Lecture created by: Lindsay Nicholson, MD University of Michigan Internal Medicine

Lecture created by:
Lindsay Nicholson, MD
University of Michigan Internal Medicine
Resident Education Committee
2010-2011
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Pain: an unpleasant feeling conveyed to the
brain by sensory neurons
◦ Signals actual or potential injury to the body
◦ Also includes perception/subjective interpretation
of the discomfort
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Location
Intensity
Character
Emotional response
Pain of any type is the most common reason
patients seek medical attention
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This presentation will discuss management of
acute pain.
Chronic pain is different from acute pain.
◦ It requires comprehensive physical, functional,
behavioral and psychosocial assessment and is
beyond the scope of this presentation.
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Mr. Wilson
78-year-old man
PMHx:
◦ HTN, HPL
◦ DM2
◦ Prostate cancer w/ mets to spine and pelvis,
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HPI: Comes to the ED w/ 2 weeks of
worsening low back pain
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Metastatic cancer
Pathologic/compression fracture
Musculoskeletal strain
Bulging/herniated disk
Degenerative joint disease
Nephrolithiasis
Pyelonephritis
Psoas abcess
Retroperitoneal hematoma
Pulmonary: PNA, PE, etc.
Cardiovascular: Aortic dissection, angina equivalent
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Take a thorough Hx:
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Location and radiation
Timing, duration, onset
Severity
Character/description of the pain
Alleviating factors
Exacerbating factors
Associated Sxs
Perform a good PEx (with neuro exam)
Plain films of the lumbar spine
 What would you be looking for with plain films?
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Cross-sectional imaging?
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Chronic LBP
 Well-controlled prior to this episode w/ APAP,
ibuprofen, and occasional Vicodin
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Acute-on-chronic lumbar pain, non-radiating
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Began 2 weeks ago, getting progressively worse
Dull, achy
Rates 8/10
Alleviated by lying down, Vicodin
 Over past 2 days taking up to 8 Vicodin tab/day w/o
lasting relief
 Exacerbated by standing, walking
 No numbness, tingling, weakness, bowel/bladder
Sxs
 No inciting trauma or injury
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T 36.5, HR 80, BP 130/85, RR 12, SpO2 98% RA
Gen: Well-appearing. NAD when lying flat,
moderate distress when asked to sit and stand
HEENT, CV, Pulm, Abd exams all WNL
Point tenderness @ L3, no paraspinal or CVAT, no
flank ecchymoses
Flexion, extension, twisting all limited 2/2 pain
BLE strength 5/5 and symmetric, sensation to
light touch intact over BLE and perineum,
patellar/Achilles reflexes 2+, rectal tone WNL
Gait, heel, and toe walk WNL
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Metastatic cancer
Pathologic/compression fracture
Musculoskeletal strain
Bulging/herniated disk - no radiculopathy or cord
compression findings on PEx
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Degenerative joint disease
Nephrolithiasis
Pyelonephritis
Psoas abcess
Retroperitoneal hematoma
Pulmonary: PNA, PE, etc.
Cardiovascular: Aortic dissection, angina equivalent
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What do you want to do for Mr. Wilson?
What do you need to order?
Any special considerations for Mr. Wilson in
the first 12 hours (e.g., overnight while on
call)?
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Medical Tx:
◦ Goal is first to control pain, using IV meds if
necessary, then transition to regimen that may be
taken as outpatient (e.g., PO, transdermal)
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Surgical Tx:
◦ Is the pain fixable with surgery? (e.g., acute
abdomen, abcess/hematoma, orthopedic issues)
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Monitoring response to Tx:
◦ Does pt express relief?
◦ Does pt look comfortable?
◦ Do VS support this? (e.g., no further
tachycardia/hypertension/tachypnea)
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Subjective:
◦ Ask pt to qualify and quantify pain:
 ―Pain score‖ 1-10 scale
Objective:
◦ VS: tachycardia, hypertension, tachypnea
◦ FLACC scale
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Acetaminophen (Tylenol):
◦ Dose: 325-650mg PO Q4-6H PRN or scheduled
◦ Daily max 4000mg/day (2000mg/day in cirrhotics)
 Keep in mind when using opiate/APAP combinations
 APAP also seen in many OTC cold preparations
◦ Few side effects (unless overdosed)
◦ Effective adjunct therapy to other classes of meds
◦ Effective antipyretic
 Beware of masking fever with scheduled dosing
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NSAIDS:
◦ Ibuprofen 400-800mg PO Q4-8H PRN or scheduled
◦ Naproxen 375-500mg PO BID PRN or scheduled
◦ Many others (diclofenac, etodolac, piroxicam,
indomethacin, nabumetone, etc.)
