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1
Q

what is the definition of pain?

A

Pain is “an unpleasant sensory and emotional experience associated with or resembling that associated with actual or potential tissue damage, or described in terms of such damage”

2
Q

Six Key notes in latest revision of pain definition 2020, what are they?

A
  • Pain is a personal experience influence by biological, psychological and social factors
  • Pain and nociception are different phenomena
  • Individuals learn the concept of pain through life experiences
  • A person’s report of pain should be respected
  • Pain serves an adaptive role but may have adverse effects on function and psychological well being
  • Verbal description is only one of several behaviours to express pain
3
Q

why should we bother to treat pain?

A
  • 1 in 4 people live with persistent pain
  • Basic Human Right
  • 66% of people attending A & E seeking help with pain had made around 3 visits to HCP in proceeding weeks
  • Person living with pain has poor quality of life as bad as other neurological diseases
  • Low Back Pain is the number 1 disease for years lost to disability worldwide
4
Q

what are the physical benefits to the patient of treating pain?

A
  • Improved sleep, better appetite
  • Fewer medical complications (e.g. heart attack, pneumonia)
5
Q

what are the phycological benefits of treating pain for a patient?

A
  • Reduced suffering
  • Less depression, anxiety
6
Q

what are the befits of treating pain for the family?

A

Improved functioning as a family member (e.g. as a father or mother)

Able to keep working

7
Q

whata re the benefits of treating pain for society?

A

lower health costs (e.g. shorter hospital stay)

able ot contribute to the community

8
Q

Classification of pain:

whata r ethe different classifications of pain in relation to duration?

A

Acute

Chronic

Acute on chronic

9
Q

Classification of pain:

what ar ethe different classifications of pain in relation ot the cause?

A

cancer

non-cancer

10
Q

Classification of pain:

what are the different classifications of pain in regards to the mechanism? (maybe ht emost useful classification)

A

Nociceptive

Neuropathic

11
Q

what is acute pain?

A

Pain of recent onset and probable limited duration

12
Q

what is chronic pain?

A

Pain lasting for more than 3 months

Pain lasting after normal healing

Often no identifiable cause

13
Q

what is cancer pain like?

A

Progressive

May be mixture of acute and chronic

14
Q

what is non-cancer pain like?

A

Many different causes

Acute or chronic

15
Q

what is nociceptive pain?

A

obvious tissue injury or illness

Also called physiological or inflammatory pain

serves a protective function

Description of the pain may be sharp +/- dull and also weill be well localised

16
Q

what is neuropathic pain?

A
  • Nervous system damage or abnormality
  • Tissue injury may not be obvious (Pain going on long after the original injury if there is an injury at all)
  • Does not have a protective function
  • Description:
  • Burning, shooting ± numbness, pins and needles
  • Not well localised
17
Q

the physiology of pain is made up by 4 steps, what are they?

A

Periphery

Spinal cord

Brain

Modulation (a descending pathway to switch of the pain pathway into the dorsal horn)

4 basic steps that result in the experience of pain for the patient

18
Q

as part of the physiology of pain, the first step is the periphary, what happens here to start the pathway of pain?

A
  • Tissue injury
  • Release of chemicals e.g. Prostaglandins, Substance P
  • Stimulation of pain receptors (nociceptors)
  • Signal travels in Aδ or C nerve to spinal cord (Dorsal route ganglion of the spinal cord)
19
Q

as part of the physiology of pain, the second step is the spinal cord, how is it involved in this pathway?

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

spinothalamic tract

20
Q

as part of the physiology of pain, the third step is the brain, how is it involved in this pathway?

A
  • Thalamus is the second relay station
  • Connections to many parts of the brain
  • Cortex
  • Limbic system
  • Brainstem

•Pain perception occurs in the cortex

21
Q

as part of the physiology of pain, the fourth step is the modulation, how is it involved in this pathway?

A
  • Descending pathway from brain to dorsal horn
  • Usually decreases pain signal

Done through many different types of neurotransmitters

22
Q

one type of modulation is the gate theory, what is it?

A

Rubbing or massaging activated an inhibiting neurone to switch of the nociceptive afferent signal from going into the dorsal horn

23
Q

what is the cause of neuropathic pain an dhow does it need to be treated?

A
  • Abnormal processing of pain signal
  • Nervous system damage or dysfunction
  • Needs to be treated differently (from nociceptive pain)
  • Examples:
  • Nerve trauma, diabetic pain (damage – ischemic damage)
  • Fibromyalgia, chronic tension headache (dysfunction)
24
Q

what is the pathological mechanisms of neuropathic pain?

A
  • Increased receptor numbers (enhance pain signal and keeps it going for longer)
  • Abnormal sensitisation of nerves
  • Peripheral
  • Central
  • Chemical changes in the dorsal horn
  • Loss of normal inhibitory modulation (from descending pathways)
25
Q

what are the main drug classifications and examples of each?

