Transcript Surgery Intern Boot Camp: Pain Management

John Wolfe, MD
Assistant Professor of Clinical Anesthesiology
Indiana University Hospital
Chronic Pain Patients
Post-op pain can be difficult to manage
in patients with chronic pain, especially if
the patient has been taking opiates at
home.
 Chronic pain is often accompanied by
anxiety, depression, and other
psychiatric conditions which complicate
care.
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Chronic Pain Patients
Managing pain control expectations preop is helpful. Make sure that your
patient understands that if their pain
score is 8/10 prior to surgery, it won’t be
1/10 after surgery.
 Help patients understand how side
effects may limit the doses of opiates
that we give them.

Preoperative Discussion
Discussion of the following with the patient:
 Precise opioid use (drug, dose, schedule).
 Anticipation of increased postoperative
pain.
 Patient’s fears and expectations related to
pain management.
 Effective management strategies after
previous procedures.
 Postoperative pain management plan.
Chronic Pain Patients
Remember that a chronic pain patient’s
vital signs are not a good indicator of
their pain level.
 The only way to determine how much
pain the patient is having is to ask…
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Opioid Tolerance
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Defined as increasing doses of opioids to
produce the same pharmacological effect.
No tolerance to miosis and constipation effects.
Tolerance depends on type of medication, route
of administration etc.
Tolerance to effects occurs at different rates.
Tolerance to analgesic effect does not imply
same level of tolerance to sedation or respiratory
depression.
Dependence implies development of withdrawal
symptoms on abrupt discontinuation.
Opiate-Tolerant Patients

Expect opiate tolerance in anyone taking:
 Hydrocodone or oxycodone > 30 mg daily
 Any amount of oral morphine or Dilaudid
 Methadone
 A fentanyl patch
 Any recreational opiates

Patients often minimize their opiate intake.
You may have to go over the patient’s
home meds several times to get an
accurate accounting.
Opiate-Tolerant PCA Dosing

Approach to dosing:
 Convert the patient’s home opiates to an
equivalent dose of IV morphine or Dilaudid.
 Dose converters are available online.
 Set the PCA so that the patient can increase
total opiate intake by 25-50% over the home
dose.
 Be prepared to increase the PCA dose.

Use non-opioid analgesics whenever
possible (ketorolac, APAP, ibuprofen).
PCA Basal Rates
Consider a PCA basal rate in any patient
who is NPO and who was taking
sustained-release opioids at home.
 Convert the sustained-release daily
dose to an IV hourly equivalent, and set
the initial basal rate for 50-75% of that
hourly dose.
 Never run a basal rate on a patient who
has sustained-release opioids or a
fentanyl patch.

Opiate-Tolerant Patients
Remember that opiate-tolerant patients
are at higher risk for respiratory
depression than opiate-naïve patients.
 Tolerance to analgesia develops more
rapidly than tolerance to respiratory
depression.
 Patients may have enough opiate on
board to be apneic, but still complain of
10/10 pain every time you wake them
up.
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Pseudoaddiction
Resembles addiction superficially.
 Behavior is a response to uncontrolled
pain.
 Once pain is treated by appropriate
measures including increased opioids,
the behavior resolves.
 Patients are often labelled as “drug
seeking”.
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Opioid-Induced Hyperalgesia
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Chronic exposure to opioids can increase
pain sensitivity in some patients.
“Rewiring” occurs at the level of the spinal
cord and brainstem.
Pain stimuli that should be minor are
perceived as severe (hyperalgesia).
Non-painful stimuli can be perceived as
pain (allodynia).
Unsurprisingly, increasing the opioid dose
is not terribly effective.
Predictors of chronic persistent
postoperative pain
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Preoperative factors
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Presence of preoperative pain.
Repeat surgery.
Psychological vulnerability (eg, neuroticism).
Work-related injury.
Surgical factors
 Type of surgical procedure (breast, thoracotomy,
inguinal hernia).
 Surgical approach with risk of nerve damage.
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Postoperative factors
 Intensity of early postoperative pain.
 Postoperative radiation therapy or chemotherapy.
Neuropathic Pain

Qualities of neuropathic pain:
 Pain may be described as “shocking” or
“electrical”.
 Pain follows a nerve distribution rather than
correlating with the surgical incisions.
 Pain is out of proportion to the incisions.
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Try starting gabapentin 600 mg bid or
tid.
 Sedation is the main side effect to watch for.
Pain Consults
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At IU Hospital, there are 3 pain services:
 Anesthesia Acute Pain: Short-duration invasive
pain procedures, like epidurals and intrathecals.
 Palliative Care (Dr. Aref): Management of
inpatient opioid tolerance, complicated pain
regimens, and general symptom management.
 Chronic Pain Clinic (Dr. Wellington and
Dorwart): Management of intrathecal pumps,
spinal cord stimulators, and outpatient
analgesics.
Pain Consults
If your patient would benefit from a
block, or has side effects from a block,
call APS (312-2787).
 If you need to know what to do with your
patient’s intrathecal morphine pump, call
the patient’s chronic pain physician.
 If you need help with figuring out an oral
pain regimen for a patient to go home
on, call Dr. Aref.
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Feel free to email me with questions or for a copy of this PowerPoint:
[email protected]