Conversions of Strong Opiates

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Transcript Conversions of Strong Opiates

Common issues:
Opioid Prescribing and LCP
GP Clinical Governance Meeting
13th of July 2011
Dr Marion Lieth
Consultant in Palliative Medicine, Bolton Hospital
and Bolton Hospice
Outline
 Common things about opioids:
 Some basics about prescribing opioids
 Common side effects and how to deal with them
 Fentanyl patch
 Opioid switch
 Care of the dying
 Case scenarios for discussion – Prescribing for LCP
Strong Opiates Used in Palliative
Care
 Morphine (oral, subcut)
 Oxycodone (oral, subcut)
 Diamorphine ( subcut)
 Fentanyl (transdermal, buccal, transmucosal)
 Alfentanyl (subcut)
 Hydromorphone (oral, subcut)
 Buprenorphine (transdermal)
 Methadone
Some basics about opioids
 All strong opiates provide effective analgesia
 All have the same potential side effects.
 Tolerated differently by different patients depending upon the
dose required and coexisting factors eg renal function
 Use oral route if possible
 Morphine is 1st line
 Start small, give regularly, review often and titrate
 NPSA alert – max 30-50% increase
 Patient factors, pain intensity, side-effects
 PRN dose depends on total 24 hour dose
 In general 1/6th
 Provide explanations and deal with concerns
Common side effects
 Nausea and vomiting
 often in the first days, occasionally persistent
 Metoclopramide or haloperidol
 Constipation
 Stimulant + softener laxative
 A sense of drowsiness, often improves after a few days
 Confusion (particularly the elderly)
 Small initial dose and titrate slowly, check renal function, warn
the patient
Neurotoxic side effects
 Hallucinations
 Bad dreams
 Myoclonus
 Delirium
 Drowsiness
 Dose and patient dependent
 Poor renal function
 Check RF, reduce dose, switch opioid
Serious side effects
 Drug dependence:
 common fear
 rare if prescribed and used properly
 Respiratory depression:
 Rare if prescribing guidelines are followed
Fentanyl patch
 Not better then any other opioid
 Non-oral route
 E.g. Head and neck cancers
 Useful in renal failure
 Compliance
 Slow to titrate
 Not good for acute or unstable pain
 Potent analgesic
 Fentanyl 25mcg her hour = ???
oral Morphine over 24 hrs
Fentanyl patch
 Not better then any other opioid
 Non-oral route
 E.g. Head and neck cancers
 Useful in renal failure
 Compliance
 Slow to titrate
 Not good for acute or unstable pain
 Potent analgesic
 Fentanyl 25mcg her hour = 60-90mg oral Morphine over 24 hrs
 Codeine 240mg a day = ???? oral Morphine over 24 hours
Fentanyl patch
 Not better then any other opioid
 Non-oral route
 E.g. Head and neck cancers
 Useful in renal failure
 Compliance
 Slow to titrate
 Not good for acute or unstable pain
 Potent analgesic
 Fentanyl 25mcg her hour = 60-90mg oral Morphine over 24 hrs
 Codeine 240mg a day = 24mg oral Morphine over 24 hours
Opioid switch – Reasons:
 One opioid does not work better then other
 Patient preference
 Problems with route of administration
 Side effects; intolerable, dose limiting
 Renal failure
 Volume of injection
Principles of Conversions
 Convert for the right reasons
 Confirm the analgesia used so far
 Don’t guess, use tables and calculations
 Tables are only a guide – if high doses convert conservatively
and titrate
 Review the outcome of the drug change and adjust the dose
if necessary
Basic Conversions
Potency
oral codeine
oral morphine
oral morphine
sc morphine
oral morphine
oral Oxycodone
oral oxycodone
sc oxycodone
oral morphine
sc diamorphine
 Fentanyl patch 25mcg/hour is equivalent to about ??? mg of
oral morphine per day.
Basic Conversions
Potency
oral codeine
oral morphine
1:10
oral morphine
sc morphine
1:2
oral morphine
oral Oxycodone
1:2
oral oxycodone
sc oxycodone
1:2
oral morphine
sc diamorphine
1:3
 Fentanyl patch 25mcg is equivalent to about 60-90 mg of oral
morphine per day.
Analgesia when patient is dying
 If analgesia hasn’t been required so far
 prescribe morphine 2.5- 5mg sc prn
 If on regular strong opioids by mouth
 Convert regular long-acting opioid dose to sc
 sc Morphine if on oral morphine
 sc Oxycodone if on oral oxycodone
 divide the oral dose by 2
 Timing?
 Prescribe PRN (a sixth of 24hr dose)
Fentanyl patches and syringe
drivers
 Continue the fentanyl patch
 Write up PRN opioid dose
 If in pain:
 Add morphine or oxycodone to the syringe driver
 ‘Rule of thumb’ – start syringe driver with 2x prn dose over 24
hours = 30% increase
 Recalculate PRN dose
 Fenanyl patch + syringe driver
Any questions?
Q 1.
A district nurse contacts you to suggest a patient is started
on the LCP.
The patient has been taking 90mg of morphine MR bd and
two additional doses of morphine soln 30mg each day.
How would you respond to this and what do you prescribe?
Answer 1.
 Why does she think that the patient is dying? Check history,
drugs, exclude reversible factors
 Has pain been well controlled on the oral morphine?
 If you think a syringe driver is required and depending on
above and your assessment:
 MST 90mg bd + Oramporph 30mgx2
 240mg oral morphine per day
 120mg morphine sc/24hrs
 20mg morphine sc prn
Q2
A district nurse contacts you to suggest a patient is started
on the LCP.
The patient has been taking 200mg Oxycontin bd and the
pain has been well controlled on this. There are no reversible
factors, the patient is dying and unable to swallow.
What do you prescribe?
Answer 2
 Switch to sc infusion
 Oxycontin 200mg bd
 Oral Oxycodone 400mg over 24 hours
 Oxycodone 200mg sc over 24 hours
 Concentration in ampule:
 Oxycodone 10mg/ml
 20 ml
 Maximum volume in syringe driver?
 20ml syringe holds 16-17ml
 30ml syringe holds 22ml
Answer 2
3 options:
 Why Oxycodone?
Use 30ml syringe, e.g. holds 22ml – but little volume left for
other drugs
2. Switch to Diamorphine
1.



