Ultrasound-guided measurement of skin and subcutaneous tissue thickness in children with diabetes and recommendations for giving insulin injections

To measure skin thickness (ST) and skin + subcutaneous layer thickness (SCT) by ultrasound and estimate the risk of intramuscular injection (IM) with different needle lengths across injection sites according to age group. Children recruited between 1 and 18 years with type 1 and 2 diabetes on insulin injections and divided into three age groups: 1–6 years, 7–12 years and 13–18 years. A portable ultrasound was used to measure ST and SCT at four injection sites on the abdomen, arm, thigh and buttock. Total 153 children enrolled for the study. The mean (SD) measurement of ST & SCT at four sites on abdomen, arm, thigh & buttocks were as follows; 4.33 mm (±2.22), 5.55 mm (±2.26), 5.83 mm (±3.12), 6.48 mm (±3.47) in 1–6 years old; 7.11 mm (±3.68), 7.79 mm (±4.54), 7.17 mm (±3.62), 8.51 mm (±3.65) in 7–12 years old; 8.94 mm (±4.50), 8.42 mm (±5.00), 8.61 mm (±4.76), 9.76 mm (±4.38) in 13–18 years old. Young children, 1–6 years have the highest risk of IM injection with all needle lengths, i.e. 4, 5, 6, 8 & 12.7 mm, while older children 7–12 & 13–18 years have a lower risk with shorter needles (4, 5 and 6 mm) as compared to longer needles (8 and 12.7 mm). Children with diabetes on insulin therapy should be advised on the appropriate needle length accordingly to their age and BMI.