surgery and allied

2. Pain control and
postoperative analgesia
DR.NADIR MEHMOOD
Asst professor
Department ofSurgery, RMC

3. Objectives
• Define pain and its types.
• Explain the physiology of pain
• Explain pain as the “fifth vital sign”
• Enumerate factors influencing pain
• Enlist pain control strategies
• Elaborate rules for pharmacotherapy
• Introduce some pharmacological approaches to treating
pain.
• Algorithms for pain management
• Describe nursing interventions for pain control
• Enumerate complementary (non pharmacological
therapies used to control pain)

4. “Pain is a Sensory and Emotional experience,
associated with actual or potential tissue
damage or described in terms of such
damage”
(IASP)
Definition of pain?

5. Pain Types
• NOCICEPTIVE PAIN
– results from ongoing activation of mechanical, thermal, or
chemical nociceptors
– typically opioid-responsive
– eg. pain related to mechanical instability
• NEUROPATHIC PAIN
– spontaneous or evoked pain that occurs in the absence of
ongoing tissue damage,Dysfunction of the nervous system
– Abnormality in the processing of sensations
– Associated with medical conditions rather than tissue damage
– typically opioid-resistant***
– eg. pain secondary to nerve root injury
• Phantom Pain

6. Phantom Pain
• Occurs after the loss of a body part from amputation
• Patient “feels” pain in the amputated part for years after the
amputation has occurred
• May be controlled
Accessed 11 February 2009 from
http://www.pc.rhul.ac.uk/staff/J.Zanker/PS1061/L6/phantom.gif

7. Time-based classification of pain
• Acute: short-term; usually due to nociception
(tissue damage); resolves with healing.
• In back pain, Acute = < 4 wks
Sub-acute = 4-12 weeks
Chronic = > 12 weeks
• Chronic pain: pain lasting > 3-6 months
• Persisting pain
(NHMRC: acute pain guidelines)

8. “pain is whatever the experiencing person says it is,
existing whenever he says it does.” (McCaffery & Pasero,
1989).
“It is not the responsibility of clients to prove that they
are in pain; it is the physician’s responsibility to believe
them.” (Crisp & Taylor, 2005).

10. Factors Influencing Pain
• Age
• Gender
• Culture
• Meaning of pain
• Attention
• Anxiety
• Fatigue
• Previous experience
• Coping style
• Family and social support

11. Causes of Acute Pain
 Post-operative
 Burns
 Trauma
 Infective / Inflammatory conditions
 Ischaemic pain
 Visceral pain
 Obstetric - Labor

12. Causes of Post-Operative Pain
 Incisional skin and subcutaneous tissue
 Deep cutting, coagulation, trauma
 Positional nerve compression, traction & bed sore.
 IV site needle trauma, extravasation, venous irritation
 Tubes drains, nasogastric tube, ETT
 Respiratory from ETT, coughing, deep breathing
 Rehab physiotherapy, movement, ambulation
 Surgical complication of surgery
 Others cast, dressing too tight, urinary retention

13. Causes of Chronic Pain
 Cancer pain
 Cancer related
 From cancer therapy
 Cancer unrelated
 Non-cancer
 Nociceptive
 Neuropathic
 Idiopathic

14. Basics of Pain Management
• 1st step: is the good pain assessment.
• Pain medications must be taken:
 when the pain is first perceived.
• Doses of opioids are increased:
 with the patient’s report of pain
• Adjuvant medications are used for:
 opioid non-responsive & neuropathic pain.
• Non-pharmacologic approaches are always a part of
 any pain management protocol.

15. The “Costs” of Uncontrolled Pain
 Stress response  Hypothalamo-Pituitary-Adrenal axis:
 Disturbed cytokine cascade.
 Impairment of immune function.
 Increased catabolism.
 Negative nitrogen balance.
 Pain Chronicity.
 Cardiovascular
 Respiratory
 GIT
 Neuro-psychiatric
 Impairment of mobility, Gait disturbances.

16. Physiological effects of Pain
• Increased catabolic demands: poor wound healing,
weakness, muscle breakdown
• Decreased limb movement: increased risk of DVT/PE
• Respiratory effects: shallow breathing, tachypnea,
cough suppression increasing risk of pneumonia and
atelectasis
• Increased sodium and water retention (renal)
• Decreased gastrointestinal mobility
• Tachycardia and elevated blood pressure

17. Psychological effects of Pain
• Negative emotions: anxiety, depression
• Sleep deprivation
• Existential suffering: may lead to patients
seeking active end of life.

18. Immunological effects of Pain
• Decrease natural killer cell counts
• Effects on other lymphocytes not yet defined.

19. The ‘fifth’ Vital Sign
• Assessed in all patients
• Patient/client right to appropriate assessment
and management of pain

21. Acute Pain Management

22. Goal
• To provide patients with a level of pain control that
allows them to actively participate in recovery
– This level will be individual to each patient
• To minimize nausea and vomiting
• To minimize other side effects of analgesics
– Sedation
– Ileus
– Weakness
– Hypotension

23. Why all this is vital??
• Pain is a miserable experience
• Pain increases sympathetic output
– Increases myocardial oxygen demand
– Increases BP, HR
• Pain limits mobility
– Increases risk for DVT/PE
– Increases risk for pneumonia, atelectasis
secondary to splinting

24. Principles of Assessment
• Assess and reassess
• Use methods appropriate to cognitive status and context
• Assess intensity, relief, mood, and side effects
• Use verbal report whenever possible
• Document in a visible place
• Expect accountability
• Include the family

