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PAIN
KATE BLACK
KATE BRAZZALE
LISA MOLONY
PAIN
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Aetiology
Disorder/Disease
Clinical Manifestations
Pathophysiology
Diagnosis
Pharmacological Management
Non-Pharmacological Management
Complications
Implications for Nursing Practice
WHAT IS PAIN?
According to the International Association for the Society of
Pain,
Pain is “an unpleasant sensory and emotional experience
associated with actual or potential tissue damage, or
described in terms of such damage”.
http:/www.iasppain.orgContentNavigationMenuGeneralResourceLi
nks/PainDefinitions/default.htm
AETIOLOGY: WHAT CAUSES PAIN?
• “Pain can be due to a wide variety of
diseases, disorders and conditions
that range from a mild injury to a
debilitating disease”.
http://www.localhealth.com/article/pain
ACUTE PAIN
“The terms acute and chronic refer exclusively to the time course of
the pain, irrespective of aetiology” (Craft, Gordon, and Tiziani, 2011, p.144).
Acute Pain:
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Usually lasts less than 3 months
Sudden onset
Usually well defined
Predicable ending (healing)
Can lead to chronic pain if left untreated
• Examples: cut to the finger, broken bone
CHRONIC PAIN
Chronic Pain:
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Persistent or recurring pain
Continues for more than 3 months
May last for months or even years
Can be difficult to diagnose and treat
Primary goal is not total pain relief but reducing pain relief
• Examples include: arthritis and back pain
CATEGORIES OF PAIN
Another way to categorise pain is on the basis of
origin:
• Nociceptive
• Neuropathic
• Psychogenic
NOCICEPTIVE PAIN
Nociceptive pain is directly related to tissue damage and can be
either external (somatic) or internal (visceral)
External / Somatic
• Most common type of pain
• Can be superficial -in the skin but may extend to the underlying
tissues.
• Usually described as: sharp, shooting, throbbing, burning, stinging
• well defined area
• Usually lasts from a few seconds to a few days
• Examples include: paper cut, sprained ankle
NOCICEPTIVE PAIN
Internal / Visceral (Deep)
Less common and usually more severe
Originates in the walls of visceral organs
Poorly defined area
Described as: deep, aching, pressing or aching
Usually lasts a few days to weeks
Virtually a symptom of all diseases at some point during disease
progression.
• Often associated with feeling sick
• Examples include: Major surgery, labour pain, irritable bowel.
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NEUROPATHIC PAIN
• Injury or disease of the central nervous system
rather than the peripheral tissue.
• May be due to nerve compression,
inflammation or trauma
• Usually lasts between a few months to many
years.
• Difficult to treat due to the lack of knowledge
of the underlying cause.
• Often associated with paraesthesia,
hyperalgesia and allodynia
• Burning, shooting or pins and needles (not
sharp like nociceptive).
PSYCHOGENIC PAIN
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Psychological, psychiatric or psychosocial at the primary causes
Severe and persistent pain
Appears to have no underlying pathology.
Less common now due to medical technology
Pain experienced (Headaches, abdominal pain, back pain) is
indistinguishable from that experienced by people with identifiable
injuries or diseases.
• This kind of pain can be very
frustrating to sufferers and can
interfere with their ability to function
normally.
CLINICAL MANIFESTATIONS
“No two people are likely to experience the same level of pain for a given
painful stimulus” (Craft et al., 2011, p.150).
Pain Tolerance:
The maximum level of pain that a person is able
to tolerate without seeking avoidance of the
pain or relief
What affects Pain Tolerance?
• Fatigue, anger, boredom, apprehension,
sleep deprivation. Alcohol consumption,
medication, hypnosis, warmth, distracting
activities and strong beliefs or faiths.
CLINICAL MANIFESTATIONS
Pain tolerance is influenced by a number of factors
including;
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Age
Cultural perceptions
Expectations
Gender
Physical and mental health
CLINICAL MANIFESTATIONS
Age:
• Different reaction to pain
• Understanding of pain
Gender:
• “Females display greater sensitivity to pain than males do. There are
differences in the way women cope with pain, report pain and
respond to pain” (Crisp & Taylor, 2009, p.1096).
