RESUMO
BACKGROUND: Insulin therapy is essential for type 1 diabetes. While a reasonable glycemic control prevents complications, inadvertent intramuscular (IM) insulin injection results in hypoglycemia and fluctuations of blood glucose levels. OBJECTIVE: To assess the subcutaneous thickness (SCt) at the potential insulin injection sites, in order to determine the suitable needle length. METHODS: Diabetic and non-diabetic children (n=125; aged 2-14 years) attending a tertiary care hospital were examined, after excluding those who had skin abnormality at the injection site, were hospitalized for>3 days, or had any other chronic illnesses. Dermal thickness (Dt) and SCt at the potential insulin injection sites were measured with ultrasonography. RESULTS: The mean age of the patients was 8 years and 57% were boys; mean Dt was 2.1±0.4 mm, SCt was 7.45.6±3.7 mm, and maximum SCt was 29.8 mm in the anterior abdominal wall. SCt increased with age and by raising a skin fold (sf). There was no difference (P>0.05) in Dt between genders, and limbs showed thinner Dt values than the abdomen. SCt changed with the injection site: it was the lowest in the thigh and the highest in the abdomen. SCt was thicker in females, with or without sf (P<0.001). For all sites, IM risk was high for 15-mm needles: it was highest in the thighs (98%) and reduced to 86% with sf. IM risk was low for 5-mm needles: it was highest in the thigh (38%), and reduced to 12% with sf. Compared with girls (up to 42%), IM risk was higher for boys (up to 54%), even for 5-mm needles with a sf. CONCLUSION: Using a short needle is recommended for children, particularly for boys. Regardless of the needle length, the raised sf technique is associated with reduced IM risk.