25. Assessment
• Location
• Intensity
• Onset
• Duration
• Radiation
• Exacerbation
• Alleviation

26. Good assessment = Successful management
Pain Assessment
N
R
S

27. Pain Assessment Tools
• In Adults: Self Report Measurement
Scales, such as Numerical Scales

28. Pain Assessment Tools
• In Pediatric Patients:
– Physiologic and Behavioral Indicators of Pain (
Infants, Toddlers, Nonverbal or Critically Ill
Children)
– Face Scale (Age 3-10 yrs)
– Visual Analogue Scales (Age 10-18)

29. • Subjective:
• Pain Scores:
• Unidimentional  Acute pain
• VRS, VAS & NRS.
• Facial expression.
• Multidimentional  Chronic pain
• McGill & Pain Inventory.
• Objective:
– Behavioral: refusal to move, cough & deep breath
– Physiological:  PR, RR, ABP, sweatiness & dilated pupils
– Neuro-endocrinal: RBS, Stress hormones
Pain Assessment

30. Numeric Rating Scale (NRS)
Visual Analogue Scale (VAS)
0 10
Pain Scores

32. Wong-Baker “Faces Scale”
Verbal scale
No
Pain
Mild Moderate
Severe
Pain

34. –Pharmacotherapy
– Anesthetic approaches
– Implantable devices
– Neurostimulation approaches
– Alternative approaches
– Surgical approaches
– Rehabilitative approaches
– Lifestyle changes
– Psychological approaches
Pain Control Strategies

35. Drug Strategies• Non Opioid Analgesics:
– NSAA
– NSAIDs
• Non-selective COX inhibitors
• Selective COX-2 inhibitors
• Opioids
– Weak Opioids.
– Strong opioids.
– Mixed agonist – antagonists
• Adjuvants
– Antidepressants
– Anticonvulsants
– Substance P inhibitors
– NMDA (N-methyl-D-aspartate receptor) inhibitors
– LA
– Drugs for Headache
– Drugs for Bone pain
– Others .

36. • Alternative medicine:
– Acupuncture
– TENS
– Cupping
– Chiropractice
• Physical Therapy
– ice, heat, massage
• Exercise
• Psychological therapy
– Cognitive-behavioral therapy
– Relaxation techniques
– Biofeedback
– Hypnosis
Non-Drug Strategies

37. Routes of Administration
• PO
• PR
• IV
• IM
• Transdermal
• Transmucosal
• Epidural
• Intrathecal

38. WHO step Ladder
1 mild
2 moderate
3 severe
Morphine
Hydromorphone
Methadone
Pethidine
Fentanyl
Oxycodone
± Adjuvants
Codeine
Hydrocodone
Oxycodone
Dihydrocodeine
Tramadol
± Adjuvants
ASA
Acetaminophen
NSAIDs
± Adjuvants

39. Pain
Step 1
Nonopioid
 Adjuvant
Pain persisting or increasing
Step 2
Opioid for mild to moderate pain
Nonopioid  Adjuvant
Pain persisting or increasing
Pain persisting or increasing
Step 3
Opioid for moderate to severe pain
Nonopioid Adjuvant
Invasive treatments
Opioid Delivery
Quality of Life
Modified WHO Analgesic Ladder
Proposed 4th Step
The WHO
Ladder
Deer, et al., 1999

40. How do we do it?
• Multimodal analgesia: Several analgesics with
different mechanisms of action, each working at
different sites in the nervous system

41. OPIOIDS
Efficacy is limited by Side-Effects
• The harder we “push” with single mode analgesia, the
greater the degree of side-effects
Analgesia
Side-effects

42. Multimodal Analgesia
• Lower doses of each drug can be used therefore
minimizing side effects
• With the multimodal analgesic approach there is additive
or even synergistic analgesia, while the side-effects
profiles are different and of small degree (Pasero & Stannard,
2012).
Analgesia
Side-effects

43. Systemic Analgesia
• Opioids
– Potent analgesics
– Drug of choice for moderate to severe pain
– Unfortunately, they are often the only drug
ordered
– Side effects:

44. Epidural Infusions
• Used for major surgery ie. Oncologic surgery,
thoracotomy
• Ideally placed pre-operatively and used in
combination with a GA for surgery and
continued ~ 2 days
• Usually patient is tolerating diet and
ambulation to chair when epidural is D/C

45. • Advantages:
– Patients can titrate their own analgesia
– Improved:
• Pain relief
• Pulmonary function.
– Decreased:
• Total daily dose.
• Over sedation.
• Postoperative complications.
Routes of Administrations - PCA

46. Miscellaneous Adjuvant Analgesics
• Pamidronate (Aredia)
• Zoledronic acid (Zometa)
• Strontium-89 (Metastron)
• Calcitonin (Calcimar) Not in cancer ? arthritis
• Capsaicin (Zostrix) scheduled in neuropathic pain
• Clonidine (Catapres) all forms
• Cannabinoid (Marinol)

47. Analgesics for Neuropathic Pain
• Tricyclic antidepressants
– nortriptaline (1st choice)
• Anticonvulsants
– Gabapentin, Carbamazepine, Pregaba
• Local anesthetics
– Parenteral, oral, topical
• Topical capsaicin
• Opioids for selected patients

48. Multidisciplinary Pain Clinic Personnel
• Physicians
– Neurosurgeon
– Orthopedic surgeon
– Anesthesiologist
– Neurologist
– Physiatrist
– Internal medicine
– Psychiatrist
– Addictionologist
• Nurses
• Psychologists
• Physical Therapist
• Occupational Therapist
• Vocational counselor
• Social worker
• Dietician
• Recreational staff
• Administrative support staff

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