Oral Oxycodone 400mg/24 hours
Oral Morphine 800mg/24 hours
Sc Diamorphine 800 divided by 3 = 260mg sc Diamorphine /24 hours
Ring Hospice advice line
3.


Confirm numbers
Other options – e.g Alfentanyl
Q3
A patient started on a fentanyl patch only last week. The dose
is now 50mcg. The patient continues to have pain and needs
prn morphine 10mg every 2 hours or so.
The district nurse requests review. She thinks a syringe driver
is indicated.
What do you suggest?
Answer 3
 What about the pain? does the prn morphine help? Prn
dose appropriate? Can patient take oral Morphine? Is the
oral morphine absorbed? How many prn doses exactly?
 Are there other causes of distress? Is the patient opioid
toxic?
 Try appropriate PRN Morphine dose – 30mg oral, 15mg
sc morphine
 Use of syringe driver and dose depends on these answers
 If able to take by mouth – regular oral Morphine
 Morphine sc 30-60mg/24 hr could be reasonable.
 Continue the patch
Q4
A patient has a fentanyl patch 75mcg in place and 60mg
morphine in a syringe driver.
What is the correct prn dose of morphine?
Answer 4
 The prn dose should be calculated by thinking about both the
patch and the morphine infusion, ie the total 24 hr dose of
opiate
3 Different ways:
1. PRN for each and add together:
 Fentanyl patch 75mcg/hr
 prn oral morphine 40mg
 prn sc morphine 20mg
 Morphine sc infusion 60mg/24h
 prn 10mg sc morphine
 Therefore: PRN sc morphine 20+10 = 30mg
Answer 4
Convert to total oral daily dose, then PRN for total
 Fentanyl patch 75mcg/hour
equivalent oral Morphine 270mg/24hours
 Morphine sc infusion 60mg/24 hours
Equivalent oral Morphine 120mg/24hours
 Total equivalent oral Morphine dose 390mg/24hours
 PRN oral Morphine 60mg
 PRN sc Morphine 30mg
2.
3.
Ring a friend
 Bolton Hospice Advice line – 01204 663066
Q5
You have seen a patient who you think is dying. After discussion
with the family and district nurse you commence the LCP.
The patient normally takes Oxycodone 30mg bd and Cyclizine
50mg tds. His symptoms are well controlled on this.
What do you prescribe?
Answer 5
 Switch regular Oxycontin to syringe driver
 Continue regular anti-emetic
 Anticipatory prescribing for other common symptoms of
dying patient – PRN medication
 Pain
 Nausea
 Respiratory secretions
 Distress/Agitation
 Breathlessness
Answer 5
 This patient is on Oxycontin 30mg bd, Cyclizine 50mg tds
 Syringe driver:
 Oxycodone 30mg sc infusion over 24 hours
 Oxycodone and Cyclizine are not compatible in syringe
 Levomepromazine 6.25-12.5 mg sc infusion over 24 hours
 Anticipatory PRN medication:
 Oxycodone 5mg sc
 Levomepromazine 6.25mg sc 4-6 hourly
 Hyoscine hydrobromide 400microgram sc
 Be aware – similar name – Hyoscine butylbromide (Buscopan)
 Midazolam 2.5 -5 mg sc, max 20mg over 24 hour
 If requires more – needs review
Advice
 Guidelines
 Conversion charts
 The palliative care team are always happy to help
 Bolton hospice advice service Tel 663066
New syringe drivers
 Recent NPSA alert
 In Bolton acute hospital, community services and hospice
have switched from Graesby pumps to McKinley T34 syring
drivers on 15th of June 2011
 Nursing staff have been trained in new device
 No difference for prescribing
 Maximum volume remains unchanged
 17ml in 20 ml syringe
 22ml in 30 ml syringe