 Gastritis, PUD
 Especially with long-term use: consider PPI
 Platelet inhibition: Don’t use if bleeding
 Worsened HTN
◦ Ketorolac (Toradol) 15-30mg PO/IM/IV Q6H PRN
 Potent NSAID, especially effective for
nephrolithiasis/ureteral colic
 Max use 5 days, inpatient use only
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Opiates
◦ Centrally-acting µ-receptor agonists
 Produce analgesia and respiratory depression by
decreasing brainstem response to carbon dioxide and
electrical stimulation
 Decrease gastric, biliary and pancreatic secretion,
induce peripheral vasodilation and promote
hypotension due to histamine release
◦ Can be very effective for management of acute pain
◦ Side effects: Respiratory depression, CNS sedation,
hypotension, constipation, N/V, pruritis
 Use with caution!
◦ Can also be habit-forming with potential for abuse
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Codeine/APAP:
◦ Tylenol #3 30/300mg 1-2 tab Q4H PRN
 Compounded with guaifenesin (Robitussin AC) for
cough suppression
 Nausea/vomiting are common side effects
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Propoxyphene/APAP (Darvocet)
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Removed from market (no more efficacious than APAP alone)
Hydrocodone/APAP
◦ Norco: 5/325, 7.5/325, 10/325 mg 1-2 tab Q4H PRN
◦ Vicodin: 5/500, 7.5/750, 10/660 mg 1-2 tab Q4H
PRN
◦ Lortab: 10/500 mg 1 tab Q4H PRN
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All PO, short-acting, for short-term use
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Oxycodone:
◦ Oxycodone 5-10mg Q4H PRN
◦ Oxycodone/APAP (Percocet) 2.5/325, 5/325,
7.5/325, 7.5/500, 10/325, 10/650 mg PO Q4-6H
PRN
 Short-acting preparations, for short-term use
◦ Oxycodone ER (OxyContin) 10-80mg PO BID
 Long-acting alternative for pts intolerant to morphine
 Higher risk for abuse/diversion
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Morphine sulfate
◦ Tablets: 10, 15, 30 mg PO Q4H PRN
◦ Liquid (Roxanol): various concentrations (useful
for pts with swallowing difficulties)
◦ Injection: 2-10 mg IV/SC Q4H PRN (may be used
more frequently with caution)
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Morphine ER
◦ MS Contin 15-30mg PO BID
◦ Kadian 30-60 mg PO daily
Morphine is especially useful for relieving
sensation of breathlessness/air hunger in comfort
care/end-of-life scenarios
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Hydromorphone (Dilaudid)
◦ Tablets: 1-4 mg PO Q4H PRN
◦ Injection: 0.1-0.4 mg IV Q4H PRN
 Note higher potency and conversion between PO/IV
 Fewer side effects (pruritis, nausea) than morphine or
oxycodone
 No long-acting formulation, should only be used
short-term
 Higher abuse/diversion potential
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Fentanyl
◦ Injection: 50-100 mcg Q30-60min PRN
 Short acting, commonly used in OR and ICU
◦ Transdermal patch (Duragesic) 12.5 – 100 mcg/hr
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Change every 72 hours
Variable absorption depending on adiposity
For use in chronic/terminal pain
Caution pts against applying heat over patch –
increased medication delivery can be fatal
◦ Transmucosal/buccal lozenges also available for
breakthrough (terminal) pain
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Methadone 2.5-30mg PO BID-TID
Buprenorphine (Suboxone, Subutex) 2/0.5mg
PO TID
◦ Long-acting opiates effective for chronic pain,
hyperalgesia, and addiction
◦ Should only be initiated/titrated under the guidance
of a pain management specialist
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Meperidine (Demerol)
◦ Short-acting parenteral opiate analgesic
◦ Removed from UM formulary as metabolite
(normeperidine) is CNS-toxic and can cause Szs
◦ Restricted to short-term use for intractable rigors
and post-op shivering
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Gives pt some control over pain relief
On average, pts use fewer milligrams/24 hours
than traditional nurse-administered pain meds
Indications:
◦ Severe, acute pain requiring frequent dosing of IV opiates
◦ Anticipate need >24 hours
◦ Pt able to understand and use button (only pt may push)
Dosing:
◦ Morphine or Hydromorphone
◦ Demand dose depends on level of tolerance, Q6-10min
◦ +/- basal (continuous) rate
◦ Stop all other opiates
◦ See guidelines for more details
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Tx: Naloxone (Narcan)
◦ For suspected opiate overdose (somnolence,
respiratory depression)
◦ 0.4 mg IV push every 2-3 min until response
 If no response after 2 doses, the Sxs are probably not
due to opiate overdose
◦ Effects are short-acting, may require repeat dosing
until opiate is cleared
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Dose with caution, especially in renal/hepatic
impairment and elderly
◦ Can always give more, but can’t take away
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Watch carefully for CNS and respiratory
depression, hypotension
Do not prescribe opiates without a bowel
regimen!
