Management of patients on strong opioids.pdf

Perioperative management of
patients on strong opioids
By Addisu. M ( BSc, MSc in ACA )
For year III anesthesia students
September, 2023
Addisu.M (Bsc, Msc in ACA) 1
14-Sep-23

Case scenario
A 58-year-old man was admitted to the hospital with a non-
healing foot ulcer related to severe peripheral vascular
disease. He also had a history of chronic obstructive disease
and chronic pain.
His pain was long-standing and related to multiple prior
neck and back surgeries. For years he had been treated
with long-acting morphine (extended-release 40 mg twice
daily) as well as additional opioids for breakthrough pain.
 On admission, he reported 8/10 pain, despite receiving his
home opioid regimen. After a surgical amputation to treat
the ulcer, his pain worsened to 10/10.
What is your consideration for managing this patient???
14-Sep-23 Addisu.M (Bsc, Msc in ACA) 2

Introduction
 Strong opioids are a fundamental component of acute
and cancer pain management
 However, this class of medication is commonly taken
illicitly and have become increasingly prescribed in the
management of chronic non-malignant pain (CNMP)
 Awareness of the physiological and pharmacological
consequences of chronic opioid usage is necessary to
successfully manage this challenging patient group.
 Why ???
14-Sep-23

Cont.…
 Achieving adequate pain control in patients on chronic
opioid therapy is challenging
Patients may need higher doses (dependence)
Patients may experience great pain with less
noxious stimuli (opioid-induced hyperalgesia)
Physicians may be reluctant to prescribe higher
doses
 This can result in under-treatment of pain in this
patient population

Consequences of Strong Opioid Use
 The regular administration of strong opioids has a
psychological
physiological consequences
 The most commonly recognized side-effects of strong
opioids include nausea, constipation, sedation and
respiratory depression
 The anesthetist should be careful to question patients
about strong opioid use
14-Sep-23

Psychological Consequences
Addiction
 Addiction is defined as a primary, chronic
neurobiological disorder characterized by particular
patterns of behavior and physiological adaptation
 Behavioural alterations include impaired control over
use (e.g. unsanctioned dose escalation), compulsive
use, continued use despite causing harm and craving.
 Addiction is a major concern for both patients and
medical professionals who are considering prescribing
strong opioids.
14-Sep-23

Cont.…
Dependence
 Dependence is a neuro-pharmacological disorder
characterized by neuronal adaptation and plasticity.
 Unlike addiction, this does not necessarily involve a
behavioral component (although addiction may co-exist
with dependence).
 This will occur with a fall in plasma levels or receptor
occupancy of the relevant drug.
 Common reasons for this are abrupt withdrawal, rapid
dose tapering or administration of an antagonist.
14-Sep-23

Physiological Consequences
Tolerance
 Tolerance is commonly encountered in clinical practice
and refers to a diminished analgesic effect from a
given dose of opioid.
 Pharmacologically this represents a rightward shift in
the dose-response curve for a particular opioid i.e. a
greater dose is required to achieve the same analgesic
effect.
 different types of tolerance have been described
learned,
pharmacokinetic
pharmacodynamic.
14-Sep-23

Cont.…
Learned tolerance: This refers to a reduction in the
apparent effect of a drug due to adaptive behaviour on
the part of the patient.
Pharmacokinetic tolerance: This mechanism of
tolerance may result from altered distribution and
metabolism of the drug, typically as a result of
enzymatic induction or inhibition.
Pharmacodynamics tolerance: occur at two levels.
The first of these is desensitization of the opioid
receptor and second mechanism postulated in opioid
tolerance is the effect on the NMDA receptor.
14-Sep-23

Tolerance vs Dependence vs. Addiction
Tolerance
Over time larger doses are needed to achieve results
Opioid tolerance is likely at 60 mg of OME for ≥7 days
Dependence
Withdrawal symptoms can occur if opioid is suddenly
discontinued or excessively reduced
Addiction
Psychological dependence
a brain disease that is manifested by compulsive
substance use despite harmful consequence

Opioid Induced Hyperalgesia
 Chronic opioid administration can lead to a paradoxical
effect whereby a patient displays increased sensitivity
to painful and non-painful stimuli.
 This is thought to arise because of complicated
neurochemical changes in the CNS brought about by
expression of pro-nociceptive neuropeptides.
 This condition is typically seen after rapid dose
escalation of opioids and is characterized by
widespread, generalized pain and sensitivity
14-Sep-23

Opioid-Induced Hyperalgesia
 OIH is a type of secondary hyperalgesia. It is associated
with diffuse nociceptive sensitization due to opioid exposure
 Glutamate receptors are involved with this phenomenon
 Both short- and long-term opioid use have been shown to
increase NMDA receptor activity at the spinal level
 This increased NMDA receptor activity and subsequent
downregulation of the reception was associated with an
increased level of hyperalgesia
 Increasing the dosage of opioids only worsens the situation
and decreasing the dosage is advisable.
14-Sep-23

Cont.….
 OIH is a common side effect of opioid administration,
occurring in both acute settings and long-term
prescriptions.
 It can be challenging to diagnose, given the similarities
to several pain syndromes, and in fact, it may be one
of many factors causing pain in a postoperative
patient.
 Remifentanil has been shown to be a common
causative agent of OIH in the perioperative setting,
although many opioids can cause OIH.

Peri-operative Management
Pre-operative assessment: patients maintained
on long term opioids have far higher pain
scores and
opioid consumption post-operatively than
would be expected from simply replacing a
pre-operative opioid dose.
Perioperative management of patients taking
opioid therapy for chronic pain is very
challenging for anesthetists/anesthesiologists.
14-Sep-23

Preoperative recommendations
 Patients should be screened for chronic pain and opioid
use in the preoperative period (full biopsychosocial
assessment of pain).
 The Oral Morphine Equivalent per 24 hours (OME) of
prescribed opioids should be noted
 Prehabilitation: Consideration should be given to
reducing preoperative anxiety and catastrophising
 A perioperative management plan should be
formulated with the patient and communicated to the
surgical and anesthetic team.

Cont.…
14-Sep-23

Intraoperative Recommendations
Opioid sparing multimodal analgesia provides better
pain relief than reliance on a sole agent.
Evidence-based, procedure-specific analgesic
techniques should be used when evidence is available.
Perioperative pain management techniques must be
tailored to individual patients.
PCA: the use of a PCA in such circumstances is
generally safe

Cont.…
Opioid rotation
 Switching from one opioid to another
 The efficacy of a particular opioid decreases over a
period of time.
 The addition of another opioid at equal doses helps
restore the analgesia.
 This is based on the fact of incomplete cross tolerance
due to activation of different receptors.
14-Sep-23

Cont.…
Equianalgesia:
 Different dose of two opioids that approximately
provide the same pain relief
 morphine 10mg parenterally standard
 Reduce calculated dose by 25 – 50% when switching
to a new opioid to account for cross-tolerance

Approximate opioid equivalence

Summary
14-Sep-23

References
• ANAESTHESIA TUTORIAL OF THE WEEK 260
• A useful calculator for doing so is available at:
https://paindata.org/calculator.php
• Surgery and Opioids: Best Practice Guidelines 2021

14-Sep-23 23
Addisu.M (Bsc, Msc in ACA)

Management of patients on strong opioids.pdf

Recommended

Recommended

More Related Content

Similar to Management of patients on strong opioids.pdf

Similar to Management of patients on strong opioids.pdf (20)

More from samirich1

More from samirich1 (20)

Recently uploaded

Recently uploaded (20)

Management of patients on strong opioids.pdf