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

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

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

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)

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

Total Pain Suffering of the whole person If challenges controlling physical pain, question if other areas need attention Psychological distress in 40-80%, often highest when confined to bed Need to actively listen to patient, ask how they are coping and feeling I’ve had patients where it has been extremely difficult to control their pain, but spending time with them each day and discussing their fears had a huge impact on their physical well-being, such that they were able to go home to die as per their wishes instead of remaining in hospital.

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

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

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

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

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

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

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

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

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

Pseudos Pseudo addiction Pseudo tolerance 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

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

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

Commonly Used Opioids Morphine Hydromorphone Codeine Oxycodone Fentanyl

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

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

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

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

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

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

Adjuvants Antidepressants Anticonvulsants Corticosteroids Local Anesthetics Anticancer therapies

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

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

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

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

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

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

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 New BT should be 3.75-4.5mg, but if using pills only available in 5mg tabs – so leave at 2.5 or increase to 5mg depending how pt.’s response to the BT

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)

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

Equianalgesic Table PO SC/IV Codeine 100mg --- Morphine 10mg 5mg Oxycodone Hydromorphone 2mg 1mg

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

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

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

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

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)

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

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

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 Exceeds 4g/d of Tylenol, exceeds ceiling dose of codeine Switch to morphine Codeine 360 + 270 = 630 Thus, morphine 63 mg/d Cut by ~1/3, this is not exact Morphine 45mg/d Morphine 7.5 mg PO q4h, morphine 5mg PO q1h PRN OR can use dilaudid 1.5mg q4h with 0.5 or 1 mg BT

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? Neuropathic, likely r/t brachial plexopathy (damage to the nerves as tumour invades or compresses) Shooting – anticonvulsant, start gabapentin at 300mg OD

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)

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? Switch to IR to allow for titration Morphine 60 + 20 = 80/day Could stick with morphine..and use 12.5 or 15mg q4h Easier to change to dilaudid 80 /5 = 16mg/d Cut by ~30% Therefore, dilaudid 12mg/day = 2mg q4h Radiation therapy!! SC/IV dose would be dilaudid 1mg SC/IV q4h