In the olden days, it was a usual practice to pinch the skin at the injection site.
- This was done to avoid inserting the needle into the muscle tissue below the fat.
- If insulin is injected into the muscle, it hurts and results in a much faster insulin uptake, thus increasing the risk of hypoglycemia (low blood sugar).
- But this used to hold true because the older needles were longer (13 millimeters).
Today, most of the needles have lengths between 6 and 8 millimeters, and in most popular pens, needles of 4 millimeters are available.
Thus pinching has no benefit when we are using the currently available needles.
- The available lengths of pen needles are 4, 5, 6, and 8 mm with varying gauges.
- 4 or 5 mm pen needles as such can be used in adults at 90 degrees to the skin surface without a skin fold.
- For people with diabetes, the safest pen needle length is 4 mm.
- If you are going to use the 8 mm length pen needle, you have to inject it with a skin fold at a 45 degree, which can be quite inconvenient.
Lifted Skin Fold Technique
A skin fold method has to be used when injecting using a needle longer than 8 mm. the whole hand should not be used when lifting the skin and the folding method has to be slowly released following injection or else it could increase the possibility of intramuscular injection.
The proper way of lifting the skin is to use the thumb and two fingers with one hand as such can pull the skin and fat away from the muscles.
Keep the skin lifting while injecting insulin. In a lifted skin fold technique, the ideal needle length is less than 8 mm in children and very thin patients.
Please note : The lifted skin fold shouldn’t be squeezed so tightly that it causes blanching and pain
- 4 – 6 mm no need to pinch
- Pinch if less fat
- Perpendicular injection if adequate fat
Fact : During hot weather and exercise, the absorption of insulin is higher. Hence, the best insulin injection site in this situation is the buttocks
Note : Longer needle length increases the risk of intramuscular injection into the muscle fascia
Image : Green tick – Subcutaneous tissue (made of fat and connective tissues) is the preferred site for insulin injection as it offers it offers stable, slow and predictable absorption.