Physical & Mental Health
• Physical mobility
• Depression, difficulty coping, fatigue.
CULTURAL VARIATIONS
Cultures vary in the meaning of pain, how if it expressed
and how it is treated:
• Meaning
• Expression
• Treatment
PAIN THRESHOLD
• Pain Threshold is the lowest point at which pain can be felt
• Entirely subjective
• May vary from person to person but changes little in the same
individual over time.
LOCATION
It is important record a patients pain location to be able to
monitor any changes.
Pain can feel like it is
coming from one part
of the body but in fact it
is another, this type of
pain is called referred
pain.
SIGNS AND SYMPTOMS:
Signs:
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Change in temperature
Blood pressure
Respiratory rate
Heart rate
Short of breath
Sweating
Pallor
Dilated pupils
Swelling
Symptoms:
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Fatigue
Feeling sick
Weakness
Numbness
Tenderness
Change in behaviour
Unable to sleep
PATHOPHYSIOLOGY
• Pain is not a disorder or disease.
• A consequential reaction by the body to
noxious stimuli.
• Injury
• Disease
• Pain incorporates
• Cognition
• Emotion
• Behaviour
• Simple pathway to the brain;
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Transduction
Transmission
Perception
Modulation
PATHOPHYSIOLOGY
• Transduction
• Process by which afferent nerve endings participate in translating
noxious mechanical, chemical or thermal impulses into
nociceptive impulses.
• Strong physical stimuli and disease processes cause chemical
release.
• Once activated the chemicals bind to specific receptors.
• chemicals such as bradykinin, cholecystokinin and prostaglandins,
activate or sensitize nearby nociceptors
• Lead to the generation of Action Potentials (AP)
TRANSDUCTION
PATHOPHYSIOLOGY
• Transmission
• 1st Order Sensory Neurons
• Located in the dorsal root ganglia in the posterior of the spinal
cord.
• AP’s are conducted to the CNS primarily via two types of
primary afferent neurons
• A delta Fibres "Epricritic Pain"
• C Fibres "Protopathic Pain"
• 2nd Order Sensory Neurons
• The impulse crosses the spinal cord and ascends to the
thalamus and branches to the brainstem nuclei via central
transmission.
• Messages cross the cord and ascend to the thalamus via the
Spinothalamic pathway, heading to the somatosensory cortex,
the insula, frontal lobes and limbic system.
A-DELTA AND C FIBRES
Nerve fibre
Aδ
C
Appearance
Type of Pain
Epicritic
Protopathic
Information
carried
•Sharp pain
(‘fast pain’)
•Temperature
•Dull pain
(‘slow pain’)
•Temperature
•Itch
Diameter
1-5
(micrometres)
0.2-1.5
Speed of
signal
conduction
0.5-2.0 m/sec
5-35 m/sec
A delta Fibres
• "Epricritic Pain"
• Mechanical message
• Sharp, Fast pain
• Thin Myelinated fibres
increase speed of processing
C Fibres
• "Protopathic Pain"
• Mechanical and Thermal
Stimuli
• Slow, dull, long lasting pain
• Unmyelinated fibres, slower
response
PERIPHERAL TRANSMISSION
Peripheral transmission
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An electron micrograph showing
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large myelinated Aβ
small lightly myelinated Aδ fibres
unmyelinated fibers C Fibres.
SYNAPTIC TRANSMISSION
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Synaptic transmission
• Action potential synapse at
the dorsal horn of the spinal
cord
• Neuroactive excitatory and
inhibitory neurotransmitters
are released
• Lead to generation of
action potentials and
central transmission of pain
signals to higher centres.
PATHOPHYSIOLOGY
• Perception
• The process by which a noxious event is recognized as pain by a conscious
person.
• Multiple areas of the brain are involved. There is no one location where
perception occurs, although major defining components of pain are
attributed to processes that take place in specific areas of the brain.
• For example, the sensory-discriminative component is the result of activity
in the somatosensory and the insular cortex, which allows the person to
identify the type, intensity and bodily location of the noxious event.
