Pain Medicine
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Transcript Pain Medicine
Antonio Quidgley-Nevares, MD
Associate Professor
Eastern Virginia Medical School
Physical Medicine & Rehabilitation
Objectives
Define pain
Review pharmacologic management options for
chronic pain
The opioid treatment agreement
Documentation and monitoring
How much opioids are consumed in the U.S.?
Opioid Statistics
USA is 4.6% of world population
USA consumes 80% of the world’s opioids
USA consumes 99% of the world’s hydrocodone
This statistic is very interesting
Why? It’s complicated
Pain Epidemiology in The United
States
1. Pain is the most common reason a person seeks care
from a physician.
2. Ninety percent of all Americans regularly
experience acute or chronic pain.
3. One third of all Americans will experience chronic
pain during their lifetime.
Pain Epidemiology in The United
States
The economic impact of pain on the healthcare
system and society is enormous.
Chronic pain accounts for 90 million physician
visits annually, 14% of all prescriptions, and more
than 50 million lost workdays per year.
Total annual healthcare costs are estimated in
excess of 100 billion dollars.
Pain Epidemiology - U.S. Estimates
CHRONIC PAIN
77.3 mil (US)
nociceptive
neuropathic
25.6 mil (US)
17.5 mil (US)
Diabetic neuropathy (DN)
post-herpetic neuralgia (PHN)
radiculopathy (RADIC)
Fibromyalgia
Osteoarthritis
rheumatoid arthritis
visceral
9.1 mil (US)
IBS
Pancreatitis
bladder pain
Non-cardiac chest pain
abdominal pain syndrome
MIXED
neuropathic and nociceptive
25.1 mil (US)
Cancer pain
Low Back pain
CRPS
Mixed agents will influence >
68.2 mil patients
What is pain?
Pain Definitions
Pain = An unpleasant sensory and emotional
experience associated with actual or potential tissue
damage, or described in terms of such damage.
International Association for the Study of Pain (IASP) – Committee on
Taxonomy 1979
Pain Definitions
In reality, pain is whatever the patient says it is.
It is always relative and highly subjective.
Pain Definitions
Acute pain = Strictly speaking, pain lasting less than 3-
6 months.
Or : Pain occurring during a period of known injury.
Pain Definitions
Chronic pain = Pain lasting more than 3-6 months.
Or : Pain lasting beyond the period of expected recovery
from an injury.
Should we treat or manage every patient that reports
pain?
“…the ethical obligation to manage
pain and relieve the patient’s
suffering is at the core of the health
care professional’s commitment”
Carr et al. US Dept of Health and Human Services
We ARE obligated to treat pain
But…
Not obligated to treat on the first visit
Not obligated to treat in the absence of adequate
diagnostic workup (physical/psychological)
Not obligated to treat with opioids
Not obligated to treat as patient specifies
Not obligated to treat using only pharmacology
Not obligated to treat without requiring patient
involvement and responsibility
Pain Assessment
Onset
Psychological
Location/Site
Aggravating
Temporal profile
Alleviating
Quality
Impact on Function
Unpleasantness
Habits
Distress
Coping Skills
Associated Symptoms
Pain Assessment
In addition to a complete history, information
regarding all prior therapeutic measures attempted is
important.
These may include: medication (by class), injections,
neurolytics, surgeries, physical/occupational therapy,
behavioral approaches, chiropractic care,
acupuncture, TENS, herbal remedies.
If something has not worked previously, ask why.
Treatment failures occur for a number of reasons,
including: failure to stay on a drug due to tolerable
side-effects, improper dosing, improperly targeted
anatomy, change in the patient’s condition, co-morbid
conditions.
Pain Assessment
Review prior work-up to assess for accuracy
and completeness.
Does anything need to be repeated?
Are prior diagnoses confirmed by the workup?
Complete as needed:
1. Imaging
2. Electrodiagnostic Evaluation
3. Nuclear Medicine
4. Chemistries
5. Consultation – Psych, Surgical, Rheum.
6. Diagnostic blocks
Pain Assessment
Complete prior:
medical/surgical/social/family/occupational
histories.
