• Reservoir, cartridge and syringe
• Needle, cannula and catheter
• Tubing and line.
Choosing an infusion set that works well for you is very important to success with a pump. Most use what looks like a tiny IV line to pump (infuse) insulin from a reservoir. Patch pumps applied directly to the skin are now available in some places, but not in Canada.
The infusion set and site are often the weakest link in pumping. If the one you use irritates your skin, falls off when you swim or sweat or is easily dislodged, blood glucose control will suffer. To work properly, your infusion set must be reliable and comfortable.
Not all sets are the best design, nor are they guaranteed to work well for everyone. When selecting an infusion set, consider these questions.
The type of set shipped with a new pump is usually one manufactured for the pump company. It may or may not be the best choice for you. The pump may also come with sets recommended by your doctor or nurse educator. Samples of other sets may be in the pump box too. If possible, try different infusion sets before deciding which one is comfortable, easy to use, and stays in place. Fortunately, you can choose from many different sets.
Gauge is a standard way to measure the diameter of a needle or cannula. A higher gauge number means a needle has a smaller diameter. For example, a 28 gauge needle is smaller than a 25 gauge needle. Smaller diameter needles are usually more comfortable.
Today's straight-in metal sets offer fine gauge needles that are comfortable, reliable, and easier to insert. Teflon sets use a metal needle inserter. This device helps place the cannula and may simplify insertion. It is removed after insertion, leaving only the Teflon cannula under the skin. Inserters work better with straight-in sets than with slanted ones.
Generally, the longer the length of the Teflon cannula, the more reliable the set will be. Slanted Teflon sets tend to be more reliable for many pumpers than straight-in Teflon sets, but are generally best inserted by hand rather than with an automatic inserter.
Infusion sets come in different cannula lengths and different tubing lengths. Typical cannula lengths for straight-in sets are six millimetres for infants and children and eight to 10 mm for adults. For the slanted Teflon sets, 13 mm and 17 mm lengths serve similar functions.
The tubing connects the pump reservoir to the infusion set. Most infusion tubings are 24 inches (60 cm), 31 inches (90 cm), or 42 inches (110 cm) in length. Shorter tubing works better for small children and those who prefer it. Longer tubing works well for people who are taller. Tubing is sold with the infusion set and cannot be purchased separately.
Most infusion set tubing has a standard threaded Luer lock connection to connect with the reservoir. This allows you to choose from among about 20 different infusion sets that can be used on most pumps.
Not all pumps can be used with a Luer connector infusion set, but other options may be available. Discuss these with your insulin pump trainer.
All infusion sets must be anchored to the skin. Most have an integrated adhesive patch around the cannula. Before insertion, use an adhesive-containing ‘skin prep’ wipe. It cleans the skin and makes the area extra sticky, helping the patch stick to the skin better. This keeps tugs on the line from loosening the infusion set. A loose infusion set can leak small amounts of insulin, leading to high blood glucose levels.
If you answer yes to any of these questions, always be sure to anchor your infusion line with tape. Consider changing to a different set.
You must be able to rely on your infusion set, and most work well. However, some problems may not appear until a set is worn for some time, as with:
A trial run with various sets will likely pick up most of these problems. Since many options are available, don’t continue with a set that causes problems.
Several good books and websites are available to give you more information about infusion sets, insulin pumps and pumping insulin. Your diabetes care professional can advise you. Want to know about your choices and how to save money? Just ask your Safeway pharmacy staff for more information.