Cancer pain and its management

1. Cancer pain and its management Dr.Vincent Appathurai M.B.B.S. D.T.M. Principal Medical officer, BLH Presented at Annual Conference, BMA 28th Oct 2007

2. “Pain is a greater Lord of mankind than even death itself” - Albert Schewitzer

3. Introduction • Cancer accounts for 12.5% deaths worldwide more than HIV/AIDS,TB, Malaria put together • By 2020, 15 million new cases will occur each yr in the world, 1 million of them in African countries • An estimated 80% of people with cancer present to heath services with late stage cancer when pain relief and palliation is the only option • Hence cancer pain management is an integral part of primary care

4. Definition of pain • An unpleasant sensory and emotional experience associated with actual or potential tissue injury or described in terms of such damage (International Association for the Study of Pain ) IASP. • The intensity of pain varies with the degree of injury, disease or emotional impact.

5. Pain is a psychosomatic phenomenon • Pain is what the patient says it is. • Pain is a self reported subjective experience involving sensory neural transmission of the afferent noxious stimulation that has an expression of the person’s reaction to the pain • Pain is a psychosomatic phenomenon modulated by mood, morale and meaning ( Dr.Robert Twycross )

6. Concept of Total Pain PHYSICAL TOTAL PAIN PSYCHOLOGICAL SOCIAL SPIRITUAL

7. Physiology of pain • It is important to understand the underlying patho-physiological factors before attempting to treat pain in a logical and systematic way. • Peripheral receptors and pathways • Central pathways • Modulatory mechanisms

8. Physiology of pain • Neurotransmitters and receptors • Prostaglandins and bradykinin • Opioid receptors • Glutamate and NMDA receptors • The role of sympathetic nervous system • Neuropathic pain • Nerve compression pain • Sympathetic mediated pain

9. Pain in Cancer • May not have pain !!! • Most do have pain- 2/3rd with advanced cancer Number of pains • 1/5th have one pain • 4/5th have 2 or 3 pains • 1/3rd have 4 or more pains • Not all pain in cancer is caused by cancer

10. Top 10 cancer pains Directly related to the cancer ( 4 of them) • Bone • Visceral • Neuropathic • Soft tissue ( All constitute 30-40% of pains )

11. Top 10 cancer painsCancer pain with debility ( 6 of them ) • Immobility, Constipation • Myo- fascial, Cramps • Oesophagitis • Degeneration of spines ( All constitute 10-20% ) • Pain associated with chemotherapy, radiotherapy, surgical intervention. • Others- Difficult pains – complex 10%

12. Aetiology of cancer pain • Infiltration of the viscera • Bony metastases • Smooth muscle spasms • Muskulo- skeletal pains • Infection • Nerve compression pain • Unrelated pains

13. Assessment of pain • Good history taking - Pain is the fifth vital sign • Site • Duration • Onset • Quality of pain • Aggravating factors • Relieving factors

14. Assessment of pain • Temporal pattern (acute, chronic, sub acute, breakthrough pain, incident pain) • Interference with daily living • Sleep • Psychological status • Response to current and previous therapy

15. A systematic approach • Evaluation • Explanation • Management • Monitoring • Attention to detail

16. Tools used in assessment of pain Numerical scale 0 1 2 3 4 5 6 7 8 9 10 No pain Worst pain

17. Categorical scale None (0) Mild (1-3) Moderate ( 4-6 ) Severe ( 7-10 )

18. Visual Analogue scale _________________________________ No pain (mark) worst pain

19. Pain faces scale used in children - Wong - Baker 0 - very happy, no hurt 2 - hurts just a little bit 4 - hurts a little more 6- hurts even more 8 – hurts a whole lot 10 – hurts as much as it can ( crying )

20. Management of pain - Pharmacological - Non - pharmacological

21. Pharmacological Management WHO Analgesic Ladder 1980’s Three steps Mild pain = Non- opioid + or – Adjuvant Mod.pain = Weak opioids + or – Non-opioid + or – Adjuvant Severe pain = Strong opioids + or – Non-opioid + or - Adjuvant

22. WHO Analgesic Ladder • Principles are Five - By mouth - By the clock - By the ladder - For the individual - Attention to detail

23. WHO Analgesic Ladder

24. Outcome (WHO analgesic ladder) • Relieves pain effectively in 80-90% of cancer patients • 10-20% of pains are difficult pains • Good relief of pain in 75% of terminally ill patients • Consider adding non-opioids and adjuvant for effective control

25. Principles in use of morphine • Administer in simple aqueous solution 10mg/5ml • Begin with 5-10mg every 4 hrs orally • Adjust after 24hrs- titrate dosage. • No ceiling effect - • Dosage is usually 100-500mg

26. Principles in use of morphine • A double dosage at bedtime 22.00hrs • Calculate LA twice daily dosage after assessment e.g 120mg total = 60mg b.d • Antiemetic for nausea-Haloperidol 1-2.5mg is best, but often metoclopramide is used. • Laxative-senna or bisacodyl or liquid paraffin

