Continuous subcutaneous infusions (syringe drivers)
BNF Prescribing in Palliative Care
Portable continuous infusion devices, such as syringe drivers, provide good control of symptoms.
Indications for the parenteral route are:
The patient is unable to take medicines by mouth owing to nausea and vomiting, dysphagia, severe weakness, or coma
There is malignant bowel obstruction and surgery is inappropriate
When the patient does not wish to take regular medication by mouth.
Aligning contents of syringe driver to end-of-life symptoms
Pain control
Diamorphine hydrochloride is the preferred opioid since its high solubility permits a large dose to be given in a small volumeSyringe SC diamorphine dose over 24hr is one-third the total oral morphine dose over 24hr
Syringe SC morphine dose over 24hr is half the total oral morphine dose over 24hr
Syringe SC oxycodone dose over 24hr is half the total oral oxycodone dose over 24hr
So, 60mg oral morphine/24hr equates to 30mg SC morphine/24hr equates to 20mg SC diamorphine/24hrIf breakthrough pain occurs give SC/IM dose that is 1/10 to 1/6 of the total 24-hour SC infusion dose
Nausea and vomiting
Haloperidol (2.5-10mg/24hr)
Levomepromazine (5–25 mg/24 hours)
Cyclizine is particularly likely to precipitate if mixed with diamorphine or other drugs
Octreotide reduces intestinal secretions and vomiting arising from bowel obstruction.Agitation, confusion and restlessness
Haloperidol (5–15 mg/24 hours)
Levomepromazine (12.5–50 mg/24 hours)
Midazolam (Initially 10–20 mg/24 hours, adjusted according to response; usual dose 20–60 mg/24 hours)Excessive respiratory secretions
Hyoscine butylbromide (20–120 mg/24 hours)
Glycopyrronium bromide (0.6-1.2mg/24hr)Bowel colic
Hyoscine butylbromide (60–300 mg/24 hours)
Glycopyrronium bromide (0.6-1.2mg/24hr)Convulsions
Midazolam (Initially 20–40 mg/24 hours)
Compatibility with diamorphine
Diamorphine can be given by subcutaneous infusion in a strength of up to 250 mg/ml
<40 mg/mL diamorphine use either water for injections or physiological saline (sodium chloride 0.9%) as diluent
>40 mg/mL diamorphine use only water for injections as diluent (to avoid precipitation)
The following can be mixed with diamorphine:
Cyclizine may precipitate with diamorphine or sodium chloride diluent 0.9%
Cyclizine should be mixed with water for injection to reduce the chance of precipitation.Metoclopramide can cause skin reactions, can cause discolouration of infusion
Dexamethasone may precipitate
Haloperidol may precipitate if haloperidol concentration is above 2 mg/mL
Hyoscine butylbromide
Levomepromazine
Metoclopramide
Midazolam