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A Practical Approach to Cancer Pain Management. The Problem:. One out of three people in the U.S. will develop cancer One out to two people who develop cancer, will die of their disease Three out of four patients who die of cancer, will have significant pain during their illness.
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The Problem: • One out of three people in the U.S. will develop cancer • One out to two people who develop cancer, will die of their disease • Three out of four patients who die of cancer, will have significant pain during their illness
Impact of Uncontrolled Pain: • Physical: • symptom complex (fatigue, depression, NC) • decreased function (work, AIDLs, ADLs) • Emotional • total mood disorder • spiritual distress • Social • family interactions • alters support structures
Pain Assessment: • Intensity • Etiology • Type
Measurement: • Scales: • Numeric rating scales • Visual analogue • Descriptive • Outcome Measure: • Pain intensity • Distress • Relief • Interference • Breakthrough dosing • Tools: • Brief Pain Index • Memorial Pain Assessment Card
Clinically Important Questions: • Current pain level • Average pain level • Worst pain level • Pain relief with medications
Etiology: • Treatable Causes: • pathologic fracture • bone met • chest wall recurrence • Emergent: • cord compression • brain met
Nociceptive Pain • Mechanism: Pain receptor activation • Subtypes: • Somatic • most common type in cancer patients • bone mets most common cause • characterized by aching, throbbing, gnawing • Visceral • deep, squeezing, crampy
Neuropathic Pain: • Mechanism: Damage to receptor or nerve • Frequently unrecognized • Types of Syndromes: • Peripheral • Drug induced (Cisplatin, Taxol) • Central • Cord compression
Neuropathic Pain Syndromes: • Post-amputation Limb Pain • Post-thoracotomy Pain • Post-mastectomy Pain • Brachial Plexopathy • LS Plexopathy • Celiac Infiltration
Assessment of the Patient: • Medical Problems • Psychological Function • Physical Function • Cognitive Function • Support Services • Financial Services • Educational Status
Skill Sets Required for Adequate Pain Control: • Develop a framework for writing prescriptions • Write a fixed dose regimen • Calculate an appropriate breakthrough dose • Convert from one opioid to another • Dose titrate • Understand the issues of substance abuse
WHO Step Ladder of Pain Management: • Step 1 • NSAID • Acetaminophen • Non-pharmacological techniques • Step 2 • Mixed opioid + non-opioid • Low dose pure opioid (oxycodone) • Alternative pharmacological agents (i.e. Ultram) • Step 3 • Pure opioids • Adjunctive medications • Invasive procedures
Step 3: Basic Rules for Opioid Administration • Goal: Controlled Pain (4 or fewer rescues) • Dose Escalation: Quickly until controlled pain • Maximum Dose: Does not exist • Side Effects: • Accommodation in 7-10 days • Treat aggressively • Bowel Regimen
Basic Rules for Opioid Administration: • Use oral or transdermal formulations if possible • Start with immediate release formulations in patients with significant pain • Use medications around-the-clock for constant pain (fixed dosing) • Fixed dose interval should be based on T1/2 of the agent • Rescue dose interval should be based on time to peak effect
Meperidine: • By product - normeperidine • T1/2 of normeperidine is longer than meperidine • Normeperidine has a neuroexcitatory effect • Toxicity is seen when administered over a prolonged period or in patients with renal insufficiency
Fixed Dose Administration: • Goal: to maintain opioid levels within the therapeutic window • Fixed dosing allows a steady state to be achieved • Once steady state is achieved, dose modifications can be made in a calculated way