Anticipate need for antiemetics, antipruritics
◦ Avoid diphenhydramine in elderly or those at risk
for delirium
◦ Dose diphenhydramine through oral route only
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Docusate (Colace) 100mg PO BID
◦ Weak stool softener
Senna 2 tab daily-BID
◦ Weak stimulant laxative
Bisacodyl (Dulcolax) 10 mg PO or PR (suppository) PRN
◦ Stronger stimulant laxative if above fails
Polyethylene glycol (Miralax) or psyllium fiber
◦ Osmotic laxatives, non-absorbed, good for daily use
Lactulose, Sorbitol, Mag Citrate, Mineral Oil
◦ Stronger osmotic laxatives if above fail
Enemas: tap H2O, milk and molasses, SMOG (sorbitol,
mineral oil, glycerin)
◦ Avoid: Na-phosphate (lyte disturbances) and soap
suds (chemical colitis)
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Other:
◦ Tramadol (Ultram) 50-100mg PO Q6H PRN
 Weak opioid that also weakly inhibits reuptake of
norepinephrine and serotonin
 Same side effects as other opioids; potential for
dependence
 Can lower seizure threshold with SSRIs
 Also risk of serotonin syndrome
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Topical/Local:
◦ Transdermal lidocaine patch on 12H, off 12H
◦ Capsaicin Cream
 Ideal for discrete pain (i.e. postherpetic neuralgia)
 Few side effects, potential for skin irritation
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Adjunct Tx for chronic pain
◦ Require sustained use for effect
◦ Antidepressants:
 TCAs, SSRIs, SNRIs
 Effective in central pain syndromes, fibromyalgia,
neuropathic pain (esp. TCAs)
 Depression is common in chronic pain patients
 Counseling may also be helpful
◦ Anticonvulsants:
 Gabapentin, pregabalin (for neuropathic pain)
 Lamotrigine (for trigeminal neuralgia)
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Positioning
Massage
Physical therapy
Heat
Ice
Orthotics (splints, slings, compressive wraps)
Guided relaxation and biofeedback
techniques
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Inpatient goals:
◦ Pain controlled on oral or transdermal meds
◦ Able to walk, eat, void, stool
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Always think about bowel regimen
If acute pain, plan for tapering off meds once
episode has passed
If chronic pain, plan for follow-up
If terminal pain, anticipate need for escalation
◦ Palliative care/hospice?
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If orthopedic/musculoskeletal pain, could pt
benefit from physical therapy?
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Physicians VASTLY underestimate the amount of
opioid diversion by their patients
Some of your patients WILL be either selling their
meds or will pass on to family members and
friends
Opioids are rarely appropriate chronic pain—you
only create dependency and a new illness
◦ Terminal illness (esp. cancer pain) is a notable exception
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When discharging patients, the plan should be for
SHORT-TERM use
The street value of opioids is higher when using
brand names  ALWAYS prescribe using generic
(e.g., hydrocodone/APAP instead of Vicodin)
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In the hospital, Mr. Wilson was treated with IV
morphine for his L3 compression fracture
with good relief of his acute pain
Oncology was consulted, and felt there was
no further role for chemotherapy or radiation
for his metastatic prostate cancer
Orthopedics was consulted, and felt there
was no role for operative management in the
absence of spinal cord or nerve root
compression
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IR performed a kyphoplasty (injection of
cement under fluoroscopy) to stabilize the L3
vertebral body
Mr. Wilson was transitioned to long-acting PO
morphine, with short-acting PO morphine for
breakthrough
◦ Long-term treatment of his terminal pain
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Good relief of Sxs
Able to walk and perform ADLs
Daily BMs on a bowel regimen
Discharged home!
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CareLink has an Acute Pain Management
order set:
◦ Find under UH/CVC Acute Pain Management
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Find and Tx the cause of pain
Many classes of pain medications are
available for Tx of acute pain
Prescribe opiates with caution
◦ Don’t forget the bowel regimen!
◦ GENERIC NAMES ONLY!!!
◦ Plan should be for short-term use unless terminal
pain
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Consult guidelines and seek expert
consultation for treatment of chronic pain
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Pain Management in the Hospitalized Patient,
Med Clin NA, 2008
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UMHS Analgesic Prescribing Guidelines:
http://www.med.umich.edu/i/pain/Website/6
2-11-003.pdf
UMHS Guidelines for Management of Chronic
Non-Terminal Pain:
http://www.med.umich.edu/1info/fhp/practi
ceguides/pain.html
Equianalgesic Dosing Card:
http://www.med.umich.edu/i/pain/pdf%20fil
es/paincard100405.pdf