CHRONIC PAIN MANAGEMENT

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CHRONIC PAIN MANAGEMENT
Jeanette Tetrault, M.D.
WEEK 23
Learning Objectives:
1. Be able to initiate and maintain opioid therapy for pain management
2. Recall clinically-relevant pharmacology in relationship to opioid treatment
3. Establish an approach to the treatment of chronic pain with opioid drug therapy
using dose-escalation techniques
4. Summarize the arguments for and against opioid therapy in the treatment of
chronic pain
5. Distinguish between dependence, tolerance, addiction, and pseudo-addiction
Author’s Note:
I have decided to focus primarily on opioid treatment of chronic pain, as this is a
particularly nebulous area for most primary care providers. This module may be used as a
springboard for discussion of non-opioid forms of analgesia and non-pharmacologic
approaches to chronic pain management.
CASE ONE:
Mr. White is a 42-year-old gentleman who comes to your office with a chief
complaint of low back pain. (He used to see Mr. Brown, the PA in your office who
has since changed jobs.) He states that the pain has been a problem for him for “as
long as I can remember.” Upon further questioning he reports that several years
ago he was doing an “under the table job with some buddies, and I threw my back
out. I have never been the same since.” He states that he has been to multiple
providers, including Mr. Brown, to try to get to the bottom of this but feels that he
has never truly had relief from the pain. He cannot localize pain in any particular
region in his back and states that it is “all over the lower part.” He denies any
weight loss; in fact, he may have gained weight. On exam, his gait is normal
although he appears to tighten up with movement. Straight leg test elicits pain at 30
degrees without any shooting sensation down the extremity. You review Mr. White’s
chart and note that he has tried all of the following treatment modalities: NSAIDs
and benzodiazepines initially, physical therapy, ultram, acetaminophen, and
valdecoxib. He had an MRI last year that showed degenerative disease and
herniated L4-L5 disk without nerve impingement. His pain has not changed in
quality since that time.
Questions:
1. What is your initial therapeutic approach to this patient? What else do you
need to know about this patient and how will you negotiate therapy with
him?
This patient may be a good candidate to initiate opioid-based therapy for the
treatment of chronic pain. Initiating opioid therapy for chronic pain management
should be a decision made by both the physician and the patient. The patient will
benefit from knowing what side effects to watch out for and what will be expected
of him to maintain a comfortable physician-patient relationship. It is important to
make sure that the following points are distinctly highlighted by the residents:
(see Figure 2. in the article)
 Confirm the inadequacy of all prior treatments.
 Establish a diagnosis.
 Assess previous substance use/abuse history. It is important here to
discuss with the group that patients with prior substance use/abuse history
should not be automatically denied treatment. In fact, these patients may
even require increased initial starting doses of opioids given the previous
exposure. It is important to note that patients with previous drug or
alcohol abuse are at increased risk to become addicted to prescription
narcotics. Therefore, these patients need to be followed closely.
 Screen for depression. If positive, alternative treatment options may help.
 Ensure the balance of treatment benefit outweighs potential risk.
 Establish FIRM treatment goals.
 Request narcotic contract to be signed.
 Initially set up weekly appointments to assess pain control and increase
dose if necessary.
 Make sure that the patient is aware that he must come for monthly
appointments to assess pain control and to pick up prescriptions.
The initial approach should include a short-acting opioid dosed at the proper
frequency. Have the patient keep a diary of when he is taking his medication and
when he is having pain. At subsequent visits, increase the dose of his medications
until an analgesic effect is attained. Remember, combination medications are
more difficult to dose-escalate. If necessary, a long-acting opioid can be added
and the short acting medication can be reserved for breakthrough pain only.
Table 1 in the article shows dose equivalent opiate formulations that residents
can choose from. Make sure to remind residents that OxyContin® should be
avoided in any patient with whom you are concerned about diversion.
2. What potential side effects of this treatment do you want to make sure that
you discuss with the patient?
Initial side effects of constipation and nausea usually subside within a few days to
a few weeks of treatment. The patient needs to understand the potential
seriousness of personally changing dose amounts, not keeping track of medicines,
and diversion. Other possible side effects that should be conveyed to the patient
are the following: decreased libido, aggression, and possible galactorrhea. The
physician should also keep in mind that studies have shown altered immune cell
function in patients with chronic opioid use. The patient should also be educated
on the possibilities of tolerance and withdrawal if medications are stopped
abruptly.
CASE ONE CONTINUED:
Two months later, Mr. White returns for all his visits without issue. He states that
this is the best that he has ever felt, and he feels like he has gotten his family back.
He is so pleased that he is able to go to the playground with his children and not
snap at them as a result of pain. Mr. Brown calls you on the phone to check up on
his patients. You state that you have been seeing Mr. White and that he is doing well
on opioid treatment. Mr. Brown responds, “Wow, you are brave. I was sure that
guy was a ‘drug-seeker,’ I never would have given him narcotics.”
3. What is your response to Mr. Brown? Describe the different sides of the
opioid treatment for chronic pain argument. Use specific examples from your
practice.
The residents can either speak anecdotally or role-play this exercise; whatever is
more comfortable in the group that you are leading. The article outlines specific
points on both sides of the argument. The following points should be made in the
discussion:
Those points which argue for opioid therapy for treatment of chronic pain:

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Effective analgesia
Well tolerated
Proven efficacy in cancer pain, often used as a model of chronic pain
Low addiction risk if patient understands the narcotic contract, role of
tolerance, and is on the proper dose and frequency
Those points which argue against opioid therapy for treatment of chronic pain:

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

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Unproven efficacy in non-cancer pain
Encourages opiate centered lifestyle: burden is placed on the patient of
close follow-up, etc
Addiction risk/potential not entirely clear
Need for many resources that may not be available (i.e. time, personnel,
frequent appointments)
Difficult to define a ceiling dose
Difficult to balance patient analgesia while avoiding side effects
The bottom line here is that each patient should be treated as an individual. As
long as both the patient and physician are educated on the pharmacology of the
medications and understand both the positive and negative effects of treatment,
this class of medications is a good option for the treatment of chronic pain in the
right setting.
CASE TWO:
You see on your schedule that you are seeing a patient for one of your colleagues,
the APRN in the office, Mr. Blonde. Mr. Pink is a 44-year-old male with a complaint
of L hip pain. Three years ago, he fell off a ladder in a warehouse, suffering a left
femoral neck fracture requiring total hip arthroplasty. Since then, his hip pain
persists. He comes in today with worsening pain. He describes the pain as deep and
stabbing. He is currently on morphine CR (Oxycontin®) and hydrocodone
(Vicodin®). History reveals that he is a former carpenter on disability, who denies
tobacco, alcohol or illicit drugs. On exam, his gait is slow despite walking with a
cane. Vitals are normal. He is 5’11” and weighs 275 lbs. Cardiac, pulmonary, and
abdominal exams are normal. His left hip exam shows a scar, and he is clearly
uncomfortable when moving the hip through passive range of motion. In reviewing
his chart, you note that his hip X-ray from last week showed only post surgical
changes. Mr. Pink and his wife explain to you that they are very frustrated with
their provider, Mr. Blonde. Mr. Blonde feels that the patient should no longer be in
pain and wants to taper him off of opioids. However, Mr. Pink feels that he, in fact,
needs more medication to take care of his pain.
4. Why do you think Mr. Pink is experiencing increased pain?
The possibilities are as follows: (Note: Addiction and pseudo-addiction are
behavioral phenomenon, and tolerance and dependency are biologic
phenomenon).
 He is addicted to the medication. Addiction is characterized by one or
more of the following: loss of control with medication use, compulsive
medication use or continued use despite harm.
 This represents the phenomenon of pseudo-addiction. Patients with severe
unrelieved pain become intensely focused on getting relief. The intensity
with which the patient seeks relief may mimic addiction. The behavior
should resolve when the pain is adequately treated.
 Note the following statistics: (Obtained from CRIT lecture series by Dr.
Daniel Alford, July 2004) Portenoy et al, Journal of Pain Symptom
Management 1996 showed the following addiction risk:
- 0 out of 10,000 burn patients, 3 out of 2369 patients with
headache, and 4 out of 11,882 hospitalized patients receiving
intravenous pain medication without a history of prior substance
abuse.
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However, in a study in JGIM in 2002 Reid et al. studied 98 patients with
chronic non-cancer pain on opioid treatment for greater than six months
seen in a primary care clinic (West Haven VA or Yale Primary Care
Center). Of the patients studied, up to 44% were receiving opioid therapy
for the treatment of chronic back pain and the mean duration of pain as 10
yrs (1-50 years). In this series, 24% of those at the VA clinic exhibited
opioid abuse behaviors compared to 31% of those patients at the PCC.
Independent risk factors for opioid abuse behaviors were younger age and
lifetime history of substance abuse.
The patient may have tolerance to the medication. Tolerance is the need for
increasing doses to maintain the same analgesic dose.
The patient may now have dependence on the opioid medications.
Dependence is when signs and symptoms of withdrawal occur if opioids are
abruptly stopped.
CASE TWO CONTINUED:
After further inquiry, Mr. Pink admits that he has more pain as the day goes on. He
admits that he recently just started to feel better and has attempted to go to physical
therapy as prescribed. He went three times last week and once this week and has
found that his pain has become progressively worse over this time period.
5. What is the most likely cause for his increasing pain, and how will you treat
him?
Most likely, Mr. Pink is having increased pain as a result of his sudden increase
in activity. Therefore, he has increased need for pain medications. The best thing
would be to increase the dose of his long-acting medication.
References:
1. Ballantyne, JC et al. Opioid Therapy for Chronic Pain. New England Journal of
Medicine. 2003;349(20):1943-1953.
Additional References:
1. Portenoy, RK. Opioid therapy for chronic nonmalignant pain: a review of the
critical issues. Journal of Pain & Symptom Management. 1996;11(4):203-17.
2. Reid, MC et al. Use of opioid medications for chronic noncancer pain syndromes
in primary care. Journal of General Internal Medicine. 2002;17(3):173-9.
3. Alford, DP. Prescription Drug Abuse. Chief Resident Immersion Training Course
Materials. May 2004.
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