A

•Simple analgesics:

  • Paracetamol (acetaminophen)
  • Non-Steroidal Anti-inflammatory drugs - Diclofenac, Ibuprofen

•Opioids:

  • Weak: Codeine, Dihydrocodeine, Tramadol
  • Strong: Morphine, Oxycodone, Fentanyl

(Note that both weak and strong opioids have the potential for addiction)

26
Q

whata re some otehr analgesics?

A
  • Tramadol (Mixed opiate and 5HT/NA reuptake inhibitor)
  • Antidepressants (e.g. amitriptyline, duloxetine)
  • Anticonvulsants (e.g. gabapentin)
  • Ketamine (NMDA Receptor antagonist)
  • Local anaesthetics
  • Topical agents (e.g. Capsaicin)
27
Q

what are some treatments that can be used to affect the periphery?

A
  • Non-drug treatments - Rest, ice, elevation
  • Non-steroidal Anti-inflammatory drugs
  • Local anaesthetics
28
Q

what are some treatments that can be used to affect the spinal cord?

A
  • Non-drug treatments - Acupuncture, massage, TENS (utilizing gate theory of pain)
  • Local anaesthetics
  • Opioids
  • Ketamine
29
Q

what are some treatments you can use that can affect the brain?

A
  • Non-drug treatments - Psychological
  • Drug treatments:
  • Paracetamol
  • Opioids
  • Amitriptyline
  • Clonidine
30
Q

what are the advantages of paracetamol?

A

Cheap, safe

Can be given orally, rectally or intravenously

Good for:

  • Mild pain (by itself)
  • Mod-severe pain (with other drugs)
31
Q

what are the disadvantages of paracetamol?

A

Liver damage in overdose (Maximum is according to the weight of the patient)

32
Q

what are some examples of Non-Steroidal Anti-Inflammatory Drugs?

A

•Aspirin, ibuprofen, diclofenac

33
Q

what are the advantages of NSAIDS?

A

Cheap, generally safe

Good for nociceptive pain:

•Best given regularly with paracetamol (Synergism)

34
Q

what are the disadvantages of NSAIDS?

A

Gastrointestinal and renal side effects plus bronchospasm in some patients with asthma

Can reduce renal blood flow

When prescribing make sure patient has had them before in the past and got on alright with them

35
Q

what are the advantages of codeine?

A

Cheap, safe

Good for mild-moderate acute nociceptive pain:

•Best given regularly with paracetamol

36
Q

what are the disadvantages of codeine?

A

Constipation

Not good for neuropathic pain (same with most of the opiods)

37
Q

what effect does tramadol have?

A

•Weak opioid effect plus inhibitor of serotonin and noradrenaline reuptake (modulation)

38
Q

what are the advantages of tramadol?

A

Less respiratory depression

Can be used with opioids and simple analgesics

Less constipating than opioids

39
Q

what are the disadvantages of tramadol?

A

Nausea and vomiting, controlled drug

Can be poorly tolerated by some patients and especially higher doses

40
Q

whata re the advantages of morphine?

A

Cheap, generally safe

Can be given orally, IV, IM, SC, PR, Intrathecally

Effective if given regularly

Good for:

  • Mod-severe nociceptive pain (e.g. post-op pain)
  • Cancer Pain

Not advised for neuropathic pain (If mix of both types of pain then it can be useful but not only for neuropathic pain)

41
Q

what are the disadvantages of morphine?

A

Constipation

Respiratory depression in high dose

Addiction and avoidance due to fear of addiction

Controlled drug

42
Q

Oral dose needs to be increased if changing from IV/ IM or S/C routes, why is this?

A

as third pass metabolism reduces the amount of morphine available (when taken orally)

43
Q

what does Amitriptyline do?

A
  • Tricyclic antidepressant (TCA)
  • Increases descending inhibitory signals (to modulate the pain pathway)
44
Q

what are the advantages of amitriptyline?

A

Cheap, safe in low dose

Good for neuropathic pain

Also treats depression, poor sleep

45
Q

what are the dosadvantages of amitriptyline

A

Anti-cholinergic side effects (e.g. glaucoma, urinary retention)

Long term use might be linked with cognitive decline and dementia

46
Q

what are anticonvulsant drugs and what are some examples of them?

A
  • Examples - Carbamazepine, Sodium valproate, Gabapentin (pretty addictive)
  • Also called membrane stabilisers
  • Reduce abnormal firing of nerves (which we see in neuropathic pain)
47
Q

what type of pain are anticonvulsant drugs good for?

A

•Good for neuropathic pain

48
Q

Choose Best Route of Delivery for Individual Patient - what should be thought about and considered?

A
  • Patient might be NBM (nill by mouth so nothing to eat or drink)
  • If prescribing IM or S/C consider how much the patient might require (in a 24 hour period) and if that is acceptable as dont want to many injections. S/C cannula more tolerable
  • Oral route preferred where possible
49
Q

what are the different delivery routes?

