2. Definition
“Pain is whatever the experiencing
person says it is, existing where
he/she says it does”
McCaffery (1980)

3. Physiology of pain
In its simplest form, the pain circuit in the body
can be described as follows
• pain stimulates pain receptors, and this stimulus
is transferred via specialised nerves to the spinal
cord and from there to the brain.
• The pain stimulus is processed in the brain,
which then sends an impulse down the spinal
cord and via appropriate nerves which command
the body to react, for instance by withdrawing
the hand from a very hot object.

4. Pain Receptors
• Pain receptors are present everywhere in the
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•
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body;
Pain receptors are free nerve endings.
There are three types of pain receptor stimuli:
mechanical, thermal and chemical.
A mechanical stimulus e.g. high pressure or
stretching; thermal pain stimulus would be
extreme heat or cold.
Chemical pain receptors can be stimulated by
chemicals from within and outside the body.

5. Pain nerve fibres
• Pain stimulus is transmitted from the receptors
•
•
through peripheral nerves to the spinal cord and
from there to the brain.
This happens via two different types of nerve
fibre: “fast pain” and “slow pain” fibres
Fast pain is well localised, sharp and “cutting”
and do not radiate.

6. Fast Pain Nerve Fibres
• They are thick nerve fibres called A-delta fibres.
•
•
Because of their relative thickness.
Pain stimulus are transferred very fast at a
speed of 2-5s/m
This allows the body to withdraw immediately
from the painful and harmful stimulus in order to
avoid further damage

7. Slow Pain Nerve Fibre
• They are thin nerve fibres called c nerve
fibres.
• Pain impulse are transmitted slowly to the
brain, at a speed of less than 2 m/s.
• The body responds by holding the
affected part immobile (guarding, spasm
or rigidity), so that healing can take place.

8. Pain transmission in the spinal cord and
the brain
• The peripheral nerves carry the pain impulse to
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•
•
the spinal cord.
In the spinal cord, fast pain and slow pain are
carried up to the brain via different pathways
The impulse of the fast pain goes to the cortex,
allowing for the relatively precise localisation of
the pain stimulus.
The impulse from slow pain is distributed
diffusely in the brain, with each area eliciting a
different response

9. Characteristics of fast pain and slow
pain
Slow Pain
• Transmitted by very thin nerve
fibres
• Poorly localised
• All internal organs (except the
brain)
• Body wants to be immobile to
allow healing (guarding,
spasm, rigidity)
• Pain often radiates, or is
referred
07/11/2013
Fast Pain
• Transmitted by relatively
thicker (and therefore faster
conducting) nerve fibres
• Well localised
• Mainly skin, mouth, anus
• Immediate withdrawal of
stimulation to avoid further
damage
• Pain does not radiate
• Little relief from opioids
Reviewed by Prof CL Odendal, senior specialist at the
department of anaesthesiology at the University of the
Free State, April 2010.

10. Pain in the Elderly
• Effects of aging on pain sensation, perception, and
•
behaviour are not well established
Compared with younger adults, elderly persons rely more on
slow/second pain (C fibre) than on fast/ first pain (A fibre).
• Another well-documented finding in the elderly is a slower
response time to pain
• No evidence exists that pain intensity lessens with age

11. • Altered reactions to painful events may be due to loss of
communications skills, cognitive abilities, or the failure of
basic reflexes due to aging
• Additionally, pain in the elderly may be manifested as
something other than pain, such as delirium

12. Pain in Children
• Children and young people have a right to appropriate
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•
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prevention, assessment and control of their pain
Historically, pain has been underestimated and under
treated in children and particularly babies.
Evidence shows that pain is inadequately dealt with for
children, requiring better prevention, assessment and
treatment.
In order to treat children's pain effectively, a thorough
pain assessment is necessary; a number of guides are
available to do this

13. • British association for Emergency Medicine
Clinical Effectiveness committee: Guideline for the
management of pain in children

14. How do we assess pain?
• Self report
• Use pain rating tools
• Non-verbal signs
• Assess on movement
• Document

15. Pain Assessment
Severe Pain (3)
“Pain is whatever the patient says it is”
„Hurts as much
as I can imagine
Moderate Pain (2)
„Hurts more‟
Mild Pain (1)
„Hurts just a little bit‟
No Pain (0)
„Happy because I
don‟t hurt at all‟
Always assess on movement

