Pain 101 - Gutwein

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Transcript Pain 101 - Gutwein

Pain 101
Andrew Gutwein, MD, FACP
Overview
Today we will cover: 1. Pain Med Myths
2. Basics
3. Conversions
4. Starting Meds and Titrating
5. Miscellaneous
We will not cover:
1. PCA Pump
2. Injections and Spinal Meds
3. Specific Diseases (ex: Fibromyalgia)
Pain Med Myths
1. SOO: Demerol vs. Morphine
2. Respiratory Arrest
3. Addiction
4. Physician Oversight & Regulations
Sphincter Of Oddi
We are not rabbits damnit!
Respiratory Arrest
You must first:
relive pain
before you will
cause sedation
before you will
cause respiratory depression
before you will
kill someone.
Addiction
Tolerance: the need to increase a drug to achieve the same effect.
In clinical practice, significant opioid tolerance is uncommon.
Tolerance may be present in the pain patient or the addict; by
itself it is not diagnostic of addiction.
Physical Dependence: development of a withdrawal reaction
syndrome when a drug is suddenly discontinued or an antagonist
is administered. Many patients on chronic opioids become
physically dependent; its presence cannot be used to differentiate
the pain patient from the addict.
Psychological Dependence (Addiction): overwhelming
involvement with the acquisition and use of a drug, characterized
by: loss of control and use despite harm. Data suggests that
opioids used to treat pain rarely lead to psychological
dependence.
Addiction Vs. Pseudo-Addiction
Addiction Assessment
• Loss of control of drug use (has no partially filled med bottles; will not bring
in bottles for verification)
• Adverse life consequences -Use despite harm (legal, work, social, family)
• Indications of drug seeking behavior (reports lost/stolen meds, requests for
high-street value meds)
• Drug taking reliability (frequently takes extra doses, does not use meds as
prescribed)
• Abuse of other drugs (current/past abuse of prescription or street drugs)
• Contact with drug culture (family or friends with substance abuse disorder)
• Cooperation with treatment plan (does not follow-up with referrals, or use of
non-drug treatments)
Physician Oversight & Regulation
• Recent lawsuit for under-treatment of pain.
• The climate has changed! Government agencies are now more
interested in making sure pain is treated, but properly and
safely. Include in your records the pain Hx, how function
is affected, response to Rx, and improvement in function.
• Use a pain contract and write on the prescription “X opioid.…
for pain.”
• Methadone can be prescribed by office physicians for pain not
just in accredited methadone maintenance programs.
The Mild Narcs
Codeine - Mainly used in combination with tylenol as Tylenol #3
(30mg) or 4 (60mg). Used as 1-2 tabs PO q4 PRN. 10% of
people lack the enzyme needed to make it active.
Propoxyphene – 32, 65mg (1/2-1/3 as strong as codeine). Available
also with tylenol as darvocet (various doses). Used as 1-2
tabs PO q4-6 PRN (depending on preparation).
Tramadol – Ultram 50mg (max: 2 tabs PO 4xd). Ultram ER 100,
200, 300mg. maximum dose of 400mg/d. Also available in
combination with tylenol as ultracet. About as strong as
Tylenol #3. Expensive!
Hydrocodone - stronger than codeine and only used in combination
with tylenol as vicodin/ lortab or with ibuprofen as
vicoprofen. Many different preparations - dose so that tylenol
component is not toxic.
The Heavy Narcs
Morphine – {careful in severe renal insufficiency}MSIR 15,
30mg (immediate release for 4 hours), MS ER 15, 30,
60, 100mg (MSContin - long acting for 8-12 hours),
Kadian 10, 20, 30, 50, 60, 80, 100, 200mg (twice a day
preparation), Avinza 30, 60, 90, 120mg (new once a day
preparation with a maximum dose of 1600mg/d
[renal
toxicity], can be opened and spread on food)
Hydromorphone - Dilaudid 1, 2, 4, 8mg only comes as short
acting q4h (except in Canada).
Oxycodone - available alone in 5/15/30mg tabs or in
combination with tylenol as percocet (and other names
from other companies) or with ASA as percodan.
Available as Oxycodone ER (Oxycontin) 10, 15, 20, 30,
40, 60, 80mg q8-12h
The Heavy Narcs
Fentanyl - comes as 12.5, 25, 50, 75, or 100 transdermal patch
q48-72 hours. Also comes as Actiq transmucosal
lozenge for breakthrough pain 200, 400, 600, 800,
1200, 1600mcg 4xd PRN. Also available as Fentora an
acute release buccal mucosa droplet – 100, 200, 400,
600, 800mcg
Methadone – comes as 5, 10, 40mg tablets. can be used q6-8
hours for chronic pain. Write on the script “for pain”
otherwise beware the DEA. May need dose reduction
after 2-5 days of use. Watch for QT prolongation and
Torsades. No metabolites – good for CKD.
Oxymorphone – now available again! (as Opana 5,10mg and
Opana ER 5,10,20,40mg)
Basics
• Pain scale of 0-10, “0 is no pain and 10 is the pain you feel when
you’ve been hit by a truck and you are about to die”
• Chronic pain does not wear the same face as acute pain. The
patient may not look like they are in pain.
