Pain management Flashcards
Importance of pain management
•Surveys indicate that pain is experienced by
- 30-60% of cancer patient during active therapy
- More than 2/3 of those with advance disease.
•One of the most feared consequences of cancer for both patients and families.
•The single most common reason that patients visit physicians, clinical facilities and pharmacies.
Pain affects quality of life.
Pain is a comple experience influenced by:
A complex experience influenced by: – A person’s cultural background – Past experience – Anticipation of pain – Context in which pain occurs – Emotional and cognitive responses
Pain = “… an unpleasant sensory and emotional experience associated with actual or potential tissue damage”
A physiologic and psychological response that vary from person to person and from day to day.
Pain = “… an unpleasant sensory and emotional experience associated with actual or potential tissue damage”
A physiologic and psychological response that vary from person to person and from day to day.
Explain physiologic response of pain
Physiologic response –> normal response to a painful stimuli; plays an integral adaptive role as part of the body’s normal defence mechanisms, warning of contact with potentially damaging environmental insults and initiating behavioural and reflex avoidance strategies
Pain is the 5th vital sign
A protective mechanism that alerts injury and illness
- Pain prevents tissue damage and avoid further damage (numbness –> unknown injury –> more harm)
- Promote immobilization for healing
- Evidence of under-treatment
- A reflection on quality of care/life
explain psychological response of pain
Psychological response –> an unpleasant feeling (a suffering) of a psychological, nonphysical,
origin; mental a wide range of subjective experiences characterized as an awareness of negative changes in the self and in its functions accompanied by negative feelings
How pain affect quality of life
Physical
- Decreased functional capability
- Diminished strength, endurance
- Loss of appetite
- Poor or interrupted sleep
Psychological (many often) o Diminished leisure, enjoyment o Increased anxiety, fear o Depression o Difficulty concentrating o Loss of control
Social o Diminished social relationships o Decreased affection o Altered appearance o Increase caregiver burden
Spiritual
o Increase suffering
o Altered meaning
o Re-evaluation of religious beliefs
Pain classification
Chronic pain
• It is usually defined as pain which lasts beyond the ordinary duration of time that an insult or injury to the body needs to heal
•Commonly thought of as 4-6 weeks, although others have chosen 3 months as the dividing line between acute and chronic pain.
– Non-malignant
• Headache
• Migraine
• Chronic arthritis
– Malignant
• Cancer pain
Acute pain
Sudden and have tissue damage
Types of pain
Types of pain
Nociceptive pain
It is the perception of nociceptive input described in terms of tissue damage – “sensation” of pain.
2 subtypes: Somatic and visceral pain
Neuropathic pain
Caused by injury to nerves
•Peripheral
•Central
Injury may be due to disease or its treatment (diabetes, infection, cancer, drugs, radiation)
- Often described as prolonged, severe, burning, lancinating, or squeezing, and is often associated with focal neurologic deficits.
- pain feeling : burning, tingling, shooting, electric/shocking pain
Somatic pain explain
type of nociceptive pain
• arises from damage to body tissues
• pathophysiology of somatic pain involves noxious mechanical, thermal, or chemical stimuli which trigger nociceptors, the specialized neural receptors for pain.
– signals are carried by
• small myelinated A-delta fibers (for mechanical and thermal stimuli) and
• C fibers (for all three stimulus types)
to the dorsal horn of the spinal cord.
- Pain is tender and localized to the site of injury, is constant and sometimes throbbing or aching
2 types:
Cutaneous –> skin
Deep –> Muscle, tendon, ligament, blood vessel.
pain feeling: aching, throbbing, stabing, pressure
Visceral pain explain
type of nociceptive pain
- arising from the viscera mediated by stretch receptors
- visceral pain is poorly localized and often referred to a distant cutaneous site which may be tender
- described as deep, dull, and cramping (eg, appendicitis, cholecystitis)
- Disease mainly in peritoneal cavity and when viscera stretches it activate nociceptive receptor.
pain feeling: gnawing, crampping , aching , sharp pain
Principle of Pain Assessment
- Believe the patient’s complain of pain
- May not appear to “look like they are in pain”, but appear distressed
- Autonomic signs associated with acute pain (increase RR, HR, BP, diaphoresis)
1) Believe the patient’s report of pain
2) Use open ended questions
3) Take history for each pain
4) Look out for psychological distress
Tell me about the pain:
• Site: Where is it?
