Cancer Pain

1. Cancer Pain Juliana Howes RN, BNSc, MN Clinical Nurse Specialist, Palliative Care

2. Outline • Examine classifications of cancer pain • Barriers to pain management • Tolerance, Dependence, Addiction • Pain Assessment • Tools (ESAS) • Special Populations • Common Medications • Opioids, Non-Opioids & Adjuvants

3. Outline Cont. • Treatments to reduce pain • Radiation Therapy & Chemotherapy • Guidelines for Use of Opioids • Managing common side effects • Constipation, dry mouth, N&V, sedation • Case Studies

4. Definition of Pain • “an unpleasant sensory and emotional experience associated with actual or potential damage, or described in terms of such damage” (IASP, 1979) • “whatever the experiencing person says it is, existing whenever the experiencing person says it does” (McCaffrey & Pasero, 1999)

5. Cancer Pain • 35% experience pain at diagnosis • 74% in advanced cancer (40-50% moderate to severe pain) • 85% at end of life • Cancer pain CAN be managed safely & effectively • Despite available options, up to 70% do not experience adequate relief

6. Total Pain

7. Classification of Pain Duration:Quality: * Acute * Nociceptive * Chronic - Visceral * Breakthrough - Somatic * Incident * Neuropathic

8. Nociceptive • Direct stimulation of afferent nerves in skin, soft tissue, viscera

9. Nociceptive: Somatic • Skin, joints, muscle, bone, connective tissue • Well localized • Deep - aching, throbbing • Surface – sharp • Often worse with movement • May be tender on palpation • i.e. surgical incisions, bone mets

10. Nociceptive: Visceral • Visceral organs • Poorly localized • Gnawing, deep, pressure, stretching, squeezing, cramping • Referred pain (i.e. left arm with MI, epigastric and back with pancreatic) • i.e. bowel obstruction, liver mets

11. Neuropathic • Abnormal processing of sensory input due to nerve damage/changes • Allodynia:pain from stimulus that does not normally provoke pain • Hyperalgesia:increased response to painful stimuli • Burning, stabbing, itching, numbing, shooting, tingling, electrifying • i.e. brachial plexopathy, cord compression

13. Barriers to Pain Management • Health Care Professionals • Lack of knowledge • Lack of assessment • Concern abut side effects • Concern about tolerance and addiction • Health Care System • Not a priority, issues with availability • Patients • Fear (condition worsening, addiction) • Not wanting to burden HCPs

14. Addiction • Chronic neurobiological disease with genetic, psychosocial and environmental factors • 3 C’s • Impaired Control over drug use • Craving/Compulsive use • Continued use despite consequences

15. Dependence • State of adaptation manifested by withdrawal syndrome from • Abrupt cessation • Rapid dose reduction • Administration of an antagonist

16. Tolerance • State of adaptation where exposure to drug causes decrease in its effect over time

17. Pseudos • Pseudo addiction • Mistaken assumption of addiction in patient seeking relief from pain • Pseudo tolerance • Misconception that need for increasing dose is due to tolerance rather than disease progression

19. Assessment - ESAS • Initial and routine assessment of pain & other symptoms • Body diagram to show location of pain

20. Assessment – Nonverbal or Cognitively Impaired Patients • Gold Standard is self-report • High potential for unrelieved & unrecognized pain • Non-verbal Cues • Facial Expressions • Body Movements • Protective Mechanisms • Verbalizations • Vocalizations • Family observations/perceptions

22. Commonly Used Opioids • Morphine • Hydromorphone • Codeine • Oxycodone • Fentanyl

23. Morphine • Moderate to severe pain • Gold Standard - affordable & available • Measure for dose equivalence • Active metabolites – toxicity in elderly & renal impairment • Oral (IR/CR/Elixir), Parenteral, Rectal, Intraspinal

24. Hydromorphone • 5x more potent than morphine • Oral (IR/CR/Elixir), Parental, Rectal, Intraspinal • Better tolerated in elderly

25. Codeine • Mild to moderate pain • 10x weaker than morphine • Usually in combination with Tylenol • Ceiling effect at 600mg/24 hrs, max 360mg/d if Tylenol #3 • Metabolized into active form (morphine) by liver • Up to 10% of population unable to convert to active form – no pain relief • Oral (IR/Elixir), Parenteral

26. Oxycodone • 1.5-2x more potent than morphine • Oral (IR/CR) • Often combined with Tylenol (Percocet) • ?more issues with addiction

27. Fentanyl • Not for opioid naïve patients • Difficult to convert as 25 mcg patch = 45-135 mg PO morphine *Tip: Duragesic 25mcg/hr patch = Morphine 25 mg SC/24hrs • Patch difficult to titrate as it takes 12-24 hours to see effect of change • Transdermal, Sublingual, Parenteral

28. Non-Opioids • Mild to moderate pain • Inflammation, Bony pain • Used as adjuvant with opioids • Acetaminophen: max 4g/d, 3 g/d in frail elderly, Liver toxicity • NSAIDs: inhibit synthesis of prostaglandins preventing contribution to sensitization of nociceptors • i.e. Ibuprofen, Naproxen, COX2 (celebrex) • Adverse effects: GI bleed, increased BP, decreased renal function, impaired platelet function

29. Adjuvants • Antidepressants • Anticonvulsants • Corticosteroids • Local Anesthetics • Anticancer therapies

30. Antidepressants • TCAs i.e. amitriptyline, nortriptyline for neuropathic (burning) pain • Anticholinergic effects – sedation, constipation, dry mouth • Start low and titrate as needed q2-3 days

