Pain

Question 1

What are the benefits of treating pain?

Answer 1

Improved sleep, better appetite 
Fewer medical complications 
Reduced suffering 
Less depression, anxiety 
Improved functioning as a family member 
Able to keep working 
Lower health costs 
Able to contribute to community

Question 2

What factors are used to classify pain?

Answer 2

Duration
Cause
Mechanism

Question 3

How is acute pain defined?

Answer 3

Pain of recent onset and probable limited duration

Question 4

How is chronic pain defined?

Answer 4

Pain lasting for more than 3 months
Pain lasting after normal healing
Often no identifiable cause

Question 5

What is the difference between cancer and non-cancer pain?

Answer 5

Progressive

May be mixture of acute and chronic

Question 6

How is nocicepetive pain described?

Answer 6

Sharp or dull

Well localised

Question 7

How is neuropathic pain described?

Answer 7

Burning, shooting +/- numbness, pins and needles

Not well localised

Question 8

What are the 4 steps in pain physiology?

Answer 8

Periphery
Spinal cord
Brain
Modulation

Question 9

What is the pathway of pain in the periphery?

Answer 9

Tissue injury
Release of chemicals (prostaglandins etc)
Stimulation of pain receptors (nociceptors)
Signal travels in A(alpha) or C nerve to spinal cord

Question 10

What is the pathway of pain in the spinal cord?

Answer 10

Dorsal horn is the first relay station
A(alpha) or C nerve synapses with second nerve
Second nerve travels up opposite side of spinal cord

Question 11

What is the pathway of pain in the brain

Answer 11

Thalamus is the second really station
Connections to many parts of the brain (cortex, limbic system, brainstem)
Pain perception occurs in the cortex

Question 12

What is the pathway of pain in modulation?

Answer 12

Descending pathway from brain to dorsal horn

Usually decreases pain signal

Question 13

What are some examples of neuropathic pain?

Answer 13

Nerve trauma, diabetic pain (damage)

Fibromyalgia, chronic tension headache (dysfunction)

Question 14

What is neuropathic pain?

Answer 14

Abnormal processing of pain signal

Question 15

What are the pathological mechanisms of pain?

Answer 15

Increased receptor numbers
Abnormal sensitisation of nerves (peripheral, central)
Chemical changes in the dorsal horn
Loss of normal inhibitory modulation

Question 16

What are some examples of simple analgesics?

Answer 16

Paracetamol (acetaminophen)

NSAIDs (diclofenac, ibuprofen)

Question 17

What are some examples of opiods?

Answer 17

Codeine
Dihydrocodeine 
Morphine 
Oxycodone 
Fentanyl

Question 18

What are some other examples of analgesics used?

Answer 18

Tramadol (mixed opiate and 5HT/NA reuptake inhibitor)
Antidepressants (amitriptyline, duloxetine)
Anticonvulsants (gabapentin)
Ketamine (NMDA receptor antagonist)
Local anaesthetic
Topical agents (capsaicin)

Question 19

What are the treatment options for peripheral pain?

Answer 19

Non-drug treatments (rest, ice, compression, elevation)
NSAIDs
Local anaesthetic

Question 20

What are the treatment options for spinal cord pain?

Answer 20

Non-drug treatments (acupuncture, massage, TENS)
Local anaesthetics
Opioids
Ketamine

Question 21

What are the treatment options for brain pain?

Answer 21

Non-drug treatments (psychological) 
Paracetamol 
Opioids 
Amitriptyline 
Clonidine

Question 22

What are the advantages of paracetamol?

Answer 22

Cheap
Safe
Can be given orally, rectally or IV
Good for mild pain (by itself) or mod-severe pain (with other drugs)

Question 23

What are the disadvantages of paracetamol?

Answer 23

Liver damage in overdose

Question 24

What are the advantages of NSAIDs?

Answer 24

Cheap
Generally safe
Good for nociceptive pain

Question 25

What are the disadvantages of NSAIDs?

Answer 25

Gastrointestinal and renal side effects plus sensitive asthmatics

Question 26

What are the advantages of codeine?

Answer 26

Cheap Safe Good for mild-mod acute nociceptive pain

Question 27

What are the disadvantages of codeine?

Answer 27

Constipation | Not good for chronic pain

Question 28

What are the advantages of tramadol?

Answer 28

Less respiratory depression Can be used with opioids and simple analgesics Not a controlled drug

Question 29

What are the disadvantages of tramadol?

Answer 29

Nausea and vomiting

Question 30

What are the advantages of morphine?

Answer 30

``` Cheap Generally safe Can be given orally, IV, IM, SC Effective if given regularly Good for mod-severe acute nociceptive pain and chronic cancer pain ```

Question 31

What are the disadvantages of morphine?

Answer 31

Constipation Respiratory depression in high dosage Misunderstandings about addiction Controlled drug

Question 32

What are the advantages of amitriptyline?

Answer 32

Cheap Safe in low doses Good for neuropathic pain Also treats depression, poor sleep

Question 33

What are the disadvantages of amitriptyline?

Answer 33

Anti-cholinergic side effects (glaucoma, urinary retention)

Question 34

What are some examples of anticonvulsant drugs?

Answer 34

Carbamazapine (Tegretol) Sodium valproate (Epilim) Gabapentin (Neurotonin)

Question 35

What are the delivery routes for medication?

Answer 35

``` Oral Rectal Sublingual Subcutaneous Transdermal Intramuscular Intravenous ```

Question 36

What are the delivery routes for local anaesthetics?

Answer 36

``` Epidural (+/- opiates) Intrathecal (+/- opiates) Wound catheters Nerve plexus catheters Local infiltration of wounds ```

Question 37

How is pain assessed?

Answer 37

``` Verbal rating score Numerical rating score Visual analogue score Smiling faces Abbey pain scale (for confused patients) ```

Question 38

What are the physical non-drug treatments?

Answer 38

``` Rest Ice Compression Elevation Surgery Acupuncture Massage Physiotherapy ```

Question 39

What are the psychological non-drug treatments?

Answer 39

Explanation Reassurance Counselling

Question 40

What is the RAT approach to pain management?

Answer 40

Recognise Assess (severity, type, other factors) Treat (drug/non-drug)

Question 41

What is the treatment for nociceptive pain?

Answer 41

Mild (paracetamol +/- NSAIDs) Moderate (paracetamol +/- NSAIDs + codeine/alternative) Severe (paracetamol +/- NSAIDs + morphine)