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Oncologic Pain Management. Why?. After Incurability , Pain was ranked to be the most fearful and the most distressful symptoms Inadequate Pain control associated with profound alteration in nearly all aspect of wellness( activity-mood-rest-nutrition-sexuality..etc)
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Why? • After Incurability, Pain was ranked to be the most fearful and the most distressful symptoms • Inadequate Pain control associated with profound alteration in nearly all aspect of wellness( activity-mood-rest-nutrition-sexuality..etc) • Optimal Pain control, may hasten a return to normality (function-physiologic-spiritual-psychologic,economic,vocational,survivorship) • Adequate Pain control, influence outcome and survival…..How? • Of many negative associated with a diagnosis with cancer, Pain is one that not only need not to be endured, but when controlled makes other privations more manageable
Epidemiology of Cancer • Cancer is highly prevalent disorder • 6.35 million annual new cases world wide, 50% in developing country • 2nd most common cause of death • Poor outcome despite the aggressiveness of the new treatment. Poorer in developing country • 5y survival rate still 50% in USA and 33% in developed country for the last 40 years • One death for every ten deaths is due to cancer
Despite of the high mortality of cancer,intensive treatment applied hoping for cure,prolong survival or improve quality of life. Ironically Pain and disability are common outcome. Increased survival chance to experience Pain with other symptoms. Asthenia 90% Anorexia 85% Pain 76% Nausea 68% Constipation 65% Pain in cancer population: 1- 66% of all patients 2- 90% of advanced disease 3- 25% of pt.with active ttt. Have significant Pain Fortunately, 70-90% of pt. Got adequate pain control with stabilized guideline The rest 10-30% of pt. Need More invasive procedures Epidemiology of Cancer Pain
Cancer Pain Syndromes • Origin either (T-T-T) Tumor related: 60-80% of patients Therapy induced: 20-25% of patients a-Chemotherapy b-Radiotherapy c-Post surgical syndrome Totally unrelated: 3-10%
Barriers to Effective Cancer Pain Management • It is curious , indeed tragic, that despite the availability of straight forward, cost effective therapies, Cancer Pain remains undertreated.( R. Patt. The Patt center for Cancer) • The factors contributing to undertreatment are complex, but documented: 1-Knowledge Deficits 2-Beliefs 3-Attitude By: 1-Health Care Providers 2-Health Care System 3-Patient-Family members
A- Assessment General: Complete Broad Base Compassionate Goal:to orient pt.,family,and MRP to what realistically be accomplished. Operationally: Human Disease Pain 1-Psychosocial 2-Oncologic History 3-Pain History Supplement: Appropriate standardized pain questionnaire VAS BPI MPAC ESSCP Management of Oncologic Pain
a- Patient General History • Attention: Assessment is always two-way street. • Pre-assessment: Orientation of the problem • Psychosocial History: • Medical History: • Review System: too often overlooked.The main goal is the best quality of life possible.Failure of pain control is mainly due to other symptoms
Oncologic History • Prior Experience with Cancer (self-others) • Type, Extend (metastatic status) and Prognosis • Prior Antineoplastic Therapies and Outcome
Comprehensive Pain History • Premorbid Chronic Pain (3-10%) • Premorbid Alcohol or Drug Abuse • Pain Catalogue (number-location) • For Each Pain: -Onset and evolution -Site and radiation -Pattern -Intensity -Quality
Pain History Continue……. -Exacerbating factors -Relieving factors -How the pain interferes -Neurologic and motor abnormalities -Vasomotor changes -Other associated factors -Current analgesics -Prior analgesics
Physical Exam • It is non invasive, cost effective, time saving means of obtaining information • It may be challenging! • In one large study, 63% of pt. Referred to cancer pain service, pertinent new finding and 20% of them needed to initiate new antineoplastic therapy • General P.E and System review
P.E Continue…… • Special exam for: -Pain site -Tumor site -Musculoskeletal system -C.N.S Pain, in many time associated with subtle neurological deficit, identified by P.E Urgent diagnostic work up or oncologic emergencies may be the outcome of thoroughly history and physical exam
I’ve just done with my last chemo, I’ve to start again from scratch
Nociceptive A.Somatic -Bone Pain(the commonest) -Mechanism -Presentation B.Visceral -Presentation Neuropathic -Mechanism -Presentation .Emergency Cord compression Cauda Equina Syndrome 5% -Leptomeningeal mets! Important Pain Syndrome
Principles of Therapy 1- Keep Patient in Control 2-Focus in Whole Family 3-Utilize Team Approach 4-Usage of Multiple Methods for Treatment 5-Treatment of Other Symptoms 6-Environmental Therapy 7-Never Use Placebo 8-Refer When Pain Persists
Strategies to Attack Cancer Pain 1- Eliminating or modifying the source of pain 2- Modifying the interpretation of the pain message at the level of CNS 3-Interrupting the pain signal En route from periphery to the CNS
Multi-Modal Strategy • It has been proved that pain modification at multiple site in CNS is an effective therapy. 1-Modify the source of pain a-Surgery (acute pain-post surgical pain syndrome) b-Radiotherapy(post radiation pain) c-Chemo and Hormonal Therapy
2-Modify the interpretation of pain message • Pharmacological Analgesics • Psychological support and Relaxation tech. Pharmacological Analgesics General Principals: up to 90% success rate • First line of treatment WHO Analgesic Ladder and NCCN guideline • Oral route as long as possible
Continue…… • Avoid poly-pharmacy unless indicated • Avoid starting multiple drugs in the same time • New drug in small doses • Study the common group of drug in use • Have access to reliable inf.on uncommon drugs • Acknowledge and Manage the side effect
How to Choose the Analgesic ? WHO Step Ladder! It is an approach advocated toward cancer pain relief relies primarily on pain intensity. How to choose ? Mild vs Severe Acute vs Chronic When to switch? Who is better than WHO ?
