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NICE Clinical Guideline 140: Palliative care for adults: strong opioids for pain relief
Refer to the Specialist Palliative Care Team if the pain is not improving.
NSAIDs have a valuable role in palliative care for many pains. Consider NSAIDs for bone pain, liver pain, soft tissue infiltration, and inflammatory pain.
Use NSAIDs with caution if a history of peptic ulceration, cardiovascular and renal impairment, clotting difficulties or asthma. It is generally advisable to consider using a PPI if risk of GI side effects.
Other NSAIDs may be considered if the above choices are ineffective.
Please refer to section 10.1.1 for further information on NSAID prescribing.
Tramadol and buprenorphine are rarely used in palliative medicine, but patients may present to your care on them. If this is the case, continue and, in the event that they need to be altered – seek advice.
*Note: conversions are approximate and vary between individuals
Stop any step 2 opioid. If step 2 is omitted the starting dose of strong opioids should be lower and titrated upwards as necessary.
Please refer to NICE Clinical Guideline 140: Opioids in palliative care: safe and effective prescribing of strong opioids for pain in palliative care of adults (May 2012)
Seek advice from the palliative care team if the pain is severe and not responding to treatment, or if the patient reports episodes of acute severe pain unresponsive to breakthrough analgesia or if the pain is worse on movement.
Seek specialist advice before prescribing strong opioids for patients with moderate to severe renal or hepatic impairment.
Starting and Titrating:
If oral opioids not suitable:
Prescribe regular laxative for all patients and consider when required or regular anti-emetics. Nausea is often self-limiting.
Drowsiness may occur at initiation and following an increase or after a when required dose but is usually self-limiting.
Psychological dependence and opioid tolerance are very rare in patients with advanced illness.
Use lower doses and increase analgesia more slowly if individual is frail, elderly or has renal impairment.
Use immediate release morphine (tablet or oral solution) 2.5-10mg four hourly depending on pain severity, general condition and previous use of weak opioids.
Increase four-hourly dose if pain not controlled - suggested increments are:
Once the daily opioid requirement is established with stable doses over at least 24 hours conversion to a slow release preparation can occur. Add up the total daily dose of opioid used and divide by 2 for a twice daily long acting regime.
To start an individual using modified release, use regular Zomorph, prescribe 10-15mg 12 hourly.
Records of administered breakthrough pain doses are essential to allow for the effective assessment of pain control and timely adjustments to the continuous analgesic dose.
Where individuals are able to take regular oral opioid medication, and there is thought to be no problem with absorption, there is no theoretical benefit (i.e. no greater potency or efficacy) in administering opioids parentally.
For all opioids administered by continuous subcutaneous infusion:
Morphine
and
1mg oral morphine = 0.5mg SC morphine (2:1 conversion ratio)
If the pain has been poorly controlled before the switch to a syringe driver, it may be necessary to calculate the baseline dose of morphine sulfate as above, but then increase the syringe driver content by 20% to improve pain control.
It may also be necessary to give when required SC doses to alleviate pain until the syringe driver has had time to work effectively (approximately 4 hours).
If after 6-12 hours, pain is still poorly controlled, then a dose increment of 20% in the syringe driver should be considered.
Depending on clinical circumstances, the dose increments may need to be lower or higher than the suggestion of 20%.
If the volume of medications in the syringe driver is a concern, advice should be sought from the specialist palliative care team. Do not start new patients on diamorphine 5mg or 10mg injection as supplies will be unpredictable in the future (DHSC, March 2020).
Patients receiving continuous analgesia infusions may still experience acute episodes of pain. These often occur in response to movement or dressing changes etc. It is essential that patients are able to receive additional doses of analgesia to treat this breakthrough pain.
A separate bolus subcutaneous morphine sulfate dose should be prescribed for use as required.
Morphine sulfate SC dose for breakthrough pain = 24 hour morphine sulfate SC dose divided by 6
If 24 hour infusion dose is increased the 'breakthrough' dose will also need to be recalculated.
Records of administered breakthrough pain doses are essential to allow for the effective assessment of pain control and timely adjustments to the continuous analgesic dose
Buprenorphine patches are rarely used in palliative medicine, but some patients may already be on these. If this is the case, continue them and, in the event that they need to be altered – seek advice.
Remember to check for patches in the unwell palliative patient – they may forget to mention these in their tablet list.
Oral morphine to fentanyl patch 150:1 conversion ratio
3.75mg/hour oral morphine = 0.025mg/hour fentanyl patch = 25micrograms/hour fentanyl patch
Indications for fentanyl patches:
Notes
Refer to prescribing notes in section 4.7.2 Opioid analgesics for further prescribing notes and MHRA Drug Safety Updates.
The first fentanyl patch needs to be applied at the same time as the last 12 hourly modified release dose of morphine.
Patients will usually require 3 x 4 hourly doses until the subcutaneous depot has built up i.e. continue immediate release morphine for 6-12 hours.
Patients who will occasionally need to be converted from a fentanyl patch to an alternative opioid. Such switches can be complex given the long half-life of the drug when it is delivered by a patch. In such cases consult Palliative Care Team for advice.
Continue patch and change every 72 hours as before.
If pain occurs, give breakthrough doses of oral/SC opioid. The breakthrough dose should be approximately one sixth (1/6) of the total opioid dose. When calculating doses refer to the guide to equivalent doses for opioid drugs here or contact the specialist palliative care team.
If 2 or more breakthrough doses are needed in 24 hours, consider starting an opioid syringe driver and continue the current dose of fentanyl patch. The starting dose of opioid in the syringe driver should be calculated using the total breakthrough doses given in the previous 24 hours.
