Insulin injection technique

Introduction

Diabetes is one of the most common and serious chronic diseases. A third of its victims remain unaware that they have it. Each year, approximately 800,000 people are diagnosed with diabetes, its prevalence increasing steadily over the last half of this century. Incidence is expected to continue rising with the aging.

When talking about insulin injection techniques, followings should be considered.

1. Syringes
2. Insulin pen
3. other insulin aids
4. site selection
5. mixing of insulin
6. injection technique

SYRINGES

Insulin syringes are in the four basic capacities;
1. 1 cc (100 units)
2. 1/2 cc (50 units)
3. 3/10 cc (30 units)
4. 200-unit syringes (used in rare cases where patients require doses in excess of 100 units)
The unit scale or graduations on the barrel of the syringe may differ depending on the size of the syringe and the manufacturer;
1. 1 cc syringes usually marked in 2-unit intervals
2. 1/2 cc and 3/10 cc syringes in 1-unit intervals
The barrels of the smaller-capacity syringes are narrower to allow expansion of scales and easier reading, so patients should generally be counseled to use syringes with the smallest capacity that will accommodate the required dose.

Insulin syringes are also fitted with different needle gauges and lengths ranging from 28G, 29G and 30G. As with other needles, the higher the number of the needle gauge, the smaller the diameter of the needle. In general, patients prefer the thinner needles, associating thinner needles with greater comfort. Patients should be warned that with the thinner gauge needle also comes increased needle flexibility.

Insulin syringe needles are available in;
1. The standard 1/2-inch (12.7mm)
2. A shorter 5/16-inch (8 mm)
A patient changing needle lengths may experience a change in glycemic control, as absorption from a different subcutaneous depth can affect rate and extent of insulin absorption.
Insulin Pens

Insulin pens have become especially convenient for active people or those who have difficulty drawing insulin from a vial. They are compact, easy to carry and store, and discreet to use; and they eliminate the need to carry vials of insulin. Insulin is stored in a cartridge inside the pen, and the delivered dose is selected by turning a dial prior to activation of the device.
Other Injection Aids
Injecting insulin may become more difficult for patients with compromised dexterity or eyesight, so various injection aids have been designed to help overcome these difficulties. A magnifier fits around the syringe to enable the user with compromised visual acuity to read syringe measurements more accurately.
Automatic injector devices facilitate ease of administration, some delivering needle and insulin simultaneously and others requiring the user to push a syringe plunger after the needle has pierced the skin. Such a device may be helpful for people who have a fear of needles or of self-injection, as the injection is not directly observable.

Site Selection

Insulin is injected into the fatty tissue under the skin from which it is absorbed into the blood stream at rates that vary with the site of injection, so blood glucose values may also vary with injection site.

Common sites are;

1. Abdomen
2. Arms
3. Hip
4. Buttocks
5. Thigh

Absorption is most rapid from sites in the abdomen, somewhat slower from the arms, slower still from the legs, and slowest from the hip or buttock area.

Patients may choose one area over others because of comfort, or how quickly or slowly insulin is absorbed. Rotating injection sites within one area is generally recommended over rotating to a different area due to the variable absorption between the different sites. Increasing exercise of the injection site increases the rate of insulin absorption by enhancing blood flow to the area. Preferred sites for insulin injections include the upper arm, the anterior and lateral aspects of the thigh, the buttocks, and the abdomen (stomach area).

Mixing Insulins

Certain short-acting and long-acting insulins can be mixed in the same syringe to minimize the number of injections. The short-acting (clear) insulin should be drawn up first, followed by the long-acting insulin, as follows.

Hands should be cleaned with soap and water before mixixng
Mixing should be done gently by rolling the vial between the palms of the hands, or gently turning the bottle from end to end a few times. Do NOT shake!

Injection Technique

Detailed information regarding insulin injection technique should provided to the patient.

All the equipment should be ready. Then select the site.
Wash hands with warm, soapy water prior to the procedure.
After choosing an injection site, clean the area with an alcohol swab.
Pick up the syringe and uncap if previously recapped. “Pinch” the area of skin to be injected, and quickly push the needle through the skin at a 90° angle. Inject the insulin by pushing down on the plunger, release the pinched skin, and pull the needle straight out of the site. Press gently over the area injected with a finger or alcohol swab, but do not rub the area.
Dispose of used needles and syringes safely.


How do you minimize the pain?
1. Inject insulin at room temperature.
2. Remove all air bubbles from the syringe before injection.
3. Wait until topical alcohol has evaporated before injecting.
4. Keep muscles in the injection area relaxed during injection.
5. Penetrate the skin quickly.
6. Avoid changing direction of the needle during insertion or removal.
7. Do not reuse disposable needles.