Muscle, subcutaneous tissue and total tissue thicknesses are important factors in successful intramuscular injection. Muscle mass decreases and subcutaneous tissue increases with age. This may negatively affect the safety and effectiveness of intramuscular injection in older adults by increasing the risk of bone contact and subcutaneous drug administration. Intramuscular injection sites should be evaluated in this respect, but no previous study has evaluated the most appropriate sites for safe and effective intramuscular injection in older adults.
This study aimed to examine the safety of dorsogluteal and ventrogluteal injection sites in older adults.
This cross-sectional study included 171 older adults who presented to the radiology clinic of a hospital between November 2022 and February 2023. We collected the study data using a descriptive characteristics form and an ultrasonographic measurement form. To complete the descriptive characteristics form, we interviewed the participants and measured their waist circumference, hip circumference, weight and height. Muscle, subcutaneous tissue and total tissue thicknesses at the ventrogluteal and dorsogluteal sites were determined by ultrasonography. This study followed the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guideline.
At the ventrogluteal and dorsogluteal sites, respectively, total tissue thicknesses were 59.43 ± 11.21 and 48.78 ± 9.68 mm, subcutaneous tissue thicknesses were 20.07 ± 6.64 and 22.97 ± 7.40 mm and muscle thicknesses were 40.13 ± 5.59 and 25.61 ± 4.30 mm. Tissue thicknesses at both sites differed according to sex, weight, hip circumference and waist circumference (p < 0.05). Although both sites were acceptable according to the tissue thickness thresholds for intramuscular injection given in the literature (subcutaneous tissue < 25 mm, total tissue > 35 mm), the ventrogluteal site was more advantageous in terms of greater muscle thickness and lower subcutaneous tissue thickness.
The results of this study indicated that both the ventrogluteal and dorsogluteal sites are safe for intramuscular injections in older adults in terms of tissue thickness. However, the ventrogluteal site may be safer for older adults because of the lower risk of bone contact and subcutaneous injection. Further studies are needed on this subject.
This study is important in terms of determining the safe and effective gluteal site for IM injection in older people aged 65 and over, preventing complications that may arise from site selection, and developing nursing policies that consider older people as a special group in the selection of IM injection sites.