• The affective-emotional response to the noxious stimulus is mediated by
the limbic system. Pain has an inseparable affective-emotional component
that defines the response and associated behavior resulting from the
initiating noxious event or stimulus.
• 3rd Order Sensory Neurons
• To the higher brain centres of Limbic system
• Frontal cortex, primary sensory cortex of the post central gyrus of
PATHOPHYSIOLOGY
• Modulation
• Descending input from the brainstem influences central nociceptive
transmission in the spinal cord.
• Specific brainstem nuclei send projections to the dorsal horn of the spinal
cord and when activated by ascending nociceptive impulses and other
influences from the brain result in descending modulation.
• Though not completely understood, modulation results in descending
inhibition of nociception through the release of neurotransmitters such as
serotonin, norepinephrine and endogenous opioids.
• Modulatory processes can also increase descending facilitation of
nociception and consequently pain. Psychological factors such as fear
and anxiety exert facilitatory influences through these modulatory systems.
DIAGNOSIS
• Diagnosis of Pain
is complicated.
• To diagnose pain,
Nurses rely on
• Objective Data.
• Visual signs.
• Subjective Data.
• Patients
descriptions.
• Characteristics of
Pain.
DIAGNOSIS
• Characteristics of Pain
• OPQRST Mnemonic
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Onset
Provocation
Quality
Region/Radiation
Severity
Time
DIAGNOSIS
1. Onset
• What was the patient doing at the time?
• What precipitated the pain?
• Is there any history of this pain in the patient?
2. Provocation
• Aggravating Factors:
• What causes the Pain to increase?
• Alleviating Factors:
• What makes it better or worse?
DIAGNOSIS
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Quality
• Get the patient to describe their pain to you in specific terms.
• What does it feel like?
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Region/Radiation
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Where is the pain?
Where does the pain radiate?
Is it in one place?
Does it go anywhere else?
Did it start elsewhere and now localised to a different spot?
DIAGNOSIS
5.
Severity
• Pain Rating
• On a scale of 1 to 10, 10 being the worst pain you have experienced,
what number would you assign to your discomfort?
• Does their pain change with medication?
• Wong-Baker Faces Pain Rating Scale.
• Used for
• Children
• People whose first language is not English.
DIAGNOSIS
DIAGNOSIS
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Time
• When did the pain start?
• How long has the patient has this pain?
• Are there any Associated Phenomena?
• Factors consistent with pain e.g. Anxiety
• Physiological responses
• Sympathetic stimulation
• Parasympathetic stimulation
• Vital signs, skin colour, perspiration, pupil size, nausea, muscle tension,
anxiety
• Behavioural Responses
• Posture, gross motor activities
SPINAL NERVES
• 3 Categories
• Dermatomes
• Connective Tissue and Dermis
• Myotome
• Skeletal Muscle
• Sclerotome
• Vertebrae
• Dermatomes in relation to pain
• An area of skin in which sensory nerves derive from a single
spinal nerve root.
DERMATOMES
• Spinal Cord Dermatomatic Relationships
• Trigeminal Nerves
• V1Ophthalmic Division – Eye
• V2 Maxillary Division – Top of Jaw
• V3 Mandibular Division – Bottom of Jaw
• Cervical (C-2 - C-7)
• fingers, neck, funny bone, and the scalp.
• Thoracic (T-1 - T-12)
• nipples, chest, belly button area, pubic bone, and lower
sternum.
• Lumbar (L-1 - L-5)
• hips, the front of the legs, the shins, knee caps, and most of the
feet.
• Sacral (S-1 - S-5)
• genitals, buttocks, back of the legs, and calves
DERMATOMES
DIAGNOSTIC TESTS
Tests to verify pain.
•Ultrasound Imaging
• High frequency sound waves to develop an
image of the affected area.
•CT/CAT scan
• Computed Tomography or Computed Axial
Tomography
• X-rays to produce an image of a crosssection of the body.
•MRI Scan
• Large magnet, radio waves and a computer
produces detailed images of the body.
