Classification of pain Flashcards
Three main ways to classify pain
Duration- acute/chronic
Cause-cancer vs non cancer
Mechanism- nociceptive, inflammatory, neuropathic, (Dys)functional
Characteristics of acute pain
- Pain of recent onset and probably limited duration
- Obvious tissue injury
- Varying severity
- Intensity related to extent of injury
- Predictable time course
- Treatments usually successful
Characteristics of chronic pain
Pain lasting for more than 3 months
Pain lasting after normal healing
Sometimes non identifiable
May be no obvious pathologic process
Intensity unrelated to tissue injury
Unpredictable time course
Difficult to treat
What is cancer pain
Progressive
May be mixture of acute and chronic
What is non-cancer rpain
Many different causes
Chronic or acute
What is nociceptive pain
‘good’ pain because it is protective
Sensation associated with detection of potentially tissue-damaging noxious stimuli
What is inflammatory pain
Obvious tissue injury or illness
Associated with tissue damage and infiltration of immune cells and can promote relain by causing pain hypersensitivity until healing occurs
Protective function
What does inflammatory pain feel like
Sharp and/or dull
Aching
throbbing
Well localised
What is pathological pain
Maladaptive
Results from abnormal functioning of nervous system
[disease states caused by damage to the nervous system- neuropathic pain
or by its abnormal function- dysfunctional pain]
What causes pathological pain
Disease states caused by damage to nervous system (neuropathic pain) or by its abnormal function (nocoplastic pain)
What is neuropathic pain caused by
Lesion or disease of the sensory nervous system
Tissue injury may not be obvious
Does not have protective function
What does neuropathic pain feel like
Burning, shooting, pins and needles, or numbness
Less well localised
Peripheral causes of neuropathic pain
Post surgery nerve injury plexus avulsion Amputatin Compression syndrome Infections (herpes, HIV) Trigeminal neuralgia Diabetes Toxins, e.g. ethanol Drugs inc chemo, metronidazole, hydralazine
Spinal causes of neuropathic pain
MS Spinal injury Tumour Arachnoiditis Syrinx
Brain causes of neuropathic pain
Stroke MS TUmour Epilepsy Syrinx
What is nociplastic pain and what’s the cause
Substantial pain but no noxious stimulus and no, or minimal, peripheral inflammatory pathology
NO neural damage (i.e. functional problem)
What conditions cause nocoplastic pain
Fibromyalgia, IBS, tension type headaches, temporomandibular joint disease, interstitial cystitis
What are acute non cancer pains usually
Usually nociceptive Occasionally neuropathic (e.g. sciatica)
What conditions are associated with chronic non cancer pain
Chronic back pain, arthritis. Cause may not be obvious
What type of pain may cause chronic non-cancer pain and what does this mean for treatment
Nociceptive and neuropathic
different treatments may be needed
What can the effect of long term pain be
Depressio Sleep disturbances Fatigue Impaired physical functioning Impaired concentration Time off work Less active
What may cause cancer pain
Bone metastases
Nerve compression
What type of pain is cancer pain usually
Often mixed nociceptive and neuropathic
Usually gets worse over time if untreated
What is not a good discriminator of pain
Duration of symptoms
Does neuropathic pain have a protective function
No
What is (dys)functional pain
Substantial pain but no noxious stimuli and no, or minimal, peripheral inflammatory pathology
No neuronal damage
Which conditions are associated with (dys)functional pain
Fibromyalgia IBS Tension headaches TMJ disease Interstitial cystitis