16. Other Pain tools
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Intensity scores - VAS, Categorical
Pain relief scales
Cognitively impaired
Paediatric
Critical care
Chronic Pain
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McGill Questionnaire
Quality of Life Questionnaire
Brief Pain Inventory
Pain Self Efficacy Questionnaire

17. What do we assess?
• Location
• Duration
• Type
• Intensity

18. What needs to be considered when
assessing pain?
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Subjective
Age
Communication
Psychiatric factors
Cognitively impaired
Culture
Knowledge of pain
treatments
• Expectations of pain
•
treatments
Language barriers

19. Barriers to pain assessment in the older
person
• Failure to recognise
• Failure to assess
• Assume stoicism
• Patients & carers expectations of pain in
ageing
• May use different words e.g. discomfort,
ache, soreness
• Time consuming

20. Inadequate pain management can
cause:
• physiological effects (increased HR, BP, delayed
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gastric emptying, increased adrenaline
production)
post-operative complications (respiratory
infection, VTE, PE)
delayed discharge
mobilisation difficulties
restlessness, irritability, aggression
raised levels of anxiety
sleep disturbances
distress and suffering
(Sjostrom et al 2000, Macintyre & Ready 2002, Carr et al 2005)

21. Pain Management
and the role of
Psychology

22. Acute Vs Chronic Pain

Acute Pain
– Short Term
– Less than 3 months
– Natural Healing Occurs

Chronic Pain
–
–
–
–
–
Long Lasting
Longer than 3 months
Natural Healing occurs
but huge IMPACT
Pain as a result of
Central NS changeslocal, spinal cord,
brain

23. Why do people react so differently to Pain?
Pain
Beliefs About
Pain
Leventhal‟s Common Sense Model
Action Taken /
Coping

24. Chronic Pain and
Psychological Distress
How does psychological distress affect
pain experience and management?
Chronic Pain
?
Anxiety &
Depression

25. The BioPsychoSocial Model

26. Psychological Interventions

Cognitive Behavioural Therapy shown to
be effective
– Has impact on biopsychosocial variables

However, psychological interventions for
chronic pain most effective when
incorporate other treatment components
– e.g. physiotherapy, education
– Pain Management Programmes

27. Impact of Chronic Pain
Reduction in activity
Failed Treatments
eg physio, med
Pain
Loss of Job,
Financial Stress
Being Blamed/
Faking it
Relationships
Physical
Deconditioning
Depression
Hopelessness,
Helplessness
Anxiety
Fear re Future
Excess
Suffering
Frustration
Anger
Loss of Independence
Boom and Bust

28. Pain Management Aims

NOT cure or pain reduction

Change the person‟s relationship with pain
– Reduce disability and distress
– Manage increases in pain (flare-ups)
– Develop confidence in ability to carry out activities
despite pain
– Reduce unhelpful encounters with public and private
health systems
– Self-Management

29. Aims of Pain Management
Improve Fitness
•Education re Pain
Model
•Exercising
•Flare-up Planning
Pain
•Goal Setting &Practice
•Pacing
•Identifying unhelpful
thoughts
•Relaxation
•Communication
Improve daily
functioning
Reduce anxiety/
depression
Reduce
Increase confidence Distress
Reduce dependence
Reduce incidence of
Flare-Ups

30. MDT
Consultants, physios, psychologists,
nurses
 Pain Management Programmes

– Good evidence base, improve functioning
 NICE guidance 88, May 2009
– Outpatient Programmes
 PMP @ Whittington, COPE @ UCH
– Inpatient Programmes
 INPUT Pain Management Unit @ St Thomas‟
 Bath Pain Management Unit

31. References

Sharp & Keefe (2006). Psychiatry in Chronic Pain: A review and Update.
Focus, American Psychiatric Association.

Turk & Okifuji (2002). Psychological factors in chronic pain: Evolution and
revolution. Journal of Consulting and Clinical Psychology.

Vlaeyen & Linton, (2006). Are we „fear avoidant‟. Pain.

Vlaeyen & Morley (2005). Cognitive-Behavioural Treatments for Chronic
Pain: What works for whom? Clinical Journal of Pain.

Morley, Eccleston & Williams (1999). Systematic review and meta-analysis
of randomized controlled trials of cognitive behaviour therapy and behaviour
therapy for chronic pain in adults, excluding headache. Pain.

Nicholas M, Molloy A, Tonkin I and Beeston L (2000) Manage your Pain
ABC Books, Sydney

Nice, Nice Guideline 88 (2009) – Early management of persistent nonspecific low back pain, http://www.nice.org.uk/CG88