Syringe drivers Flashcards
What does CSCI stand for?
continuous subcutaneous infusion
Why use syringe drivers?
to deliver a medication for a persistent symptom that needs persistent management
when oral route is unavailable
What symptoms can be managed with a syringe driver at the end of life?
pain
agitation
secretions
nausea + vomiting
breathlessness
What is anticipatory prescribing?
on PRN section
for all patients deemed to be end of life
something for all possible symptoms patient might experience so can be given quickly if needed
must be prescribed SC
Why is there more than one prescription box on a syringe driver prescription sheet if you can put 4 drugs in a syringe?
compatibility - not all drugs can be mixed
more than 4 drugs needed sometimes
easier to review/change doses
volume
Where are syringe driver cannulae normally sited?
centrally on torso - extremities shut down at end of life
What diluent can be used for syringe drivers?
normal saline or water for injection (some drugs can only be one or the other)
What is the rate for a syringe driver on the prescription chart?
over 24 hours
Why are syringe drivers giving medicines SC not IV?
not IV as can be hard to get veins at end of life as peripheries shut down
What is the volume on a syringe driver prescription?
17ml (for 20ml syringe)
or 22ml (for 30ml syringe)
Management of secretions at end of life
drugs
suction
position change
no intervention but talk to family
What drugs can be used to manage secretions at the end of life?
anticholinergics:
- hyoscine butylbromide (buscopan)
- hyoscine hydrobromide
- glycopyrrhonium
Why is hyoscine butylbromide preferred to hyoscine hydrobromide?
butylbromide does not cross BBB - so fewer side effects
hydrobromide can be sedating
What anti-emetics are commonly used at end of life?
metoclopramide
cyclizine
haloperidol
levomepromazine
(ondansetron has poor compatibility with other drugs and doesn’t dissolve as well - generally avoid but used in parkinsons patients)
What can cause agitation at end of life?
overwhelming other symptom (eg. pain)
reversible causes
delirium
anxiety/fear
What drugs can be used for delirium at end of life?
anti-psychotics:
haloperidol
levomepromazine
What drugs can be used for anxiety/fear at end of life?
benzodiazepines:
midazolam
lorazepam
What drugs can be used for breathlessness at the end of life?
opiates (morphine)
benzodiazepines (midazolam)
Why is levomepromazine not really used outside of palliative care?
works on most of receptors in vomiting pathway
therefore many side effects (mainly sedation + postural hypotension)
What opioids are used in palliative care?
morphine (not good in renal failure)
diamorphine
oxycodone
alfentanil (good when eGFR<30 but short half life)
fentanil
What dose of morphine should be started in a syringe driver if a patient is opiate naive?
start at low dose
5-10mg morphine in syringe driver
What would oral morphine 30mg BD dose be for a syringe driver?
oral morphine –> SC morphine = /2
60mg morphine in 24h PO = 30mg morphine in 24h SC
prescribe 30mg SC morphine
Why is a lower dose of SC opiates needed compared to PO?
SC has higher bioavailablity so more is absorbed and little is metabolised before action
When putting opioids in a syringe driver, what should be crossed off the regular prescriptions?
any pre-existing opioids
(Do not cross off PRN)
What should you look for on a patient when calculating their total analgesic dose?
any patches
What dose of analgesia should be put in a syringe driver if patient had been on opioids leading up to this?
total daily dose
add up regular dose + taken PRNs in last 24h
How is analgesia PRN dose calculated for palliative care?
calculate total 24h dose (total regular + taken PRNs in last 24h)
divide by 6
(works for morphine + oxycodone)
(divide by 6 as doses usually last around 4h, so 6 in 24h)
What does high dose metoclopramide increase the risk of?
extra-pyramidal side effects + risk of colic
What anti-emetics are good for brain mets?
cyclizine
dexamethasone
What is the dose conversion for anti-emetics from PO to SC?
PO and SC doses the same