Physical Exam should be complete, but
targeted to systems of complaint. Usually this
means functional musculoskeletal and
neurological exams are dominant.
Localization of pain by region and down to
point of maximal tenderness.
The exam starts when you first see the patient.
All observational information is important.
Watch for inconsistencies
Assessment of Pain
Visual Analog Scale
Vertical or horizontal line with verbal, facial or
numerical continuum
5 years or older
Reliable and valid
Intervals on numerical scales may not be equal from a
child’s perspective
Do not compare one patient’s VAS with another patient
VAS
Treatment of Pain
Many patients come to pain center/clinics with
misconceptions and unrealistic expectations. These
should be addressed fairly early on, without alienating
the patient.
The primary goal of treatment must be based on
improving function, not on reducing pain.
Most people will increase their activity level until
they are essentially in the same level of pain.
Treatment of Pain
Pain Management centers and clinics are not able to
“cure” pain – Patients often do not understand this.
Approach pain reduction by setting realistic goals.
50% reduction of daily pain reduction represents a
major improvement.
Treatment of Pain
Use of a multidisciplinary approach is resource
intensive, therefore it must be planned and make
sense for a given patient. The plan should evolve as
the patient makes gains.
Having said this, patients should not be able to pick
and choose their most desired portions of the
program. For many this results in only passive
participation, which may be why prior attempts to
treat them have failed.
Patients must recognize the importance of being
invested in their own recovery.
Treatment of Pain
Failure to treat co-morbid medical and psychiatric
conditions makes the task of the pain center/clinic
difficult, if not impossible.
A history of addiction or drug seeking behavior should be
investigated and addressed. This type of patient may be
more appropriate for a different clinic.
Compliance with the clinic policies is very important.
Assess for addiction risk
Tools of the Pain Trade
Non invasive
Exercise
Cognitive Behavioral
Therapy
Physical and
Occupational Therapy
Chiropractic
Nutritional Therapy
Massage Therapy
Psychotherapy
Alternative/complementa
ry therapies
Invasive
Pharmacologic pain
meds
Anesthetic blocking
agents
Neuromodulatory
techniques
Surgery
Neuroablation
Treatment of Pain
1. Pharmacology – Drug Classes
A.Opiates
1. Methadone
2. Morphine, Fentanyl, Demerol, Oxycodone, Hydromorphone
3. Darvon, Ultram
B.Non-Opiates
1. Tricyclics and atypical antidepressants
2. NSAIDS – COX1, COX2
3. Steroids
4. Antiepileptics
5. Muscle relaxants
Alpha agonists
Benzodiazepines
Opioid Analgesics
Bind to mu, kappa, delta opioid receptors
Inhibit transmission of nociceptive input periphery to
spinal cord, activate descending inhibitory pathways,
alters limbic system
Opioid Analgesics
Most effective are full mu agonist - do not exhibit
ceiling effect
Avoid partial and mixed due to possible ceiling
Often cross sensitivity within a subclass but patient
may respond differently to another subclass
Opioids: Phenanthrenes
Representative drug:
Nalbuphine (Nubaine,m)
Morphine
Similar drugs:
Butorphanol (Stadol,m)
Buprenorphine (Bupronex,p)
Codeine
Hydrocodone
Oxycodone
Hydromorphone
Levorphanol
Oxymorphone
Heroin
Naloxone
p=partial agonist
m=mixed
Opioids: Benzomorphans
Representative drug: Pentazocine (Talwin, m)
Similar drugs:
Diphenoxylate (lomotil)
Loperamide
Opioids: Phenylpiperidines
Representative drug: Meperidine (Demerol)
Similar drugs:
Fentanyl
Sufentanyl
Alfentanyl
Remifentanyl
Opioids: Diphenylheptanes
Representing drug: Methadone
Similar drugs:
Propoxyphene (Darvon)
Tramadol
Partial mu agonist, serotonin and norepinephrine
reuptake inhibitor
Risk for seizures
May be helpful for neuropathic pain due to multiple
areas of action.
Tapentadol
Partial mu agonist, norepinephrine reuptake inhibitor
Schedule II opioid
May be helpful for neuropathic pain due to multiple
areas of action.
