Pain and inflammation Flashcards
List the pain mediators 6
- Bradykinin
- 5-hydroxytryptamine
- Noradrenaline
- Substance P
- Histamine
- Prostaglandin
What is pain? 4
Pain is the result of
- Inflammatory mediator activating nociceptors
- The nociceptors are in the peripheral nerves travel to dorsal horn
- Dorsal horn to spinal tract
- Spinal tract to sensory cortex
Drugs that treat pain can either be classed as? 2
- Short term management
2. Acute and chronic pain management
Short term management of pain includes? 2
- General anaesthetics
2. Local anaesthetics
Acute and chronic pain management includes? 5
- Neuropathic pain
- Anti-inflammatory drugs
- Paracetamol
- Muscle relaxants
- Opioids
Neuropathic pain is treated with ?2
- Antidepressants
2. Anticonvulsants
Anti-inflammatory drugs include? 2
- Glucocorticoids
2. NSAIDS
What are the signs of inflammation? 5
- Heat
- Redness
- Swelling
- Pain
- Loss of fucntion
Describe acute inflammation 5
This is a normal response to tissue injury caused by:
- Physical trauma
- Toxic chemicals
- Infectious organisms
- Allergens
Chronic inflammation is usually by:5
- Chronic inflammatory diseases e.g. asthma
2. Auto-immune diseases e.g. rheumatoid arthritis, inflammatory bowel disease
Describe the molecular pathway of inflammation 5
- Tissue damage
- The tissue damage activates phospholipase A2.
- Phospholipase A2 converts phospholipids into arachidonic acid
- Cycloxygenase converts arachidonic acid into inflammatory prostaglandins.
- Prostaglandins stimulate nociceptors
Explain how bronchoconstriction result from inflammation3
- Inflammation results in the production of arachidonic acid.
- Lipoxygenase converts arachidonic acid into leucotrienes
- Leucotrienes result in broncho-constriction
Describe glucocorticosteroids
Glucocorticosteroids are potent inhibitors of the inflammatory response and general immune response. They inhibit the action of phospholipase A2
What are the pharmacological actions of glucocorticosteroids 2
- Anti-inflammatory
2. Immunosuppressive agent
What are dome of the indications for use of glucocorticosteroids?3
- Asthma
- Inflammatory bowel disease
- Auto-immune disease
Glucocorticosteroids have serious adverse effect profile. What are some of the limitations? 4
Glucocorticosteroids are contraindicated in:
- Cushings syndrome
- Diabetes
- Immune suppression
- Osteoporosis
List examples of glucocorticosteroids
- Hydrocortisone
- Prednisone
- Betamethasone
Anaesthetics for short term management of pain. They can be categorized into: 2
- General anaesthetics
2. Local anesthetics
What are general anaesthetics used for? And what are they combined with?
General anaesthetics are used for surgery and are combined with opioid, benzodiazepine, neuromuscular blocker
Name 3 general anaesthetics
- Nitrous oxide
- Sevoflurane
- Halothane
What do local anaesthetics do?
Local anaesthetics reversibly block impulse conduction along the nerve axons resulting in no pain sensation.
Name a local anaesthetics
Lignocaine
What are the therapeutic uses of local anaesthetics? 6
- Spinal block anaesthesia
- Suturing
- Minor procedures
- Mouth ulcers
- Dental procedures
- Epidural anaesthesia
What is the MOA of opioids?
Opioids bind to opioid receptors which results in analgesia and sense of well being
Opioids can be described as low and high efficacy opioids. List examples 3
- Low efficacy opioid = codeine
2. High efficacy opioid = morphine, pethidine
What are the therapeutic uses of opioids?
- Analgesic
- Diarrhoea
- Anti-tussive (suppresses coughing)
What are the adverse effects of opioids?7
Central
- Respiratory depression
- Euphoria
- Sedation
- Nausea and vomiting
Peripherally
1. Constipation
What is a big problem with opioids?3
- Highly addictive
- Develop a tolerance, so need a higher dose for therapeutic benefit
- Overdose results in respiratory depression
What are the centrally acting muscle relaxants? And what do they provide?4
The centrally acting muscle relaxants provide symptomatic relief and include:
- Cyclobenzaprine
- Diazepam
- Baclofen
Describe the peripherally actin muscle relaxant. 2
Training is required to administer the peripheral muscle relaxant. This is known as botulinum toxin.
How is pain graded? 6
- Mild (3-5)
- Moderate (6-8)
- Severe (9-10)
How should you manage mild pain (3-5)?
- Paracetamol
- Weak opioid (codeine)
- NSAID
How should you manage moderate pain (6-8)?
- Paracetamol
- NSAID
- Codeine
- Stronger opioid e.g. tramadol
How should you manage severe pain (9-10)?
- PCA (IV opioid)
- Morphine / pethidine
- Paracetamol (IV)
- NSAIDS (IV/ IM)
What is allodynia?
This is a condition where a light touch produces pain
What is spontaneous dysthesias?
Shooting burning pain
Explain neuropathic pain 3
- Nerve injury results in peripheral nerve degeneration (neuroma)
- Because of the peripheral nerve degeneration, spontaneous afferent activity and spinal sensitization can result in spontaneous dysethesias
- Furthermore, spinal sensitization and Αβ afferent fibres can results in allodynia
We can manage neuropathic pain with 2
- Antidepressants
2. Anticonvulsants
Name an antidepressant used in neuropathic pain management
Amitriptilene
Name anticonvulsants used in neuropathic pain management 2
- Gabapentin
2. Pregabalin
Describe pain management in pregnancy 3
- Avoid NSAID use throughout pregnancy as it causes bleeding in the baby
- Use paracetamol monotherapy
- Short course opioids
Describe pain management in pediatrics 7
- Multimodal therapy:
- Paracetamol
- NSAIDS
- Anxiolytics (NB)
- Glucocorticosteroids
- Opioids (tilidine) NB!!
- Local anaesthetics
- Avoid aspirin
Describe pain management in migrain
- Mild: NSAID and anti-emetic
2. Severe: add triptan (vasoconstriction)
