Managing Opioids

Responding to pain

Patients fear that their pain will not be well controlled. Opioid analgesics are frequently needed by palliative care patients whose pain is moderate to severe.

Key points

Persistent pain should be treated promptly
- A high index of suspicion about the presence of pain is needed in agitated patients who are unable to verbalise their experiences, due to dementia, communication problems or reduced level of consciousness.
  The Abbey pain scale (1.06MB pdf) measures pain in those who can not verbalise.
The aim is to achieve a stable regimen using a long-acting opioid, plus an as-needed short-acting opioid for the patient to use in episodes of incident or breakthrough pain.
Morphine, oxycodone or hydromorphone are appropriate opioids to use when initiating treatment.

Abbey Pain Scale (1.06MB pdf)

Transdermal patches are an option for stable pain, but due to slow onset and long duration of action are not suitable for initial titration of analgesia
- Transdermal buprenorphine is suitable for patients with stable mild pain only. A 20 mcg/hour buprenorphine transdermal patch is equivalent to 30 mg morphine daily orally
- The lowest dose available (12 mcg/hour) of fentanyl transdermal patch is equivalent to 45 mg morphine daily orally.
Some analgesics are inappropriate for use in palliative care, either because of their pharmacokinetics, potential for drug interactions, or other problems. These include:
- Pethidine
- Dextropropoxyphene (Capadex, Digesic, Paradex, Doloxene)
- Dextromoramide
- Pentazocine.
Tramadol and buprenorphine are commonly used in primary care, however they have a therapeutic ceiling which may make them less suitable for pain management in a palliative care patient.
Pain which is not responding to opioids despite titration should be reassessed, as an opioid switch may be required or the mechanism of the pain may require alternative analgesic strategies, including interventional and/or non-pharmacological approaches. Consult a specialist pain medicine physician, or palliative medicine physician.
When switching from an oral opioid to a continuous subcutaneous opioid infusion a dose conversion table can be helpful to calculate the needed change in medication. See palliAGED Symptoms and Medicines for more on this or use the Faculty of Pain Medicine ANZCA Opioid calculator.
Safe Care Victoria has developed guidance on opioid conversion for use by specialist palliative care clinicians. This includes conversion tables. they also provide the following guidance:

The Syringe driver compatibility Guidance Document (689kb pdf), Safer Care Victoria
The Palliative Sedation Guidance Document, Safer Care Victoria
The Anticipatory Medicines Guidance Document, Safer Care Victoria.

The national guidelines provide general advice about prescription drugs and driving (see section 2.2.9).

The specific advice about opioids is:

There is little direct evidence that opioid analgesics such as hydromorphone, morphine or oxycodone have direct adverse effects on driving behaviour. Cognitive performance is reduced early in treatment, largely due to their sedative effects, but neuroadaptation is rapidly established. This means that patients on a stable dose of an opioid may not have a higher risk of a crash. This includes patients on buprenorphine and methadone for their opioid dependency, providing the dose has been stabilised over some weeks and they are not abusing other impairing drugs. Driving at night may be a problem due to the persistent miotic effects of these drugs reducing peripheral vision.