Pediatric ATI Practice Exam

Where should an intramuscular injection be administered to an 11-month-old infant?

1. Ventrogluteal site

2. Deltoid muscle

3. Rectus femoris

4. Vastus lateralis

The correct answer is: Vastus lateralis

When administering an intramuscular injection to an 11-month-old infant, the vastus lateralis muscle is the most appropriate site. This is because the vastus lateralis, located on the outer aspect of the thigh, is well developed in infants and offers a large muscle mass that can accommodate the volume of medication typically administered through intramuscular injections. Using the vastus lateralis site also minimizes the risk of injury to major nerves and blood vessels, which is particularly important in infants whose muscles are still developing and whose anatomical structures may be less defined than in older children or adults. In contrast, the ventrogluteal site is not recommended for infants due to the potential for not fully developed gluteal muscles and a higher risk of injury. The deltoid muscle is smaller and less developed in infants, making it an unsuitable choice for intramuscular injection as it may not hold enough medication safely. The rectus femoris muscle, while another possible site, is not preferred as it carries similar risks associated with the smaller muscle mass and potential for complications compared to the vastus lateralis. Thus, using the vastus lateralis ensures safety and effectiveness in delivering the necessary immunizations or medications for an infant at this developmental stage