A
  • Oral
  • Rectal
  • Sublingual
  • Subcutaneous
  • Transdermal
  • Intramuscular
  • Intravenous – boluses, possibly patient controlled systems or nurse administered
  • Intrathecal/Epidural
50
Q

what are the delivery routes for local anaesthetic?

A
  • Epidural (+/- Opiates – can be added to enhance pain management)
  • Intrathecal (+/- Opiates)
  • Wound Catheters
  • Nerve Plexus Catheters
  • Local Infiltration of wounds (at end of procedure to reduce post op pain)
  • Lidocaine patches for some neuropathic pain conditions
51
Q

what are the different ways to do an assessment of pain?

A
  • Verbal Rating Score
  • Numerical Rating Score
  • Visual Analogue Scale
  • Smiling faces
  • Abbey Pain Scale (for confused patients)
  • Functional assessments
52
Q

whata re the two different categories of treatment?

A
  • Non Drug Treatment (can be useful, may be things like positioning)
  • Drug Treatment
53
Q

what are some physical non-drug treatments?

A

Rest, ice, elevation

Surgery (may treat pain the the long run e.g. reduce fracture then pain reduced after that)

Acupuncture, massage, physiotherapy

54
Q

what is some psychological non-drug treatments?

A

Explanation (of pain and its normal and will get better)

Reassurance (say it will be better over the next couple days)

Counselling (need extra help coping with pain and their circumstances)

55
Q

what nociceptive pain and neuropathic pain, how do we decide on what drug treatments?

A
  • Acute Pain Use WHO Pain Ladder
  • Neuropathic Pain: use alternative analgesics and/or psychological and non drug treatments. Not responsive to WHO pain Ladder drugs

(Opioids not recommended for neuropathic pain)

56
Q

whata re the steps of the WHO Pain Ladder?

A
57
Q

Link Pain Assessment to prescribing for acute nociceptive pain:

what do you do for mild, moderate and severe pain?

A
  • Mild Pain: Start at Bottom of Pain Ladder
  • Moderate Pain: Bottom of Pain Ladder plus Middle Rung
  • Severe: Bottom of Pain Ladder plus Top of Ladder. Miss out the middle
  • It is okay to start at the top of the ladder for severe/ unbearable pain!!!!
58
Q

as pain resolves, what should you do?

A
  • Move from top to middle of WHO ladder
  • Continue Bottom Rung drugs at all times
  • Lastly stop NSAIDs first, then Paracetamol as more adverse effects with NSAIDs
  • Clear instructions must be given regarding reduction of all opioids (strong ones like morphine)
59
Q

The ___ Approach to Pain Management

A

RAT

60
Q

what is the RAT approach?

A

•Recognize (may be easy or the patient may not be able to express pain)

•Assess

  • Severity?
  • Type?
  • Other factors?

•Treat

  • Non-drug treatments
  • Drug treatments
61
Q

how do you recognize pain?

A

•Does the patient have pain?

  • Ask
  • Look (frowning, moving easily, sweating?)

•Do other people know the patient has pain?

  • Other health workers
  • Patient’s family
62
Q

how do you find out the severity?

A

•What is the pain score?

  • At rest
  • With movement

•How is the pain affecting the patient?

  • Can the patient move, cough?
  • Can the patient work?

(Want to know the functional effect of pain)

63
Q

how do you determine the pain type?

A

Nociceptive or neuropathic?

-Look for neuropathic features:

  • Burning or shooting pain
  • Phantom limb pain
  • Other features (pins and needles, numbness)

See if it is nociceptive pain so you can use the WHO pain ladder

64
Q

Any other factors that mean they are more susceptible to pain or harder to treat?

Anything that makes their pain experience worse?

A
  • Physical factors (other illnesses)
  • Psychological and social factors:
  • Anger, anxiety, depression
  • Lack of social support
  • Previous drug use/addictive personality
65
Q

what are osme non-drug treatments?

A
  • RIE - Rest, ice, elevation of injuries
  • Nursing care
  • Surgery, acupuncture, massage, TENS etc
  • Psychological
  • Explanation and reassurance
  • Input from social worker/pastor
66
Q

what drug treatments are avalible for nociceptive pain (WHO pain ladder)?

A

Mild - Paracetamol (± NSAIDs)

Moderate - Paracetamol (± NSAIDs) + codeine/ alternative

Severe - Paracetamol (± NSAIDs) + morphine

67
Q

WHo pain ladder is often not applicable to neuropathic pain, what treatment can be used instead?

A

Traditional drugs may not be as useful

Use other drugs early:

  • Amitriptylline
  • Gabapentin
  • Duloxetine

Don’t forget non-drug treatments (important for this type of patient group)

68
Q

after RAT, what should be done?

A

•Reassess the patient

  • Is your treatment working?
  • Are other treatments needed?
69
Q

RAT approach summary:

A

•Recognize

•Assess

  • Severity?
  • Type?
  • Other factors?

•Treat

  • Non-drug treatments
  • Drug treatments