27. Principles in use of morphine • One sixth of original dose for breakthrough pains • If unable to take oral morphine use parenteral s.c or i.m – 1:3 or 1:2 or rectal • Use syringe driver under supervision • Addiction does not occur • Tolerance does occur • Some physical dependence may occur

28. Side effects of morphine • Nausea and vomiting • Confusion • Sedation • Constipation • Hallucinations • Constricted pupils • Biliary colic

29. Side effects of morphine • Itching • Sweating • Myoclonus • Convulsions • Dry mouth • Histamine release ( broncho-constriction ) • Pulmonary oedema

30. Treatment of side effects • Opioids used according to guidelines rarely cause severe toxicity or addiction particularly morphine • Reduction of dosage is all that is necessary e.g myoclonus • Antidote treatment is indicated only, if severe respiratory depression is present • Naloxone o.4mg dil in 10ml N.saline given as 0.5ml/ 2mt intervals until resp. normal

31. Non-opioids • Aspirin 600mg p.o every 4 hours • Paracetamol 1g p.o every 4hours • NSAID’s • Ibuprofen 400mg p.o tds • Indomethacin 50mg p.o tds • Diclofenac 50mg p.o tds

32. Other Adjuvants • Antidepressants- Amitriptyline • Anticonvulsants-carbamazepine, Sodium Valproate • Corticosteroids- Prednisolone, Dexamethasone, methyl prednisolone • Muscle relaxants-Diazepam or Baclofen • Bisphosphonates- Disodum pamidronate

33. Weak opioids • Codeine • Hydrocodone • Propoxyphene • Tramadol • Used in step 2 for mild to moderate pain • Add non opioid and adj. to optimize effect

34. Strong opioids • Short half life Long half life -Morphine - Methadone -Hydromorphone - Levorphanol Oxycodone - Transdermal fentanyl Meperidine Fentanyl

35. Corticosteroids in cancer pain management Use only in specific indications • Spinal cord compression, Nerve compression pain and weakness • Lymphangitis carcinomatosis • Raised intracranial pressure • Superior vena cava syndrome • Capsular stretching of internal organs

36. Dosage of corticosteroids • Large dosage regimen Dexamethasone 100mg stat followed by 96mg/day in divided doses, reduced over weeks, supplemented by other analgesic approach such as radiotherapy • Low dosage regimen Dexamethasone 1-2mg once or twice daily

37. Anaesthetist’s role • In intractable, opioid non responsive advanced cancer pain, consider • Brachial plexus block • Intercostal block • Coeliac plexus block • Lumbar plexus block • Perineal and saddle block • Intrathecal morphine

38. Non-pharmacological methods • Distraction, Music therapy • Relaxation therapy- yoga, meditation • Cutaneous stimulation –TENS • Acupuncture • Psychotherapy and counselling • Hypnosis • Mechanical therapies – massage, exercise, immobilization, orthopaedic aids and mobility devices

39. Barriers to pain management • Inadequate pain assessment • Inadequate knowledge about cancer pain and its treatment • Patient and physician’s attitudes and fears about pain and opioids – opiod phobia • Poorly accessible and unavailable pain management services ( anaesthetists ) • Lack of pain clinics services

40. Why pain relief ? • Despite all available methods of pain control, too many people are suffering from unrelieved pain particularly those affected by Cancer and HIV/AIDS • The quality of life in these pts depends on effective pain relief • Africans die in pain because of fears of opiate addiction – opiophobia ( APCA, 2nd conf 2007 ) • Pain is under diagnosed and under treated

41. Why pain relief? • It is a basic human right -- Declaration at APCA, 2nd African palliative conference - Sept 2007, Nairobi • Home based care patients especially those with advanced cancer and HIV/AIDS need morphine regularly • We must make sure that supply of all essential analgesics, particularly morphine is made available in district, primary hospitals and clinics in our country – Essentially Liquid morphine and oral preps • Appropriate legislation must be in force e.g. Uganda • Botswana must make an effort to procure liquid morphine ( NASCOD, MOH, CMS initiative)

42. References 1) Twycross R, Wilcock A. Symptom management in advanced cancer (3e),Abingdon, Oxon: Radcliff medical press, 2001,pp 51-58 2) Dr. Ian Back, Topics in palliative care, Pain,1997 3) Eduardo Bruera et al, Palliative care in the developing world: Cancer pain, pp 107-124, IAHPC, 2004 4) Marie Fallon, Bill O’Neill, ABC of Palliative care, Pages 2-4,BMJ Books, 1998

43. References 5) Cancer pain relief, edn 2. Geneva: World Health Organization, 1996 6) International Association for the study of pain. Pain 6:249-252, 1979 7) Palliative Care Training Manual, MOH, Botswana. 3rd draft, April 2007

44. KEALEBOGA Thank you