Read on Twitter
Opioid toxicty: A thread (with a palliative theme)
Let’s start by thinking about tue difference between side-effects of opioids from toxicity.
Let’s start by thinking about tue difference between side-effects of opioids from toxicity.
Side-effects: the secondary, usually undesirable effects other than pain relief
Constipation
Dry mouth
Somnolence
Itch
Euphoria
Nausea
Small pupils- not a sign of toxicity!
Constipation
Dry mouth
Somnolence
Itch
Euphoria
Nausea
Small pupils- not a sign of toxicity!
Toxicity: Accumulation of opioid or its metabolites leading to-
Excessive somnolence
Hallucinations
Neurotoxicity
Cognitive dysfunction
Reduced respiratory rate
NOT overdose which produces life-threatening respiratory depression
Excessive somnolence
Hallucinations
Neurotoxicity
Cognitive dysfunction
Reduced respiratory rate
NOT overdose which produces life-threatening respiratory depression
Hallucinations typically are:
Shadows or movement in periphery of vision.
Hypnagogic/hynopompic
Vivid, colourful dreams
Nightmares
Parasitosis- sensation of insects on skin
Small animals in room
and Many other forms of visual and tactile hallucination
Shadows or movement in periphery of vision.
Hypnagogic/hynopompic
Vivid, colourful dreams
Nightmares
Parasitosis- sensation of insects on skin
Small animals in room
and Many other forms of visual and tactile hallucination
Neurotoxicity
Often takes the form of myoclonic jerks. Sudden and localised.
Those dream you have when you miss a step and wake yourself with jolt!
Often most evident when holding a cup up to drink or cutlery. Patients often drop their phones.
Often takes the form of myoclonic jerks. Sudden and localised.
Those dream you have when you miss a step and wake yourself with jolt!
Often most evident when holding a cup up to drink or cutlery. Patients often drop their phones.
Cognitive dysfunction
Can range from deepening somnolence to full blown florid delirium.
Patients become unable to eat or drink. Risk of falls increases. Capacity may be lost and hospital stay prolonged. Risk of aspiration, pressure damage and DVT/PTE increased.
Can range from deepening somnolence to full blown florid delirium.
Patients become unable to eat or drink. Risk of falls increases. Capacity may be lost and hospital stay prolonged. Risk of aspiration, pressure damage and DVT/PTE increased.
Respiratory rate
Opioids reduce respiratory rate, sensation of breathlessness and the cough reflex via action on the vagus nerve and brainstem.
In toxicity oxygenation/ ventilation is maintained
In overdose oxygenation/ ventilation is impaired
Opioids reduce respiratory rate, sensation of breathlessness and the cough reflex via action on the vagus nerve and brainstem.
In toxicity oxygenation/ ventilation is maintained
In overdose oxygenation/ ventilation is impaired
Assessment:
ABCDE as always
Resp rate and oxygen sats
GCS
Small pupils are a clue to opioid use but no more than that!
Look for myoclonus
Ask about dreams/hallucinations but explain why- patients can think they are going mad.
ABCDE as always
Resp rate and oxygen sats
GCS
Small pupils are a clue to opioid use but no more than that!
Look for myoclonus
Ask about dreams/hallucinations but explain why- patients can think they are going mad.
Tips
Check renal function: many opioids and their metabolites accumulate in renal failure leading to toxicity.
Check the kardex: what has been given and when. Is the dose correct?
Other medications can potentiate opioid actions e.g. gabapentin, pregabalin
Check renal function: many opioids and their metabolites accumulate in renal failure leading to toxicity.
Check the kardex: what has been given and when. Is the dose correct?
Other medications can potentiate opioid actions e.g. gabapentin, pregabalin
Has the cause/source of pain been addressed in another way?
A new painkiller such as an NSAID
An intervention such as a nerve block
or radiotherapy.
A sudden down regulation in opioid receptors in CNS leads to higher plasma levels of opioid even with the same dose = toxicity
A new painkiller such as an NSAID
An intervention such as a nerve block
or radiotherapy.
