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An angled insertion technique using 6-mm needles markedly reduces the risk of intramuscular injections in children
P L Hofman1, S A Lawton, J M Peart
1Liggins Institute, University of Auckland, Auckland, New Zealand. p.hofman@aucland.ac.nz
Insights
An angled 6-mm needle technique with a pinched skin-fold reliably delivers insulin into subcutaneous fat in children with Type 1 diabetes, reducing the risk of intramuscular injections.
Area of Science:
- Pediatrics
- Endocrinology
- Diabetes Management
Background:
- Intramuscular (IM) or intradermal (ID) insulin injections can affect glycemic control in children with Type 1 diabetes (T1D).
- Optimizing subcutaneous (SC) fat delivery is crucial for effective insulin therapy.
Purpose of the Study:
- To identify children with T1D at risk for improper insulin injection depths.
- To determine optimal needle length and injection technique for SC fat administration.
Main Methods:
- Two studies involving children with T1D (ages 6.3-14.3 years) were conducted.
- Ultrasound assessed air injection depth using various needle lengths (6-mm, 8-mm) and techniques (perpendicular, angled, pinched, unpinched).
- Subcutaneous fat thickness was measured under different skin-fold conditions.
Main Results:
- Standard injection protocols resulted in IM injections (32%) or near-muscle fascia air (22%).
- An angled 6-mm needle with a pinched skin-fold technique minimized IM injections (3%) and near-muscle fascia air (11%).
- Pinching increased SC fat thickness, though it reduced it in very lean subjects.
Conclusions:
- Frequent IM/ID injections occur with standard insulin injection protocols.
- An angled 6-mm needle and pinched skin-fold technique reliably ensure SC fat insulin delivery in pediatric T1D patients.
Aims:
The aims of this study were (i) to establish which children with Type 1 diabetes are at risk of intramuscular or intradermal insulin injections and (ii) to determine a needle length and technique that reliably administers insulin into subcutaneous fat.
Methods:
Seventy-two healthy diabetic children (age 6.3-14.3 years, body mass index standard deviation score 1.0 +/- 1.4) were recruited for study 1 and 37 of this cohort participated in study 2. In study 1, 200 microl air was injected into the abdomen and anterior thigh by a pinched skin-fold technique using either a perpendicular insertion of NovoFine(R) 31G 6-mm or an angled insertion of NovoFine(R) 30G 8-mm needles. In study 2, subjects received injections into abdomen and anterior thigh via angled 6-mm needles with either an unpinched or pinched technique. The site of air injection was visualized by ultrasound scan and measurements taken of subcutaneous fat thickness.
Results:
In study 1, intramuscular injections were detected in 32% of subjects, and in a further 22% air was visualized at the muscle fascia. In study 2, intramuscular injections occurred in 3% of subjects and a further 11% had muscle fascia air detected. No intramuscular injections occurred in subjects injecting with a 6-mm needle and an angled pinched skin-fold technique. Pinching abdomen and thigh skin folds increased the subcutaneous fat thickness by 192 +/- 16% and 22 +/- 6%, respectively. In very lean subjects, pinching thighs actually reduced subcutaneous fat thickness.
Conclusions:
While intramuscular injections were observed frequently using standard injection protocols, an angled 6-mm needle technique reliably injects into the subcutaneous fat.