PRN Dosing: • Patients take pain medication as needed, thus they are in pain when they take a dose. • Patients are in pain more frequently • They are more likely to have side effects
Fixed Dosing:Medication Half Life • Immediate Release: • Morphine: 3-4 hours • Dilaudid: 2-4 hours • Oxycodone: 3-4 hours • Hydrocodone: 3-4 hours • Sustained release: • Morphine • MS Contin: 8 to 12 hours • Avenza, Cadian: 24 hours • Oxycodone • Oxycontin: 8 to 12 hours • Fentanyl • Duragesic Patch 18 hours
Write a Fixed Dose Prescription for the Following: • Morphine Sulfate IR 30 mg tabs • MS Contin 30 mg tabs • Dilaudid 4 mg IR tabs • Duragesic 25 ug patch • Oxycontin 20 mg tabs
Write a Fixed Dose Prescription for the Following: • Morphine Sulfate IR 30 mg po q 4 hours ATC • MS Contin 30 mg po q 12 hours • Dilaudid IR 4 mg po q 3-4 hours ATC • Duragesic 25 ug patch to skin q 72 hours • Oxycontin 20 mg po q 12 hours
Breakthrough Dosing: • Breakthrough medications should be fast acting • Dose interval based on Time to Peak Effect • Dose should be 10-15% of the 24 hour opioid fixed dose total
Example Breakthrough Dosing: • MS IR 60 mg po q 4 hours • 24 hour fixed total = 360 mg • MS IR 30 mg po q 1-2 hours • Dilaudid 16 ug po q 4 hours • 24 hour fixed total = 64 ug • Dilaudid 6 ug po q 1-2 hours • Duragesic 100 ug patch q 72 • 24 hour morphine equivalent 200-300 • MS IR 20-30 mg po q 1-2 hours
Acute Management:Moderate to Severe Pain • Previously on Mixed Agents: • Start with MSIR 30 mg po q 4 hours • With MS IR 15 mg po q 1-2 hours prn • Opioid Naive or Frail/Elderly • Start with MSIR 15 mg po q 4 hours • With 1/2 of a 15 mg tab po q 1-2 hours prn
Equi-analgesics: • Need to be able to convert from one agent to another • Most tables compare to a specified dose of morphine • Equi-analgesics charts are rough estimates • Considerable inter-patient variability exists • General rule: when converting form one agent to another, find the equi-analgesic dose and decrease by 25% due to non-cross resistance
Key Equi-analgesics Ratios • Morphine to Dilaudid: 5 to 1 • Morphine to Hydrocodone: 1 to 1 • Morphine to Oxycodone: 1 to 1 • Morphine to Duragesic: 2-3 to 1
Method: • Step 1: • Calculate the 24 hour fixed dose total • Step 2: • If necessary, convert to morphine equivalents • Step 3: • Using the appropriate ratio, calculate the 24 hour fixed dose equivalents of the new agent • Step 4: • Divide the 24 hour fixed dose total by the number of doses per day
Conversion Examples: • Convert MS IR 30 mg po q 4 hours to Dilaudid • Convert MS IR 30 mg po q 4 hours to Duragesic • Convert Dilaudid 8 mg po q 3 hours to Duragesic
Conversion Example 1: • Step 1: (calculate the 24 hour fixed dose total) • Morphine 30 mg po q 4 hours = 30 x 6 =180 mg • Step 2: (convert to morphine equivalents) • Not needed • Step 3: (apply appropriate ratio) • 180 x 1/5 = 36 mg of Dilaudid • Step 4: (divide by number of doses per day) • 36 / 6 = 6 mg every 4 hours
Conversion Example 2: • Step 1: (calculate the 24 hour fixed dose total) • Morphine 30 mg po q 4 hours = 30 x 6 =180 mg • Step 2: (convert to morphine equivalents) • Not needed • Step 3: (apply appropriate ratio) • 180 / 2-3 = 60-90 ug of Duragesic • Step 4: (divide by number of doses per day) • Not needed
Conversion Example 3: • Step 1: (calculate the 24 hour fixed dose total) • Dilaudid 8 mg po q 4 hours = 8 x 6 = 48 mg • Step 2: (convert to morphine equivalents) • 48 x 5 = 240 mg • Step 3: (apply appropriate ratio) • 240 / 2-3 = 80 - 120 mg of Duragisic • Step 4: (divide by number of doses per day) • Not needed
Titration Schema: Initial Fixed and Rescue Dose Controlled Pain Moderate Pain Severe Pain No Change 25% Increase 50% Increase
Example 1: • 65 yo with bone pain due to metastatic prostate cancer • Current regimen: • MSIR 30 mg po q 4h ATC • MSIR 15 mg po q 1-2h prn • Reports pain 1/10 with 10 rescue doses/24h • Calculations: • 24h narcotic total = (30mg x 6)+(15mg x 10) = 330mg • New Fixed dose = 330 / 6 = approx 60 mg • New Regimen: • MSIR 60 mg po q 4h ATC • MSIR 30 mg po q 1-2h prn