31. Anticonvulsants • Neuropathic (shooting) pain • i.e. Gabapentin – start at 100mg TID or 300mg OD and titrate up to 3600mg/day • Decreased dose in elderly/renal impairment • Side effects can include sedation & dizziness

32. Corticosteroids • Pain due to spinal cord compression, headache due to increased ICP, bone mets • Can be used to stimulate appetite • i.e. Decadron 4mg to 16mg/day • Side effects include hyperglycemia, psychosis, insomnia

33. Anticancer Therapy • Palliative Radiation: bone pain, reduce tumour size to decrease pain (i.e. chest pain in lung ca) • Palliative Chemotherapy: reduce tumour size if adequate performance status and not significant impact on QOL

34. Guidelines for Use • Constant or frequent pain requires regular medication • Oral route preferred • Start with IR to allow for titration • Use opioid with best analgesia and fewest side effects • A breakthrough dose should be available as needed • 10% of daily total or 50% of q4h dose • CMAX: PO 1h, SC 20-30 min, IV 5-10 min • Treat opioid side effects from the start • Regular laxative order, PRN antiemetic • Adjuvants are often essential for adequate pain control

35. Guidelines Cont. • Is patient opioid naïve? • Opioid still required if moderate to severe pain, start low and titrate • Choose route of administration • Ability to swallow, absorption, compliance, pt. preference • Determine dosing schedule • IR q4h with BT doses q1h until relief • Based on BT usage, titrate up • When adequate dosage found, can switch to long acting medication

36. Titration • If requiring more than 3-4 breakthrough in 24 hours: • Look at pattern and reassess pain • Increase q4h dose and BT accordingly • Add BTs to q4h dose or increase by 1/3 • i.e. Morphine 5mg PO q4h and 2.5mg PO q1h, pt used 6 BTs = 15mg • 30mg + 15mg = 45mg /6 doses • New dose would be 7.5 mg PO q4h

37. Converting • Once stabilized, can switch to long acting BID • Take total daily dose and divide for BID • i.e. Morphine 10mg PO q4h = MS Contin 30 mg PO q12h • If switching to a new opioid, need to consider incomplete cross-tolerance • Tolerance to new opioid may be less and so can achieve pain relief with lower dose • Thus need to reduce dose of new opioid by 25-50% (usu. cut by ~ 1/3)

38. Pumps • Allows for self-administration of parenteral BTs • More consistent dosing as continuous • CADD pump

39. Equianalgesic Table

40. Using the Table Convert Percocet 2 tab PO q4h to Morphine (1 Percocet = Oxycodone 5mg + Tylenol 325mg) Oxycodone 10mg x 6 doses = 60mg From Table Oxydone 5mg = Morphine 10mg Thus, Oxycodone 60mg = Morphine 120mg This would be Morphine 20mg PO q4h, but consider incomplete cross-tolerance Therefore, Morphine 15mg PO q4h with 7.5mg q1h PRN

41. Suggestions • Initial dosage of strong opioid in opioid naïve patient • Fit: Morphine 5-10mg PO q4h or equivalent • Frail: Morphine 2.5-5mg PO q4h or equivalent • Dosage of strong opioid in patients already on opioids • If on weak opioid (i.e. Tylenol #3), not opioid naïve! • Determine starting dose by using equianalgesic table

42. Side Effects of Opioids • Common: constipation, dry mouth, nausea, vomiting, sedation • Less Common: confusion, pruritis, myoclonus, hallucinations, urinary retention • Rare: respiratory depression

43. Constipation • Opioids inhibit peristalsis and increase re-absorption of fluids in the lining of the gut • Standing order if on opioids • Senokot 1-6 tab BID + Stool softener • Lactulose 15-45 cc OD to TID

44. Sedation and N&V • Commonly experienced in first few days of taking opioids or after increasing dose • Body will adjust and these symptoms will improve • Minimize other meds that contribute to drowsiness (i.e. Benzodiazepines) • PRN anti-emetic (i.e. haldol 1mg PO/SC/IV, stemetil 10mg PO/IV/PR, maxeran 10 mg QID)

45. Dry Mouth • Difficult to avoid • Strategies to minimize include: • Frequent mouthcare • Fluids/Ice Chips • Sugarless gums • Artificial saliva (i.e. Moi-Stir)

46. Summary • Pain Orders should include: • Regular Analgesic • PRN Analgesic • Standing Laxative • PRN Anti-emetic • Treat side effects from the beginning • Consider type of pain & use adjuvants • Ongoing re-evaluation

47. Case Study #1 • Mr.R, 46 yrs, met. lung ca., currently taking Tylenol #3 2 tab q4h and using 9 extra tablets/day for breakthrough. He has no difficulty swallowing the Tylenol #3. • What is the problem with this amount of Tylenol #3? • What are your recommendations? Calculate and provide new orders

48. Case Study #1 Cont. • After titrating his medication, Mr.R was comfortable for a time. However, he has begun to complain of right arm weakness and shoulder pain causing shooting pain down his arm. • What type of pain do you suspect he is experiencing? • What medication and dose would you recommend?

49. Case Study #2 • Ms.Q, 63 yr old, met. breast ca., has been taking MS Contin 30mg q12h and has morphine 5mg tablets available for BT. She is using about 4 tab/day, but still having uncontrolled pain • Main pain to low back that radiates along the left side, an MRI confirms bone met to L4 (no cord compression)

50. Case Study #2 • What changes would you make to her pain medication? • What other treatments might be considered? • Ms.Q’s condition deteriorates and she is no longer able to swallow her medications – What would be the SC/IV dose?