Opioid side effects
Constipation*
Respiratory depression
Drowsiness
Itching
Confusion
*most common, mu binding in GI track, no
tolerance
Non-opioids: Acetaminophen
No platelet activity, no gastric mucosa, no anti-
inflammatory effects
Similar analgesic and anti-pyretic to NSAIDs
Dose limited to 4000 mg/day – often not noticed in
combo meds
Careful with Liver and warfarin
NSAIDs
Inhibition of cycloxygenase inhibiting formation
of prostaglandin / leukotrienes -> sensitize
peripheral nerves and central sensory neurons
Have ceiling dose (increase in side effects without
additional analgesia)
Antipyretic
No physical or psychological dependence
Adjuvants
TCA, SSRI and SNRI– neuropathic pain and
concomitant depression
Block reuptake of monoaminergic neurotransmitters
(i.e. serotonin...) in CNS.
Descending pain modulatory pathways use these
neurotransmitters.
Anticonvulsants – decrease ectopic spontaneous firing
of sensory neurons associated with neuropathic pain
Adjuvants
Muscle relaxants – for relief of acute muscle injury
Soma – high potential of addiction
BNZ – acute anxiety or spasms, not analgesics
Lidoderm – neuropathic pain
Calcitonin – pain of osteosporotic fracture
Baclofen – spasm / spasticity
Capsaicin – Depletes Substance P
Mechanistic Approach to Pain Treatment
Descending inhibition
Brain
NE/5HT GABA
Opioid receptors
Peripheral sensitization
Terminal
PGEr
Na+ TTXr
NK-1
VR-1
NGF
Opioid r
NEr
PNS
Na+ TTXr
TTXs
Spinal
cord
Central sensitization
Ca++ :
NMDA:
PGE:
Subs P
Mechanistic Approach to Pain Treatment
Descending inhibition
Brain
NE/5HT GABA
Opioid receptors
TCAs
SNRIs
Opioids
Tramadol
Clonidine
Baclofen
Clonazepam
Peripheral sensitization
Terminal
PGEr
Na+ TTXr
NK-1
VR-1
NGF
Opioid r
NEr
PNS
Na+ TTXr
Spinal
cord
TTXs
NSAIDs
COX-2i
Opioids
Capsaicin
Clonidine
TCA
CBZ OXC
TPM LTG
Mexiletine
Lidocaine
Central sensitization
Ca++ : GBP; OXC Conotoxin
NMDA: Ketamine, TPM
PGE:
Dextromethorphan
Methadone
NSAIDs / COX-2
Mechanistic Approach to Pain Treatment
Descending inhibition
Disease
Modifiers
Brain
NE/5HT GABA
Opioid receptors
TCAs
SNRIs
Opioids
Tramadol
Clonidine
Baclofen
Clonazepam
Peripheral sensitization
Terminal
PGEr
Na+ TTXr
NK-1
VR-1
NGF
Opioid r
NEr
PNS
Na+ TTXr
Spinal
cord
TTXs
NSAIDs
COX-2i
Opioids
Capsaicin
Clonidine
TCA CBZ
OXC TPM
LTG
Mexiletine
Lidocaine
Central sensitization
Ca++ : GBP; OXC Conotoxin
NMDA: Ketamine, TPM
PGE:
Dextromethorphan
Methadone
NSAIDs / COX-2
Treatment of Pain
2. Physical/Occupational Therapy
(Outpatient/Inpatient/Home Health)
Bracing, orthoses
Modalities
TENS
Stabilization – active and passive
Strengthening
Biomechanical re-education
Aquatics
Home exercises
Treatment of Pain
3. Interventions
1. Epidural Steroid Injection
2. Neurolytic Procedures
3. Radio frequency vs Chemical
4. Peripheral Nerve Blocks
5. Therapeutic vs Diagnostic
6. Autonomic vs. somatic
Treatment of Pain
4. Implanted Therapeutics
a. Spinal Cord Stimulators
Indicated for chronic pain of the limb or trunk
Electrical stimulation of the dorsal columns
b. Intrathecal Pumps
Intrathecal delivery of medications
Indicated for chronic pain and spasticity not
controlled with PO meds
IT opioids are 1/300 of the PO dose
Treatment of Pain
5. Pain Psychology
Pain is not equivalent to just nociception
Treatment of Pain
Mood and Pain
Develop a trusting treatment relationship
Educate the patient and family
Monitor for treatment adherence
Multiple meds can be used
Cognitive Behavioral Therapy
Treatment of Pain
6. Homeopathic/Adjunctive
Acupuncture
Chiropractic/Osteopathic manip.