DIAGNOSTIC - TESTS
• Discography/Myelograms
• A contrast dye is injected into the spinal disk
to enhance the X-Ray.
• EMG (Electromyography)
• Evaluate the activity of the muscles.
• Bone Scans
• Diagnose and monitor
infection and fracture of
the bone
DIAGNOSIS
• Psychological Assessment
• Pain Questionnaires
• Determine Psychological Involvement.
• Brain functions governing behaviour and decision making,
including expectation, attention and learning.
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Fear
Anxiety
Depression
Coping
• Psychosocial involvement.
• Plays a large role in pain perception.
• Age, Sex, Culture, previous experiences.
GENERAL PRINCIPLES
OF PAIN MANAGEMENT
• Treat the cause of pain where possible, not just the
symptom
• Make accurate diagnosis and assessment of pain extent
and type to ensure appropriate analgesic prescription
• Keep the patient pain free
• Dose at regular specified intervals, particularly for
chronic pain (rather than PRN)
• Avoid the chronic pain stress cycle and 'sick role‘
• Prevent adverse effects of opioids
• Develop a patient management plan
• Follow the WHO analgesia ladder
PHARMACOLOGICAL MANAGEMENT
• WHO has developed a
three-step ladder for pain
relief
• If pain occurs, the use of
oral of drugs should be
administered in the
following order:
1. non-opioids
2. mild opioids
3. strong opioids
Image: World Health Organization
http://www.who.int/cancer/palliative/painladder/en/
PHARMACOLOGICAL MANAGEMENT
• Involves the management of pain through analgesics
• Analgesic: a compound that relieves pain by altering
perception of nociceptive stimuli without producing
anaesthesia or loss of consciousness
• Three types of analgesics:
1. Opioids (narcotic) analgesics
2. Non-opioid analgesics (NSAIDs)
3. Adjuvants (DISCUSS HERE WHAT ADJUVANTS ARE OR
ADD IN A SLIDE LATER)
PHARMACOLOGICAL MANAGEMENT
• Routes of administration:
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Oral
Intravenously
Continuous infusion (via SC or IV routes)
Rectally
Transdermal administration
Inhalation
OPIOIDS
• Generally prescribed for moderate – severe pain
• Act on CNS by binding with opiate receptors to
modify perception and reaction to pain
• The most commonly used opioid is morphine
OPIOIDS
• Add table of commonly used opioids,
advantages/disadvantages
OPIOIDS
• Adverse drug reactions may include:
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respiratory depression
excessive sedation
constipation
nausea
vomiting
tolerance
dependence
dysphoria (a mood of general dissatisfaction, restlessness,
anxiety)
NSAIDS
• Non-steroidal anti-inflammatory drugs
• Used to treat mild – moderate pain
• Work by acting on peripheral nerve receptors to
reduce transmission and reception of pain stimuli
• Common NSAIDs include:
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Paracetamol
Aspirin
Ibuprofen
Naxopren (arthritis)
NSAIDS
• Adverse reactions may include:
• gastrointestinal tract disorders (dyspepsia, nausea and
vomiting, diarrhoea/constipation)
• renal damage
• asthma attacks
• skin reactions
• sodium retention and consequent heart failure and
hypertension
• Large overdoses of paracetamol can cause fatal
acute liver damage if not promptly treated.
NSAIDS
Aspirin vs Paracetamol
• Aspirin is readily available OTC. It can be used in stroke
prevention due to its anti-platelet qualities.
• In normal doses, paracetamol is a safer OTC analgesic than
aspirin for the following reasons:
• adverse effects and allergic reactions are rare with therapeutic doses
• there is low risk of gastic upset, renal impairment or peptic ulceration
compared with aspirin
• plasma protein binding is negligible (no risk of displacement causing
drug interactions)
• few serious adverse drug interactions
• may be used by children
• safe to use during pregnancy and lactation
INCLUDE SLIDE ON ADJUVANTS?