E.g. if patient is on fentanyl 25mcg/hr patch, and has received 2 doses of morphine sulfate 10mg oral, then you may decide to start morphine sulfate injection 10mg/24hr via SC syringe driver.
Once patient is on fentanyl patch and opioid via syringe driver
Step 1: Calculate new breakthrough dose of 'as required' opioid
E.g. using example above: fentanyl 25mcg/hr patch is equivalent to 30 - 45mg/24hr morphine sulfate injection. Syringe driver is delivering an additional 10mg/24hr, hence total regular dose received by patient is 40 - 55mg SC in 24hr. Based on that, an appropriate breakthrough dose might be morphine sulfate injection 7.5mg SC as required.
Step 2: Calculating an increase in opioid dose via syringe driver
E.g. continuing example above:
If you are in any doubt about these calculations, ask for specialist advice
If symptoms persist contact the local specialist palliative care team
The conversions quoted are approximate and vary between individuals. Conversion ratios are never more than an approximate guide.
Caution is always necessary because of wide inter-individual variation in opioid pharmacokinetics and other variables such as nutritional status and concurrent medication.
At higher doses these variations require the consideration of a reduction in the dose when converting from one strong opioid to another as there is a risk of sedative side effects.
Careful monitoring during conversion is necessary to avoid both under dosing and excessive dosing.
Drug conversions can be challenging and it is often helpful to double check them with a colleague.
If in any doubt seek specialist palliative care advice.
A guide to equivalent doses of opioids used in palliative care has been developed by local specialists across the region. Please note this is not a definitive set of equivalences. The guide is hosted on the Rowcroft Hospice website and can be accessed here.
Please be aware that supplies of diamorphine 5mg and 10mg injection will be unpredictable for the foreseeable future (DHSC, March 2020). For patients requiring subcutaneous pain relief, morphine sulfate injection is the first line opioid if clinically appropriate. If volume of medications in the syringe driver is a concern, advice should be sought from the specialist palliative care team
Do not start new patients on diamorphine 5mg and 10mg injection, and review patients currently receiving these injections. See section 4.7.2 Opioid analgesics for a list of preparations
There are two main types of breakthrough pain:
Two important first steps in managing breakthrough pain are to optimise the “around the clock" analgesia (background analgesia), and to avoid or manage the precipitating factors.
It is essential that patients are able to receive additional doses of analgesia to treat this breakthrough pain.
If background analgesia doses change remember to change breakthrough doses.
Records of administered breakthrough pain doses are essential to allow for the effective assessment of pain control and timely adjustments to the continuous analgesic dose.
Treatment for breakthrough pain is often satisfactory with immediate release oral morphine. When more rapid onset and briefer duration of action are of significant clinical importance the greater cost of sub-lingual fentanyl citrate may be justified.
True opioid intolerance is very rare.
Opioids will often cause adverse effects which can usually be treated successfully:
Rarely a patient has an idiosyncratic adverse effect which necessitates a reduction in dose or change to an alternative opioid (see below).
Opioid induced cognitive failure produces psychomotor disturbance, cognitive impairment, drowsiness or hallucinations.
Opioid induced hyperexcitability produces myoclonus, hyperalgesia and allodynia. Both syndromes are important to recognise and respond to by reducing the dose of opioid or by a change of opioid.
Opioid overdose features include drowsiness and respiratory depression. Patients nearing the end of their life are also drowsy and experience breathing changes (e.g. Cheyne-Stokes breathing) due to the advanced stage of their illness. This makes differential-diagnosis difficult at this time. In this setting the incidence of life threatening respiratory depression due to opioids is extremely rare.
Particular caution is needed with fentanyl patches due to their long duration of action even once the patch is removed.
Naloxone is very rarely required in palliative care patients. The use of naloxone at the end of life can cause a pain crisis resulting in poor symptom control and agitation for the patient and extreme distress to their family witnessing this. This significant burden needs to be factored into any treatment decision in this setting.
If, following assessment, professionals are uncertain whether the patient is nearing the end of their life; consider seeking advice from the specialist palliative care team. If the patient is thought to be dying, staff should provide appropriate end of life care.
If toxicity syndromes occur or if rapid escalation of doses of morphine fails to produce analgesic effect, an alternative strong opioid can be used. Fentanyl or oxycodone are logical alternatives to morphine, although methadone is most helpful in hyperexcitability syndromes.
Expert advice should be sought about possible opioid toxicity and its best management.
In addition to an excessive opioid dose due to over-infusion or an excessive bolus dose, the commonest reasons for development of opioid toxicity in the palliative setting are:
Seek specialist advice when managing palliative patients with renal impairment.
If eGFR is less than 30mL/minute/1.73m2 use renal end of life care plan for opioid use.
NSAIDs should not usually be prescribed in renally impaired patients unless on the recommendation of a specialist.
Close monitoring of renally impaired patient is required whichever opioid is used.
Accumulation of opioid of active metabolites may lead to a prolonged duration of action and increased toxicity.
When possible in renally impaired patients, optimize the use of adjuvant analgesia before introducing an opioid.
If opioids are required:
All principles of pain management apply for the use of adjuvant analgesics.
Ensure the first line adjuvant analgesic is at its pharmacologically effective dose level and interval before changing to/adding second line drugs.
Many of the drugs classified as adjuvant analgesics were developed and released for clinical indications other than pain.
If progressive pain control is not being achieved – seek advice
Please refer to Neuropathic pain
Used for the treatment of neuropathic pain caused by infiltrating cancers. They are particularly important when neuropathic pain is associated with limb weakness.