Pain is what the patient says it is … but not all pain is mu-opioid responsive …
Bio-Psycho-Social-Spiritual
assume most acute pain is predominantly “bio”
assume most chronic pain has elements of “psycho-social-spiritual” + neuropathy
pain mgmt case #1
78 female severe lower extremity ulcerations – circumferential on right
diabetes, morbid obesity, s/p multiple debridements, skin graft several years ago
c/o pain – constant, prickly … “don’t kill me with that morphine”
ms elixir (20 mg/ml ‘roxanol’) 2-5 mg po q 2 hrs prn
first 36 hrs used 50 mg ms
start ms contin 15 mg po bid (basal)
continue prn roxanol (breakthrough)
General Guidelines for Opiate Administration
peak effect in 15-20’ iv, 30’ sq, 60-90’ po; 1st order kinetics
chronic pain – basal + breakthrough
acute pain – morphine dose: 2.5-10 mg SC/IM/IV q2-6h prn; Alt: 0.05-0.1 mg/kg IV load, then 0.8-10 mg/h IV; Info: consider lower dose, longer interval in elderly pts or pts <50 kg (epocrates)
start low, go slow
7-9/10 increase 50-100%; 4-6/10 increase 25-50%
frequent assess – re-assess
know opiate equivalents
risk of opiates is greatest when first begun
Opiate Equivalents
ms = hydrocodone = oxycodone
hydromorphone = 4 * ms
fentanyl patch = ½ daily po ms dose
oral/parenteral = 3/1
meperidine = 1/10 ms
methadone = ms/15 + 15
allow 25% cross tolerance
conservative basal … liberal bolus
pain mgmt case #2
31 yo male with acute severe abdominal pain
no significant pmh
right side radiating to groin/testicles
options … ?
Clinical Assessment
level of symptoms; use of breakthrough doses; pupils; resp rate; level of consciousness/arousability
clinical setting; consider n of 1 trial
Opiate Prescribing … some common concerns…
tolerance
dependence
addiction
respiratory depression
Opiate Side Effects (ADE’s)
GI – dry mouth, nausea/vomiting, constipation
Derm – pruritus
GU – urinary retention
Neuropsych – sedation, mild cognitive dysfunction
neurotoxicity – delirium, perceptual disturbances
pain mgmt case #3
72 yo lung ca with bone mets
increasingly severe hip and arm pain – constant, aching, well localized
initially controlled with 4-6 percocet 5’s/day
over past 2 weeks has used 12/day with only partial relief
options … ?
Opioid Neurotoxicity
delirium; perceptual disturbances; myoclonus (jerky movements); hyperalgesia (heightened pain level)
allodynia (pain on light touch); seizures
r/o other causes … esp meds; decrease dose; lorazepam (not anti-psych); change opiate; use other analgesic
change route (decrease metabolites)
pain mgmt case #4
67 yo male with idiopathic peripheral neuropathy
lower extremity pain moderate at rest
hx alcoholism
significantly interferes with activity (walking, golf)
significant ade’s (cns) as pregabalin titrated to max dose (600/d)
options … ?
pain mgmt case #5
58 yo with metastatic breast cancer and associated pain is well controlled on 0.8mg/hr ms with rare boluses
She is being discharged home today, gut working fine … orders for po pain mgmt?
Chronic ‘Benign’ Pain
opiate pendulum swinging back
no data opiates help in this setting
opiates might harm including OD
treat anxiety-depression (50% incidence)
adjuvants – PT – cog/behavioral …
“We do not have safe and effective treatments for your pain syndrome.”
Grady – Opioids for Chronic Pain – Archives Int Med – June 13, 2011. doi:10.1001/archinternmed.2011.213