Example 2: • 65 yo with bone pain due to metastatic prostate cancer • Current regimen: • MSIR 60 mg po q 4h ATC • MSIR 30 mg po q 1-2h prn • Reports pain 5/10 with 8 rescue doses/24h • Calculations: • 24h narcotic total = (60mg x 6)+(30mg x 8) = 600mg • New 24h narcotic total = 600 + 150 = 750 mg • New Fixed dose = 750 / 6 = 120 mg • New Regimen: • MSIR 120 mg po q 4h ATC • MSIR 75 mg po q 1-2h prn
Example 4: • 65 yo with bone pain due to metastatic prostate cancer • Current regimen: • MSIR 60 mg po q 4h ATC • MSIR 30 mg po q 1-2h prn • Reports pain 9/10 with 8 rescue doses/24h • Calculations: • 24h narcotic total = (60mg x 6)+(30mg x 8) = 600mg • New 24h narcotic total = 600 + 300 = 900 mg • New Fixed dose = 900 / 6 = 150 mg • New Regimen: • MSIR 150 mg po q 4h ATC • MSIR 90 mg po q 1-2h prn
Long Acting Formulations: • Should be used in controlled pain only • Determine the amount of narcotic needed to control pain with short opioids then convert to long acting formulations • If pain becomes uncontrolled, switch to short acting agents, titrate rapidly, then convert back to long acting agent
Sustained Release Formulations: • Morphine • Oxycodone • Fentanyl • Dilaudid
Example 5: • 65 yo with bone pain due to metastatic prostate cancer • Current regimen: • MSIR 60 mg po q 4h ATC • MSIR 30 mg po q 1-2h prn • Reports pain 1/10 with 1-2 rescue doses/24h • Calculations for MSSR with half-life of 8-12 hrs: • 24h narcotic total = (60mg x 6) =360 • New Fixed dose = 360 / 2 = 180 mg • New Regimen: • MSSR 180 mg po q 12h ATC • MSIR 30 mg po q 1-2h prn
Transdermal Fentanyl • Patch Size: 25, 50, 75 and 100 micrograms • Duration of Action: 72 hours • Advantages: • Easy, convenient use • No need to remember to take meds • Disadvantages: • Difficult when using high dose of narcotics • Thin patients with little subcutaneous tissue
Consider Patch in the Following Patient Populations: • Non-compliant patients • Patients unable to take oral medications • Question of drug abuse • Question of cognition
Conversion Factor: 100 mg Morphine 50 micrograms Fentanyl
Example 6: • 65 yo with bone pain due to metastatic prostate cancer • Current regimen: • MSIR 60 mg po q 4h ATC • MSIR 30 mg po q 1-2h prn • Reports pain 1/10 with 1-2 rescue doses/24h • Calculations for Fentanyl (Duragesic®) Patch: • 24h narcotic total = (60mg x 6) =360 • New Fixed dose = 360 / 2 = 150 g • New Regimen: • Duragesic 150 g to skin q 72h ATC • MSIR 30 mg po q 1-2h prn
Use: Pain Emergency Unable to take po High narcotic needs Toxicity from po Relative Strength: IV 3 times more potent than po Role of PCA Schedule: Continuous Infusion with bolus for rescue Rescue: Rapid Peak Fast Clearance q 10 minutes Hourly dose equal hourly rescue IV/SC Narcotics
IV Example 1: • Pt admitted for elective surgery • Controlled pain on: • MSIR 60 mg po q 4h ATC • MSIR 30 mg po q 1-2h prn • 24 hour narcotic total = 360 mg • IV equivalent = 360 / 3 = 120mg/24h • Hourly rate = 120 / 24 = 5 mg h • Order: • MS 5 mg/hr CIV • MS 1 mg q 10 minute IVB prn
Pain Emergency: • Step 1: Narcotic Load • Narcotic Load using IV boluses until pain level reduced by 50-75% • Step 2: Calculate Maintenance Dose • MD = Load/2 x half-life • Step 3: New Order • MD in mg/hr • rescue - bolus q 10 minutes
Pain Emergency • High Dose Decadron • Anesthesiology Consult • Neurosurgery Consult
Barrier Reduction: • Patient education: • Endpoint to be assessed: • Beliefs • Communication skills • Knowledge pain control • Outcome of interventions: • Improve beliefs and adherence • Results variable for improved pain control • Physician and staff education: • Endpoints to be assessed: • Knowledge • Attitudes • Practice patterns • Pain control