• Accept the patients’ subjective report of pain - do not start from the
position of disbelief
• Acetaminophen: 650mg q4o for fever vs.1000mg 4xd (or 1350mg
TID) for pain. Remember to be careful with patients that take
alcohol or isoniazid, zidovudine or barbiturates.
• NSAID’s are all equally efficacious at equivalent doses. High doses,
elderly patients, prolonged use, previous PUD, excessive
alcohol intake make GIB more likely.
Basics
• Ketorolac is the only injectable NSAID for up to 5 days. It is
comparable to moderate dose morphine.
• Add Tylenol or NSAID’s or both to augment narcotics.
• All narcotics are now written on the same kind of script as other
drugs. You can give out more than one months worth for
schedule 3 narcotics and you can give out 3 months worth
of schedule 2 narcotics if there is a proper chronic
indication written on the script.
• Demerol is the most emetogenic of the narcotics and its’
breakdown products can increase the risk of seizure. Do not
use in chronic pain patients! (Also it really only relieves pain
for 1-2 hours so don’t bother using it for the acute pain
patients either.)
Basics
• Morphine, oxycodone (short acting) are q3o if SQ, IV or IM and
q4o if PO.
• When converting between pain meds start the new med at 1/2 to
2/3 of the total dose of the original med because of
incomplete cross tolerance.
• There is no ceiling dose of narcotic. Use however much you need
to relieve pain. Be careful of combined pills that have
acetaminophen as that ingredient will define the ceiling
dosage.
• Always start patients on anti-constipation meds at the same time
you start narcotics! Do not fall behind. Colace is not enough
use senna or bisacodyl daily to BID too. Add sorbitol or
lactulose for refractory cases.
Conversions
Drug
morphine
oxycodone
oxymorphone
hydrocodone
hydromorphone
codeine
meperidine
methadone
heroin*
fentanyl
PO/PR
SQ/IM/IV
30
20
10
30
7.5
200
300
20(A)3-5(C)
60
NA
10
15
NA
1.5
130
75
10
5
0.1
1 percocet = 2.5mg of morphine SQ
*not recommended for patient use
Conversions
fentanyl mcg/hr
25
50
75
100
125
150
175
200
225
250
275
300
morphine mg/24hr PO
45-134
135-224
225-314
315-404
405-494
495-584
585-674
675-764
765-854
855-944
945-1034
1035-1124
Starting Meds and Titrating
• Start morphine 5-10mg SQ q3o (or 15-30mg PO) in narcotic naive
healthy pt.
• Double this baseline dosage if no effect in 30-60 min.
• Also order breakthrough pain meds. Use about 1/4 of the baseline
dosage. If using morphine 30mg PO q4o, then the
breakthrough order is morphine elixir (pills only come in
15/30) 8mg PO q1o.
• To switch to Morphine ER total the 24 hour morphine dose and
give 1/2 q12o (or 1/3 q8o for those in whom the effect wears
off after 8 hours).
• Remember to add Tylenol for added effect.
• If changing to Fentanyl patch, remember it has a delayed onset of
12 hours and 14-24 hours of residual action once removed.
Starting Meds and Titrating
• On the outpatient side, when a patient is on a long acting
preparation (usually of morphine, oxycodone or fentanyl)
remember to give them something for breakthrough pain!
• One can use tylenol #3/4, vicodin/lortab, percocet, MSIR, actiq
transmucosal for breakthrough. Use about 10% of the long
acting dose.
• At every visit remember to find out how much breakthrough they
needed so you can add that back into the long acting
preparation so they are less likely to need breakthrough next
time.
Miscellaneous
• For elderly consider hydromorphone and oxycodone as they have
no active metabolites and thus you do not need to worry
about liver/renal function.
• Be careful in renal insufficiency with morphine, tramadol and
propoxyphene as they can accumulate toxic metabolites
and cause agitation and confusion.
• For persons on Xmg of MScontin q12o who come in unable to
take PO, you can use 1/3(2X) IV over 24o.
• Radiation therapy, injectable radionuclides and bisphosphonates
can be used to help bone pain (mets).
• TCA’s, Duloxetine, Venlafaxine, corticosteroids and antiepileptics (neurontin, pregabalin, carbamazepine,
phenytoin, topiramate, depakote, lamictal) can be used for
neuropathic pain in certain situations.
Miscellaneous
• Lidocaine patch can be used for post-herpetic neuralgia.
• Topical - capsaicin cream (zostrix) can be used for neuropathic
pain and OA – lidocaine/prilocaine (EMLA) for cutaneous
anesthesia
• Clonidine patch (catapres) can be used for sympathetically
maintained pain.
• Dexamethasone 16-100mg/d in divided doses can reduce
vasogenic edema in cord compression.
• Dextroamphetamine and methylphenidate 2.5-5.0 mg at
breakfast and lunch can decrease opioid sedation. modafinil
(used for narcolepsy) can do this as well.
• If you need to use naloxone, use it diluted in 10cc, 1 cc at a time. If
you completely reverse, the person will go through withdrawal.
Fin