Parenteral infusions and syringe drivers
Whilst the preferred route of medication administration in paediatric palliative care is the oral one, there may be occasions when this is impractical or undesirable. The use of a subcutaneous or intravenous infusion using a syringe driver to deliver
medications has certain advantages;
- there is less patient discomfort as the need for repeated injections is reduced compared to intramuscular or intermittent subcutaneous administration
- multiple symptoms can be controlled by combining drugs in the syringe or reservoir of the pump
- the plasma drug level remains relatively constant throughout the day
- the devices are portable and lightweight allowing the patient to maintain mobility
Nursing support is required to maintain an infusion in the home environment but community-based services (eg. Palliative care, Royal District Nursing Service, Hospital in the Home) are available to make daily visits. It is worth noting that not all medications
can be given subcutaneously (see below).
Subcutaneous (or for those children with central access devices, intravenous) infusions are a useful alternative for children who
- Can not tolerate oral medication
- Refuse to take oral medication
- Are nauseated or vomiting
- Are not able to absorb enteral forms of medication
- Are unconscious
Often families may view the institution of a subcutaneous or intravenous infusion as a sign of deterioration or a "last resort". Obviously, there are occasions where the need for a parenteral route of administration comes about as a result of the child's
worsening condition but more often, a route change is initiated for pragmatic reasons. Where appropriate, families should be reassured that the parenteral administration of medication is merely another treatment option which may be more effective, more convenient or
There are a number of syringe drivers with varying degrees of sophistication available. As a general principle, use of a syringe driver capable of delivering a bolus of medication in addition to a continuous (background) infusion is preferred.
|NO RECOMMENDATION IS INTENDED OR IMPLIED AS TO THE APPROPRIATENESS OR OTHERWISE OF ANY PARTICULAR TYPE OR MAKE OF SYRINGE DRIVER. |
One of the more common types of syringe driver and one of the easiest to use is the SIMS GRASEBY range of ambulatory syringe drivers. A variety of models are available. For subcutaneous infusions, the MS26 model syringe driver is recommended as it provides the greatest flexibility in the palliative care setting
An infusion time of 24 hrs or longer for a 10 ml infusion volume; and,
Bolus dose capacity (limited)
The SIMS DELTEC CADD-PRIZM range of pumps utilise a reservoir cassette and are programmable for rates of background infusion, bolus dose frequency and size, and lockout period between bolus doses. In addition the pump can be programmed to allow the patient
or family to change some of the operating parameters.
|If the child has an implanted intravenous access device such as an Infusaport or *HICKMAN® catheter, to which the infusion device may be connected, it is recommended the infusion device have an air in line detector and alarms for various malfunctions such as pump stopped, low volume, rate too low/high,
low battery as a minimum requirement. |
|It is important that health professionals read the relevant instruction manual for all equipment used to deliver medications via the subcutaneous or intravenous route, and follow the advice and recommendations of the manufacturer. |
for using subcutaneous/intravenous infusions
Learning Modules for subcutaneous infusions in Palliative Care
- For placement of subcutaneous cannula
- Use local anaesthetic cream to avoid pain for the child when inserting the S/c cannula. Wait one hour to obtain maximum benefit.
- Use a small gauge intravenous (24/25G) plastic cannula in preference to a "butterfly" needle. This will improve patient comfort and may extend the life of the infusion site. This approach also allows variation in the type of tubing that may be used to
connect the various pieces of equipment together.
- Site the cannula in a place appropriate for the child's activity level, keeping in mind that as symptoms are relieved the child's level of activity may increase
- Use small bore tubing of a length that allows the child to manoeuvre the equipment to suit varying activities.
- Tubing and syringes should be Luer Lock type to avoid disconnection or leakage problems.
- If the infusion is an intravenous one an anti-syphon valve should be included in the system to prevent backflow of blood into the tubing at low flow rates
- Keep infusion volumes as small as practicable. This will not only reduce swelling at the site but may also extend the life of the infusion site.
- It is possible to administer more than one drug concurrently in the infusion but the advice of a pharmacist about drug compatibility should be sought prior to mixing drugs in infusions. The relative strengths of each drug may affect compatibilities Health professionals should also bear in mind that in mixed
solutions the giving of bolus doses of one drug will also provide a bolus of the second.
- Firmness and swelling at the injection site is not an indication for cannula change. Pain and obvious inflammation are indications for change.
- Manufacturers guidelines regarding the use of syringe drivers should be followed.
- Preparation of solutions should follow aseptic technique guidelines
- Water is the most common diluent but ketamine, ondansetron and some other drugs require sodium chloride 0.9%.
- Drugs should be diluted by at least 100%. Irritant drugs may require greater dilution.Solutions should be checked regularly for signs of incompatibility such as discoloration or precipitation.
- The operating parameters of the syringe driver should be checked regularly to ensure that it is working correctly.
- In oedematous children or those with poor circulation the use of an intravenous infusion in preference to a subcutaneous one is advised.
These drugs can usually be combined with morphine in an infusion, however health professionals are urged to consult with an experienced pharmacist in a major tertiary paediatric hospital if uncertain.
Hyoscine hydrobromide (Scopolamine)
http://www.pallcare.info provides an up-to-date database for syringe-driver drug compatibilities
|Incompatibility reactions occur between these drugs and morphine
Incompatibility reactions may occur between midazolam and morphine at high concentrations Careful observation is recommended.
|The following drugs are contra indicated for subcutaneous use as they are irritant to the skin.
1.Therapeutic Guidelines: Palliative Care. Therapeutic Guidelines. Melbourne. 2001.
* HICKMAN® is a
registered trade mark of C.R. Bard Inc.