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Subcutaneous infusion solution should be monitored
regularly both to check for precipitation (and discolora-
tion) and to ensure that the infusion is running at the
correct rate.
Problems encountered with syringe drivers
The
following are problems that may be encountered with
syringe drivers and the action that should be taken:
.
if the subcutaneous infusion runs
too quickly
check
the rate setting and the calculation;
.
if the subcutaneous infusion runs
too slowly
check
the start button,
the battery,
the syringe driver,
the
cannula, and make sure that the injection site is not
inflamed;
.
if there is an
injection site reaction
make sure that
the site does not need to be changed—firmness or
swelling at
the site of
injection is not
in itself
an
indication for change,
but pain or obvious inflam-
mation is.
Equivalent doses of morphine sulphate and
diamorphine hydrochloride given over 24
hours
These equivalences are approximate only and should
be adjusted according to response
MORPHINE
PARENTERAL
DIAMORPHINE
Oral
morphine
sulphate
Subcutaneous
infusion of
morphine sulphate
Subcutaneous
infusion of
diamorphine
hydrochloride
over 24 hours
over 24 hours
over 24 hours
30 mg
15 mg
10 mg
60 mg
30 mg
20 mg
90 mg
45 mg
30 mg
120 mg
60 mg
40 mg
180 mg
90 mg
60 mg
240 mg
120 mg
80 mg
360 mg
180 mg
120 mg
480 mg
240 mg
160 mg
600 mg
300 mg
200 mg
780 mg
390 mg
260 mg
960 mg
480 mg
320 mg
1200 mg
600 mg
400 mg
If breakthrough pain occurs give a subcutaneous (pre-
ferable) or intramuscular injection equivalent to one-
tenth to one-sixth of the total 24-hour subcutaneous
infusion dose. It is kinder to give an intermittent bolus
injection subcutaneously—absorption is smoother so
that the risk of adverse effects at peak absorption is
avoided (an even better method is to use a subcuta-
neous butterfly needle).
To minimise the risk of infection no individual subcu-
taneous infusion solution should be used for longer
than 24 hours.
Prescribing for the elderly
Old people, especially the very old, require special care
and consideration from prescribers.
Medicines for Older
People
, a component document of the National Service
Framework for Older People,
1
describes how to max-
imise the benefits of medicines and how to avoid exces-
sive, inappropriate, or inadequate consumption of med-
icines by older people.
Appropriate
prescribing
Elderly
patients
often
receive multiple drugs for their multiple diseases.
This
greatly increases the risk of drug interactions as well as
adverse reactions, and may affect compliance (see Tak-
ing medicines to best
effect under General
guidance).
The balance of
benefit
and harm of
some medicines
may be altered in the elderly. Therefore, elderly patients’
medicines should be reviewed regularly and medicines
which are not of benefit should be stopped.
Non-pharmacological measures may be more appropri-
ate for symptoms such as headache, sleeplessness, and
lightheadedness when associated with social stress as in
widowhood, loneliness,
and family dispersal.
In some cases prophylactic drugs are inappropriate if
they are likely to complicate existing treatment
or
introduce unnecessary side-effects, especially in elderly
patients with poor prognosis or with poor overall health.
However,
elderly patients should not be denied medi-
cines which may help them,
such as anticoagulants or
antiplatelet
drugs
for
atrial
fibrillation,
anti-
hypertensives,
statins,
and drugs for osteoporosis.
Form of
medicine
Frail
elderly patients may have
difficulty swallowing tablets;
if
left in the mouth,
ulcer-
ation may develop.
They should always be encouraged
to take their tablets or capsules with enough fluid,
and
whilst in an upright position to avoid the possibility of
oesophageal ulceration. It can be helpful to discuss with
the patient the possibility of taking the drug as a liquid if
available.
Manifestations of ageing
In the very old,
manifes-
tations of
normal
ageing may be mistaken for disease
and lead to inappropriate prescribing.
In addition,
age-
related muscle weakness and difficulty in maintaining
balance should not be confused with neurological
dis-
ease.
Disorders such as lightheadedness not associated
with postural
or postprandial
hypotension are unlikely
to be helped by drugs.
Sensitivity
The nervous system of elderly patients is
more sensitive to many commonly used drugs,
such as
1.
Department
of
Health.
National
Service Framework for
Older People. London: Department of Health, March 2001.
24
Prescribing for the elderly
BNF 61
Prescribing for the elderly