7. Weight Control and Activity
8. Education
Educate the Patient
Educate the patient and the family on the nature
and prognosis of their condition.
On the treatment
On the importance of function
On the possibility of acute exacerbations and how
to address them
Not just by popping a pill
On the importance of their active participation in
their recovery
Documentation
Proper diagnosis
Goals of treatment
Increase function
Palliative care
Increase social interactions
Proper use of medications
4 As
Activity
Analgesia
Adverse reactions
Falls? Problems driving?
Aberrant behavior
Documentation
Monitoring
Compliance of diagnostic and treatment plans
Opioid treatment agreement and consent
Outside records
Preferably from the source and not the patient
Make a copy of valid state issued ID with current
address
Monitoring
Random pill counts
Prescription monitoring programs
Urine drug screens
“I know my patients” has been disproven as a way of
monitoring
Pain Management Protocol
Familiarize with the management options
Decide what you are comfortable with
Write down the protocol
Do not deviate from the protocol
Do not wait until you are uncomfortable or reached
the limits of the protocol before referring out
Special populations
There are special populations you may feel the need to
deviate from the protocol
You must document why you are making a therapeutic
exception
Cancer pain
Hospice/Palliative care
Opioid treatment agreement and
consent form
Some patients feel they are being treated like criminals
due to the opioid treatment agreement
“The purpose of this agreement is to give you
information about the medications you will be taking
for pain management and to assure that you and your
physician/health care provider comply with all state and
federal regulations concerning the prescribing of
controlled substances.”
Brief points and examples
I am responsible for my pain medications.
I will not request or accept controlled substance
medication from any other physician or individual
There are side effects with opioid therapy
It is my responsibility to notify my physician for any side
effects that continue or are severe (i.e., sedation,
confusion).
I am also responsible for notifying my pain physician
immediately if I need to visit another physician or need to
visit an emergency room due to pain, or if I become
pregnant.
Brief points and examples
Strictly for my own use. Never be given or sold to others
because it may endanger that person’s health and is
against the law.
I should inform my physician of all medications I am
taking, including herbal remedies.
I understand that opioid prescriptions will not be mailed
Any evidence of drug hoarding, acquisition of any opioid
medication or adjunctive analgesia from other physicians
(which includes emergency rooms), uncontrolled dose
escalation or reduction, loss of prescriptions, or failure to
follow the agreement may result in termination of the
doctor/patient relationship.
Brief points and examples
Not use any illicit substances, such as cocaine,
marijuana
Not use alcohol
While physical dependence is to be expected after
long-term use of opioids, signs of addiction, abuse,
or misuse shall prompt the need for substance
dependence treatment as well as weaning and
detoxification from the opioids.
there is no improvement in my daily function or
quality of life from the controlled substance, my
opioids may be discontinued.
Brief points and examples
perform random or unannounced urine drug testing.
I agree to allow my physician to contact any health care
professional, family member, pharmacy, legal
authority, or regulatory agency to obtain or provide
information about your care or actions if the physician
feels it is necessary.
Brief points and examples
responsible for keeping my pain medications in a safe
and secure place
Refills will not be made as an “emergency”, such as on
Friday afternoon because I suddenly realize I will “run
out tomorrow”
Brief points and examples
I understand that non-compliance with the above
conditions may result in a re-evaluation of my
treatment plan and discontinuation of opioid therapy.
I may be gradually taken off these medications, or even
discharged from the clinic.
There are several good examples of opioid treatment
agreements to be found on the internet.
Thank You !
Rich the treasure, Sweet the pleasure
Sweet is pleasure after pain
For all the happiness man can gain
Is not in pleasure, but in rest from pain.
John Dryden (1631-1700)