A sudden down regulation in opioid receptors in CNS leads to higher plasma levels of opioid even with the same dose = toxicity
Beware the hidden opioid
Look carefully for fentanyl patches.
Has an extra patch been applied?
Does the Patient have a fever, if so the increased blood flow to skin can lead to increased absorption from the patch. Same can happen when sitting in warm sunshine.
Look carefully for fentanyl patches.
Has an extra patch been applied?
Does the Patient have a fever, if so the increased blood flow to skin can lead to increased absorption from the patch. Same can happen when sitting in warm sunshine.
Management when RR>8 and sats/BP maintained:
If pain well controlled: reduce dose of opioid (speak with palliative care/pain team for guidance)
Maintain hydration: IV or scut
Correct renal failure
Explain what is happening to patient, family and ward staff
If pain well controlled: reduce dose of opioid (speak with palliative care/pain team for guidance)
Maintain hydration: IV or scut
Correct renal failure
Explain what is happening to patient, family and ward staff
If Opioid toxic and pain is not controlled then there is NO scope to increase current opioid.
Consider alternatives to opioid for pain. NSAID, non-drug.
Correct renal failure and hydrate.
Discuss with palliative care/pain team about rotating to a different opioid.
Consider alternatives to opioid for pain. NSAID, non-drug.
Correct renal failure and hydrate.
Discuss with palliative care/pain team about rotating to a different opioid.
Opioid rotation
Different opioid in theory = different opioid receptor affinities, different metabolites and new sites of metabolism.
There are standard opioid conversions used to work out dose of opioid when rotating.
The Spot app is a good tool https://www.nhsresearchscotland.org.uk/uploads/tinymce/P30.pdf
Different opioid in theory = different opioid receptor affinities, different metabolites and new sites of metabolism.
There are standard opioid conversions used to work out dose of opioid when rotating.
The Spot app is a good tool https://www.nhsresearchscotland.org.uk/uploads/tinymce/P30.pdf
Tips
Do not initiate, rotate to or from fentanyl patches without advice from specialist.
Patients can withdraw from old opioid when rotated to a new one. Prescribe a a few final breakthrough doses of old opioid to cover the first 48 hours of the changeover.
Do not initiate, rotate to or from fentanyl patches without advice from specialist.
Patients can withdraw from old opioid when rotated to a new one. Prescribe a a few final breakthrough doses of old opioid to cover the first 48 hours of the changeover.
Naloxone is used to reverse opioid overdoses.
It Should be reserved for life threatening/peri-arrest situations when oxygenation/ventilation BP are compromised.
There are specific guidelines for management of opioid overdose in non-palliative patients.
It Should be reserved for life threatening/peri-arrest situations when oxygenation/ventilation BP are compromised.
There are specific guidelines for management of opioid overdose in non-palliative patients.
Most patient who are opioid toxic can be supported without naloxone.
In patients who have cancer pain or chronic pain think carefully before using naloxone.
Needless reversal of opioid toxicity without life threatening features will cause acute pain AND withdrawal !
In patients who have cancer pain or chronic pain think carefully before using naloxone.
Needless reversal of opioid toxicity without life threatening features will cause acute pain AND withdrawal !
If a patient on long term opioids for severe pain needs naloxone then go low and slow unless it is a genuine life threatening emergency
See link below for example of guidance used in Scotland
https://www.palliativecareguidelines.scot.nhs.uk/guidelines/medicine-information-sheets/naloxone.aspx
See link below for example of guidance used in Scotland
https://www.palliativecareguidelines.scot.nhs.uk/guidelines/medicine-information-sheets/naloxone.aspx
Although the risk of opioid toxicity can be reduced by slow and carefully monitored titration of doses there is no full proof way to predict or prevent it.
Early Recognition is the key
Ask about those dreams, hallucinations and watch for spilled tea and flying cutlery.
Early Recognition is the key
Ask about those dreams, hallucinations and watch for spilled tea and flying cutlery.