• Onset: When did it start? How did it start?
• Character: How does it feel ?
• Radiation : Does it run anywhere else?
• Associations : Any other symptoms?
• Time course: How long have you had it?
• Exacerbating/ relieving factors: What makes it worse?
What makes it better?
• Severity: How bad is it?
Goal of assessment
•Characterize and Quantify the pain •Identify pain syndrome - Acute/chronic/breakthrough - Cancer/Non-cancer related •Infer pathophysiology - Nociceptive pain/Neuropathic pain •Evaluate physical and psychosocial comorbidities •Assess degree and nature of disability •Develop a therapeutic strategy
Characterising Pain Quality
Characterising Pain Quality
•Somatic: pain in skin, muscle, bone
- Described as aching, stabbing, throbbing
•Visceral: pain in organs or viscera
- • Gnawing, cramping, aching, dull
•Neuropathic: pain caused by nerve damage
- • Sharp, tingling, burning, shooting
Approach to pain management
Principle 1 : Treat the underlying cause where possible
Examples:
•Orthopaedic fixation of fractures
•Chemotherapy/radiotherapy to shrink the tumour
•Bowel clearance for constipation
•Reduce raised intracranial pressure
•Nitrates/ angioplasty for CAD
•Arterial bypass for PVD
•Joint replacement for severe OA knee/ hip
Principle 2: Ask what is the Pain Mechanism(s) behind the pain Examples: • Nociceptive Pain : tissue injury • Neuropathic Pain : nerve injury • Mixed
Principle 3: pharmacological tx using pain ladder
Mild pain (1-3)
•Patient not on analgesics:
Begin with acetaminophen or NSAIDs/Coxib (non‐opioid medications); aspirin generally avoided due to irreversible antiplatelet effects.
•Patient on analgesics (still not controlled) :
Consider titrating short‐acting opioid and beginning bowel regimen
Moderate pain (4-6) •Begin with weak opioid agonists (codeine, tramadol DMP, tapentadol) / - stronger opioid but lower dose (if still not useful)
Severe pain (7-10 ) •Begin with strong opioid agonist (morphine, fentanyl, oxycodone, hydromorphone. methadone, nerve block, spinal analgesia)
WHO treatment guides for cancer pain – 5 simple recommendations
WHO treatment guides for cancer pain – 5 simple recommendations
1) Oral administration of analgesics.
- The oral form of medication should be used whenever possible.
2) Analgesics should be given at regular intervals.
- To relieve pain adequately, it is necessary to respect the duration of the medication’s efficacy and to prescribe the dosage to be taken at definite intervals in accordance with the patient’s level of pain. The dosage of medication should be adjusted until the patient is comfortable. Goal is prevention of pain (takes less medication to prevent than to treat pain).
3) Dosing of pain medication should be adapted to the individual.
- There is no standardized dosage in the treatment of pain. Every patient will respond differently. The correct dosage is one that will allow adequate relief of pain.
4) Analgesics should be prescribed according to pain intensity as evaluated by a scale of intensity of pain.
- The pain-relief medications should be prescribed after clinical examination and adequate assessment of the pain. The prescription must be given according to the level of the patient’s pain and not according to the medical staff’s perception of the pain.
5) Analgesics should be prescribed with a constant concern for detail. The regularity of analgesic administration is crucial for the adequate treatment of pain.
- Once the distribution of medication over a day is established, it is ideal to provide a written personal program to the patient. In this way the patient, his family, and medical staff will all have the necessary information about when and how to administer the medications.
Match analgesic choice to severity of pain; titrate to response………….. give example
Match analgesic choice to severity of pain; titrate to response
- Rapid titration for severe pain.
- Slower titration for moderate pain.
- Even slower titration for mild pain.