The WHO Analgesic Ladder Severe Pain Strong Opioid++ 3 Moderate Pain Weak Opioid+ 2 Mild Pain Non-Opioid 1
Mechanism: Cyclooxygenase inhibitor (COX-1 and COX-2) PG degradation. Decrease pain by reducing pain receptor sensitivity, reduce the inflammatory process and edema Usage COX-2/COX-1 ratio Ceiling phenomenon Special Consideration High risk patients Monitoring Misoprostol Interindividual Variability Cox-1 sparing NSAID Ketorolac-Bromfenac Step 1: NSAID
Indication: Mechanism Weak vs Strong ! Potent vs less Potent Weak Opioid Intermediate Potency Almost in combination With other meds(NSAID..etc) Weakness due to the ceiling dose of NSAID or other When it is used (sole) in equianalgesic doses, control severe pain Step 2 and 3: Opioids
How To Use Opioids? • Pure agonist as first line of therapy. Higher incidence of psychotomimetic effect (dysphoria-hallucination) and nausea and vomiting with A-A • Never mix agonist with agonist-antagonist • Don’t mix two agonist • Don’t stay with weak agonist if pain not relieved • Oral route whenever possible • Round the clock strategy-----important
Continue…… • NEVER PRN. Continuous pain need continuous analgesic.Prevent resurgence of pain rather to treat it.PRN is illogical, cruel, perpetuate the fear and the memory of pain. It is only acceptable for break through pain.
Opioid Dose Titration • The correct dose of an opioid is that effectively relieves pain without inducing unacceptable side effect. There is no standard or set of doses of narcotics in cancer pain.There is a great variation between individuals. As pain changes through various stages of the disease, doses should be re-adjusted. Recommended doses are derived from acute single dose pain studies are not applicable to chronic cancer pain.The dose of the strong narcotic can be increased almost indefinitely without reaching a ceiling or plateau of maximum effect.(except. Meperidine-A/A) (A report of the Expert Advisory Committee on the Management of Severe Chronic Pain in Cancer Patients)
Continue……… • Consider adjuvant medication: 1-NSAID-----Bone Mets 2-Anti-depressant------Neuropathic Pain 3-Memberane stabilizer-------Neuropathic Pain 4-Treatment of side effect • Use narcotics as part of the: Total Pain Treatment
MS first choice Forms(IR vs SR) How often .ATC+PRN Dose calculation Dose titration(Key for succ.) Increase both ATC+PRN in 24 hr Severe Pain(7-10) 50-100% Moderate Pain(4-7) 25-50% Mild Pain (1-3) 25% Do you wake up pt.For dose! Why isn’t it working? -Inadequate Dose -Poor compliance -Vomiting-Drooling -Unresponsive Pain -Needs co-analgesic What about overwhelming Pain? 1- Oral Narcotics
Management of Opioid Side Effect • Constipation GI peristalsis- Secretion aggravated by fluid intake, physical activity and poor diet -Prevention -Treatment • Nausea & Vomiting Stimulation of chemoreceptor Prochlorperazine/Haloperidol Delayed gastric emptying Metchlopramide Increased vestibular sensitivity Dimenhydrinate If persist, modify the dose, opioid rotation, change the route
Sedation-Confusion 1-Prevention 2-Modify the doses 3-If persist revaluate 4-Opioid Rotation 5-Change the route Other Route: Why? Rectal : Oxycodon-Hydromorphone Transdermal : Fentanyl Patches.25,50,100ug/hr Subcutaneous Intravenous Continue……..
Interruption of Pain Signal and Anesthetic Intervention • Neuro-Axial Drug Delivery System • Neural Blockade
Neuro-Axial Drug Delivery System • Indication: • Route: 1-Epidural 2-Intrathecal (external vs internal pump) 3-Regional Plexus Catheter
Neural Blockade 1-With Local Anesthetic • Diagnostic • Prognostic • Pain Emergency • Muscle Spasm • Herpes Zoster • Premorbid Pain • Iatrogenic Pain
Neurolytic Neural Blockade • It is more often considered in setting of pain due to cancer as the ongoing tissue injury expected to progress • Types: • Pain-related indication: 1-Well Characterized 2-Well Localized (exception: Sympathetic blockade Stellate ganglion, Celiac plexus, Hypogastric plexus,lumber sympathetic) 3-Nociceptive rather than neuropathic pain • Patient- related indication:
Outcomes: Few controlled trials, no blinding or randomized, no controls for technique Efficacy: 50-80% of well selected pt. Duration: avg. 6 month. Complication:less than 5% in well selected pt.with fluoroscopy&CT. Hazards: Neurologic Deficit Damage to nonneurological tissue. Impermanece: non of the ablation tech.reliably produce permanent relief 4.New Pain: 2-28%. Neuritis and dysesthesia. It could be difficult to manage Neurolytic Blockade Contiue….