations of opioid receptors
A
- Pons and Mid brain
- Periaqueductal Grey Matter
- Nucleus Raphe Magnus
- Spinal Cord Posterior Horn 1 and 2
- G I T
- Peripheral Tissues
13
Q
Subtypes of opioid receptors
A
- MU 1 and 2 OP3
- Delta OP1
- Kappa OP2
14
Q
Side effects of morphine
A
- Respiratory Depression/Airway Loss
- Nausea and Vomiting
- Constipation/Pruritis
- Miosis
15
Q
Features of ketamine
A
- NMDA Receptors
- Kappa and delta receptors
- Not GABA
- Analgesic local/general
- Anaesthetic
- Sedative
16
Q
Side effect of ketamine
A
- Emergence phenomena
17
Q
Features of NSAIDS
A
- Act by inhibiting Cyclooxygenase 1and 2
- Analgesic, Antipyretic, Anti inflammatory
18
Q
Features of aspirin
A
- Acetylsalycilic acid
- Oxidative phosphorylation
- Air Hunger
- Reyes Syndrome
19
Q
Features of paracetamol
A
- Mechanism of Action ? Central prostaglandin effect/unknown
- Side effects
- OVERDOSE Hepatotoxicity/glutathione depletion
- N acetylcysteine
20
Q
Other analgesia
A
- Anxiolysis
- Local anaesthetics
- Antidepressants,antiepileptics,Tramadol
- Guanethadine, ketamine, clonidine
- Acupuncture
- Inhalational Nitrous oxide
- Penthrox (methoxyflurane)
- Magnesium
21
Q
Features of antiemetics
A
- Avoidance of emetics N2O Sevoflurane
- Use propofol
- Cyclizine
- Ondansetron
- Hyoscine 1944
- Metoclopromide
- Steroids
- Prochlorperazine
- cannabinoids
- People remember!
22
Q
Ramsay sedation scale
A
1 - Patient Anxious 2 - Cooperative 3 - Responds only to commands 4 - Brisk response to Glabellar Tap/Shout 5 - Sluggish Response 6 - No response
23
Q
Examples of benzodiazepines
A
- Midazolam, Diazepam, Lorazepam
24
Q
Physiology of benzodiazepines
A
- Gabba- aminobutyric Acid
- Inhibitory Neurotransmittor
- Receptors A and B
25
Side effects of benzodiazepines
- Over Sedation
- Loss of Airway
- Respiratory Depression
- ABC
- Flumazanyl with caution
- Myth of safety ,Light Anaesthesia
26
Other sedatives
- Low Dose Vapours
- Ketamine
- Hyoscine
- Propofol Low dose
- Major Tranquillisers
- Alpha 2 agonists
27
Classification of local anaesthetics
- Amides -NH.CO-
- Lignocaine,Prilocaine,Bupivacaine
- Esters –CO.O-
- Cocaine , Amethocaine
28
Mechanism of local anaesthetic action
· Na Channel Blockade
· Un- ionized Drug Through Membrane into axoplasm
· Protonated
· Blocks Channel thus blocking action potential
29
Where to put local anaesthetics
```
· Anatomy Local Blocks /Ultrasound
· Spinal Epidural Caudal
· Skin
· Aerosol/Nebulised
· Combination with GA Part of Triad
```
30
Side effects of local anaesthetics
```
· Skin/Subcutaneous
· Brachial Plexus
· Epidural
· Caudal
· Intercostal
· VESSELS AND NERVES FOLLOW EACH OTHER
```
Toxicity -
```
· CARDIOVASCULAR
· Dysrythmias,Cardiac Depression
· CENTRAL NERVOUS SYSTEM
· Fitting/Anxiety/Lossof Consciousness
· Circumoral numbness
· Ref Paper Mask 1990
```
31
Side effects of NSAIDS
Side Effects
- Gastric Irritation
- Bronchospasm
- Renal Impairment
- Platelet function ASPIRIN
