PAIN MANAGEMENT PGY-1. Aaron D. Storms, MD Carin van Zyl, MD Adult and Pediatric Palliative Care, LAC+USC Keck School of Medicine of USC

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1 PAIN MANAGEMENT PGY-1 Aaron D. Storms, MD Carin van Zyl, MD Adult and Pediatric Palliative Care, LAC+USC Keck School of Medicine of USC

2 Perception Matters A builder aged 29 came to the accident and emergency department having jumped down on to a 15 cm nail. As the smallest movement of the nail was painful he was sedated with fentanyl and midazolam. The nail was then pulled out from below. When his boot was removed a miraculous cure appeared to have taken place. Despite entering proximal to the steel toecap the nail had penetrated between the toes: the foot was entirely uninjured. Fisher et al. BMJ 1995;310:70

3 Perception Matters Sensory stimuli (visual, auditory, olfactory) impact pain perception Pleasant/unpleasant emotions modulate pain perception Cognitive processes (e.g. attention, expectations, catastrophizing) play a role Depressed mood and anxiety about pain might be associated

4 Total Pain Recognition that pain is not purely a physical experience it has psychological, social, emotional and spiritual components Zaza et al. J Pain Symptom Manage IASP. Total Cancer Pain factsheet

5 Pain Assessment Key Points Find the reason for the (worsening) pain Does new/worsening pain correlate with disease? Same pain or different? (type of pain, location) Cancer patients are at risk of many painful complications (e.g. bowel obstruction, SBP, fractures, metastasis to new areas, liver capsule distension, constipation) Whole-person assessment ideally by a multidisciplinary team Coping, anxiety, depression, psychosocial stressors, expectations regarding pain, family, etc.

6 Pain Management

7 Treatment of pain in short prognosis patients Focus on comfort Less emphasis on titrating to function, especially at end of life Opioids maximized Adjuvant analgesics used Selected procedures when benefit outweighs burden CURES monitoring unless the patient is in hospice Opioid contracts and drug testing on a case-by-case basis Less attention to long term side effects

8 Treatment of chronic non-malignant pain Focus on function Goal to limit opioids maximize non-opioid analgesics Stress coping skills and non-pharmacological interventions For patients where opioids are considered appropriate Monitoring and treatment of long term side effects Standard opioid contracts Regular drug testing and CURES monitoring Periodic weaning Specific documentation requirements

9 Clinical Case 50yo man with stomach cancer and peritoneal carcinomatosis. He currently takes Norco 10/325mg PO q6hrs and Percocet 10/325mg PO q6hrs.

10 Safe ER/LA Opioid Use* Ensure patient tolerates high-enough doses of IR opioids before considering ER/LA opioids Consider REMS training Use equianalgesic dosing tables Consider ER/LA opioid dose up-titrations based on pain level, PRN usage, and side effects Opioid Morphine Oxycodone Hydromorphone Oxymorphone Brand names MS Contin (q8-12hrs), Avinza (q24hrs), Kadian (q12-24hrs) Oxycontin (q12hrs?) Exalgo (q24hrs) Opana ER (q12hrs) *ER/LA: Extended-release/Long-acting

11 Safe ER/LA Opioid Use* Ensure patient tolerates high-enough doses of IR opioids before considering ER/LA opioids Consider REMS training Use equianalgesic dosing tables Consider ER/LA opioid dose up-titrations based on pain level, PRN usage, and side effects Opioid Morphine Oxycodone Hydromorphone Oxymorphone Brand names MS Contin (q8-12hrs), Avinza (q24hrs), Kadian (q12-24hrs) Oxycontin (q12hrs?) Exalgo (q24hrs) Opana ER (q12hrs) *ER/LA: Extended-release/Long-acting

12 Equianalgesic Dosing Table Drug PO/PR (mg) IV/IM/SC (mg) Morphine Oxycodone 20 N/A Hydrocodone 30 N/A Hydromorphone There is more than one published table There are apps available but the reliability is variable Pick a table from a reliable source and use it! (APS, CDC, AAFP, etc.)

13 Calculating Oral Morphine Equivalents PO morphine equivalents are the currency of the conversion realm. Common denominator for safety and used by convention Allows quantification of opioid consumption and often a necessary step for opioid rotations Write steps of opioid rotation and double check your work

14 Incomplete Cross-tolerance Start with the published equianalgesic dose and decrease by 25-50% Consider clinical criteria to decide reduction percentage Smaller decrease if rotation is for controlled pain, larger decrease if rotation is for adverse effects

15 Clinical Case 50yo man with stomach cancer and peritoneal carcinomatosis. He currently takes Norco 10/325mg PO q6hrs and Percocet 10/325mg PO q6hrs. Which long-acting? What dose? PRN doses? Why not morphine?

16 Clinical Case Calculate total daily dose of each opioid Calculate 24hr oral morphine equivalents Reduce dose 25-50% for incomplete cross-tolerance Divide by 2 for q12hr administration of ER morphine Prescribe breakthrough IR morphine (5-15% of scheduled daily dose) Don t forget bowel regimen!

17 Clinical Case You see patient again a couple months later. He has been taking MS Contin 60mg PO q12hrs. For breakthrough pain, oral morphine solution 10mg PO q4hrs PRN. He gets admitted for significant nausea/vomiting and you re worried about gastric outlet vs. small bowel obstruction. Cannot tolerate oral meds anymore and his pain is 20/10.

18 Patient Controlled Analgesia Poorly controlled pain and dose-finding, or if anticipating rapid opioid titrations, or short-term incidental pain (e.g. post-op) If in doubt, use low basal (or no basal) and rely more on boluses PCA bolus dose is much smaller than effective RN administered PRN dose (approx % of effective dose) If giving a basal rate, PCA bolus dose is usually % of basal rate (e.g. if basal rate is 1mg/hr, PCA bolus is usually 0.5mg or 1mg) Usual lockout is 10-15min Consider keeping usual sustained-release opioid (e.g. MS Contin) instead of a basal rate

19 Clinical Case Patient is finally comfortable on the PCA He has placement of a venting g-tube and a feeding j-tube and is ready for discharge

20 Transdermal Fentanyl Patch Peak effect after application 24 hrs Patch effect lasts hrs Opioid tolerant patients only Ensure adherence to skin Rotating opioids Start 50% of equi-analgesic PO dose 6 hours after patch removed Then continue to 100% dose at 12 hours after patch removed

21 Methadone Always ask for help when considering methadone (pain management team or palliative care team) Dose interval for methadone is variable (q8h or q12h is usually adequate) Adjust methadone dose q 4-7 days WHY? (t ½ = 2 to 4 days) Opioid tolerant patients only

22 Opioid Clearance Concerns Conjugated by liver 90-95% excreted in urine Dehydration, renal failure, severe hepatic failure Increase dosing interval, decrease dose Avoid morphine in ESLD, ESRD, or rapidly failing kidney or liver function

23 Ask for help! Using opioids can be tricky, especially at the beginning If ever in doubt, feel free to as for help: Palliative care team: any cancer-related pain or any pain in patients with short prognosis. Consult line: x98532 Pain management team: all other pain syndromes. Consult line: x97483