PHARMACOLOGICAL MANAGEMENT
Other drugs useful for analgesic effects
• GABA analogues
• Capsaicin
• Local anasthetics
• General anasthetics
• Ethanol or phenol
• Cannabinoids
• Specific anti-migraine drugs
• Herbal remedies (e.g. cloves, feverfew, kava kava, St
John's wort, ginger, ginseng)
NON-PHARMACOLOGICAL
MANAGEMENT
• Definition?
• Useful for patients who:
find such interventions appealing
express anxiety and/or fear
may benefit from avoiding or reducing drug therapy
are likely to need to cope with a prolonged interval of postoperative pain
• have incomplete pain relief after use of pharmacological
interventions
• are able to use the intervention without assistance (TENS,
heat packs)
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NON-PHARMACOLOGICAL
MANAGEMENT
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RICE (rest, ice, compression, elevation)
Physiotherapy
Counter-irritants
TENS
Acupuncture
Psychotherapeutic methods
Surgery
Community support groups
Complementary and alternative medicine aromatherapy, herbal medicines, spinal manipulation
HOT AND COLD THERAPY
• From: Clinical Psychomotor Skills pg 153
PSYCHOTHERAPEUTIC
• Psychotherapeutic methods - hypnosis, behaviour
modification, biofeedback, techniques,
assertiveness training, art and music therapy, the
placebo effect
• More info on this – find some journals
• Heaps of info in Crisp & Taylor
TENS MACHINE
TENS MACHINE
TENS MACHINE
COMPLICATIONS
COMPLICATIONS
• Acute –
• Cardiovascular
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• Respiratory
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• Genitourinary/Gastrointestinal
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• Musculoskeletal
• Pressure Ulcers whilst in Hospital if unable to move from the bed
• Cognitive/Psychological
• Possible Fear or Anxiety surrounding injury and healing process
COMPLICATIONS
• Chronic –
• Cardiovascular
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• Respiratory
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• Genitourinary/Gastrointestinal
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• Musculoskeletal
• Pressure Ulcers whilst in Hospital if unable to move from the bed
• Cognitive/Psychological
• Possible Fear or Anxiety surrounding injury and healing process
IMPLICATIONS FOR
NURSING PRACTICE
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Nurses role in pain management
Administer pain-relieving interventions
Assess the effectiveness of these interventions
Monitor for adverse effects
Be an advocate for the patient when the
prescribed intervention is ineffective in relieving
pain
Serve as an educator to the
patient and family
IMPLICATIONS FOR
NURSING PRACTICE
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Establishing a nurse-patient relationship
Positive nurse-patient relationships and teaching
are KEY
Communication and patient cooperation
Believe and acknowledge that the patient is in pain
– reduces anxiety
‘I know you have pain' often eases the patients
mind
Education is important
Provide information
IMPLICATIONS FOR
NURSING PRACTICE
Identifying goals
• May include decrease in the intensity, duration,
frequency, or a reduction in the side effects of pain
• Consider:
• the severity of the pain
• the anticipated harmful effects of pain
• Anticipated duration of pain
• ‘No pain’ may be an unrealistic goal.
• Will goal be achieved by pharmacological or nonpharmacological treatments or both?
IMPLICATIONS FOR
NURSING PRACTICE
Providing physical care
• Ensure the patient is as comfortable as possible
• Ensure that physical and self-care needs have been met
and that patient feels refreshed. This might include:
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Fresh gown
Change of bed linen
Teeth are brushed
Hair is combed
• Gives the nurse the opportunity to perform a complete
assessment
• Appropriate and gentle physical touch during care may
also be reassuring and comforting
• Assess skin integrity (patches, IV lines)
IMPLICATIONS FOR
NURSING PRACTICE
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Managing anxiety related to pain
A patient who anticipates pain may become
increasingly anxious.
Patients who are more anxious are likely to be less
tolerant.
Educate the patient on pain and pain
management
Gives a sense of control
Good nurse-patient relationship is crucial
IMPLICATIONS FOR
NURSING PRACTICE
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Interventions - Who else may be involved?
Oncology nurse
Physiotherapist
Occupational therapists
The family or caregiver
People in the community: visiting nurses,
pharmacists, general practitioner, palliative care
nurses
REFERENCES
REFERENCES